Assessment Summary Sheet for UKAB Meeting on 22 nd Jul 2015

Transcription

1 Assessment Summary Sheet for UKAB Meeting on 22 nd Jul 2015 Total Risk A Risk B Risk C Risk D Risk E Airprox Reporting (Type) Reported (Type) Airspace (Class) Cause ICAO Risk MD902 (NPAS) DA42 (Civ Comm) Manchester CTR (D) The DA42 pilot flew close enough to cause the MD902 pilot concern. C DHC8 (CAT) Drone (Unknown) London City CTR (D) The Drone was flown into conflict with the DHC8. Recommendation: The CAA liaise with NPCC to clarify Police response to ATC reports of Airprox involving drones. B Tornado (HQ Air Ops) C135 (Foreign Mil) London FIR (G) A conflict in Class G resolved by both pilots. C Apache (HQ JHC) Model Glider (Unknown) London FIR (G) A conflict in Class G resolved by the Apache pilot. B Dauphin (HQ JHC) Model Glider (Unknown) London FIR (G) A sighting report. E Lynx (RN) Drone (Unknown) London FIR (G) The Drone was flown into conflict with the Lynx. A AW139 (Civ Comm) Para-Motor (Unknown) London FIR (G) A late sighting by the AW139 pilot. Recommendation: The BHPA consider measures to educate paramotor pilots on best practice for crossing airfield approach lanes. C EMB170 (Civ Trg) PA28 (Civ Trg) Cambridge ATZ (G) The PA28 pilot flew into conflict with the EMB170. C PA28 (Civ Pte) Spitfire (Civ Pte) London FIR (G) The Spitfire pilot flew close enough to cause the PA28 pilot concern. C RJ85 (CAT) Met balloon (Unknown) London TMA (A) The RJ85 pilot was concerned by the proximity of the balloon. D PA28 (Civ Club) PA28 (Unknown) London FIR (G) A conflict in Class G resolved by the PA28 pilot. C Rotorway 162 (Civ Pte) Vans RV7 (Civ Pte) London FIR (G) A non-sighting by the RV7 pilot and effectively a non-sighting by the Rotorway pilot. A

2 Airprox Reporting (Type) Reported (Type) Airspace (Class) Cause ICAO Risk EC155 (Civ Comm) Typhoon FGR4 (HQ Air Ops) London FIR (G) The Typhoon pilot flew into conflict with the EC155. Contributory: 1. The Swanwick Mil controller passed Traffic Information relative to the Typhoon formation leader, not the No2. 2. The Typhoon pilots chose to operate adjacent to the HMR entrance/exit point. B PA28 (Civ Pte) Microlight (Unknown) London FIR (G) A late sighting by the PA28 pilot and a probable non-sighting by the microlight pilot. A LS4 Glider (Civ Pte) F4U Corsair (Civ Comm) London FIR (G) A conflict in Class G. Contributory: The Corsair pilot chose to conduct his shakedown flight in a promulgated area of intense gliding activity. B Tornado GR4 (HQ Air Ops) F15 x 2 (Foreign Mil) London FIR (G) The Tornado pilot chose to depart under VFR in broken cloud and flew into conflict with the F15s. Contributory 1. An incorrect initial frequency selection by the Marham controller. 2. A nonstandard and overly complex RT call to the Tornado crew. 3. The Tornado crew did not assimilate their TCAS information. 4. The agreed Lakenheath/Marham coordination was ineffective and unachievable. Recommendation: Marham and Lakenheath review their coordination procedures with regard to simultaneous aircraft recovery and departure. C Cirrus 75B (Civ Pte) Light aircraft (Unknown) London FIR (G) A late sighting by the Cirrus pilot and probably a non-sighting by the light aircraft pilot. A x 2 Tucano (HQ Air Trg) Tucano (HQ Air Trg) North Yorkshire AIAA (G) Linton ATC did not sufficiently synchronize Tucano (B) and the Tucano formation. C PC12 (Civ Comm) C152 (Civ Club) London FIR (G) The PC12 pilot flew into conflict with the C152. A

3 Airprox AIRPROX REPORT No Date: 10 Apr 2015 Time: 0029Z (Night) Position: 5331N 00202W Location: IVO Oldham PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft MD902 DA42 Operator NPAS Civ Comm Airspace Manchester Manchester Class D D Rules VFR VFR Service Radar Control Radar Control Provider Manchester Manchester Altitude/FL FL 012 FL017 Transponder A,C,S A,C,S Reported Colours Black/Yellow White/Yellow Lighting Strobes/Nav lights. Nav, anticolls,landing Conditions VMC VMC Visibility 8km 10km Altitude/FL 1950ft 1749ft Altimeter QNH (1021hPa) QNH (1021hPa) Heading Speed 40kt 140kt ACAS/TAS TCAS I Other TAS Alert TA TA Separation Reported 0ft V/600m H 300ftV/200m H Recorded 500ft V/0.2nm H THE MD902 PILOT reports that he was tasked from Reddish in central Manchester, to an area SE of Oldham, a request was made to transit at 2000ft. ATC granted an upper limit of 2500ft, but he elected to stay at 2000ft. At Stalybridge he decreased speed and took up a northerly track to start working in the area. He recalls that at this time ATC passed Traffic Information to the flight calibrator about his flight. This was followed by an acknowledgment of visual by the calibrator pilot. The aircraft was in the helicopter s rear quadrant so he was unable to visually identify it, and had to rely on his TCAS for information. A TCAS warning identified an aircraft in the 4 o clock position at the same height and less than a mile away. He knew the aircraft was carrying out a calibration so he realised it had started its ILS approach and so he increased speed on a northerly heading to increase separation. He heard the calibration pilot state that he was going to abort his approach and reposition. At this point the helicopter was at the most northerly point of the search so the pilot slowly banked left to confirm the position of the other aircraft. The two policemen on the left of the helicopter saw the other aircraft first, and then the pilot spotted it in a steep right-hand bank, then level on an intercepting course. He saw the landing-light come on and immediately illuminated his own. He saw no apparent change in course so when the other aircraft was 600m away, he took avoiding action by descending steeply. The task was then cancelled and they returned to base. He assessed the risk of collision as High. THE DA42 PILOT reports that he was calibrating the RW23R ILS at Manchester airport, with a VFR clearance to operate autonomously within the CTR, not above 3000ft. They had been on task for over an hour and were positioning for a profile that required the aircraft to be established on the ILS at 12nms at a height of 1500ft, which was lower than an aircraft would ordinarily be at this range from the runway. He was aware of a Police Helicopter that had been operating in the area for the past 1

4 Airprox mins, but it had been on task to the north of the extended centreline and their positioning legs had all been to the south. Throughout, Manchester had given regular Traffic Information to both pilots and he had predominantly kept visual contact with the helicopter, backed up by TAS information. Just prior to the Airprox the helicopter changed position to one estimated to be just south of the extended centreline at a range of 15nm, at an altitude slightly below that of the DA42. He maintained visual contact throughout this change in operating area. He then commenced the flight profile, turning in at 12nm, however, due to an on-board equipment issue, he had to terminate the calibration run at 10.5nm and, aware that the helicopter was in their rear left quadrant, he turned right to the north of the centreline in order to re-position and repeat the profile from 12nm. Once downwind he observed the helicopter in his 2 o clock, it appeared to be engaged in an orbit just the other side of a ridgeline. At 12.6nm he initiated a relatively tight right turn to establish back on the extended centreline and momentarily lost visual contact with the helicopter as it became obscured by the aircraft s nose, but regained contact in his low 11 o clock. At this point Traffic Information was given by the Manchester Controller, and on completion of this transmission the helicopter pilot announced he was descending and it was immediately apparent that he was concerned by the proximity of the calibrating aircraft. The DA42 pilot commenced a climb whilst continuing the turn and the TAS gave a single Traffic Alert. He subsequently lost contact with the helicopter as it passed under his left wing whilst they were in the climb. He assessed the risk of collision as None. THE MANCHESTER CONTROLLER reports that he submitted the report after the event because initially the pilot of the MD902 had indicated he wasn t going to report the incident as an Airprox. The MD902 pilot had requested to operate in the Oldham area, but was actually operating 5nm south in the Stalybridge area. At the same time the DA42 was carrying out calibration work on the 23R ILS and was 1nm south of the approach beam at a range of 9nm. The controller passed Traffic Information to both pilots and the DA42 commenced a run tracking North West bound. The controller checked the intentions of the MD902 pilot because he was operating in a different location and he stated he was moving northeast. Further Traffic Information was passed to the MD902 pilot and he reported visual. The DA42 pilot then stated that he would have to break off his run and reposition; because the police helicopter had stated he was moving further northeast, the controller was happy to let the flight calibrator re-position without any restrictions. The MD902 then became stationary and began to drift slightly westbound, putting both aircraft on converging tracks. The controller asked the DA42 pilot to confirm he was still visual with the helicopter, now 12 o clock, 1nm, to which he replied he was. The MD902 pilot then sounded slightly panicked and stated he was descending. Factual Background The weather at Manchester was reported as: METAR EGCC Z 17005KT 8000 NSC 10/06 Q1021 NOSIG Analysis and Investigation CAA ATSI The DA42 (code 0024) was conducting flight calibration checks and the MD902 (code 0041) was operating to the north of the DA42. Both aircraft had been operating under a Radar Control Service, provided by Manchester Approach Radar, in Class D airspace, for approximately 40 minutes prior to the Airprox. During this time, regular traffic information had been passed to each aircraft on the other. At 0026:00 the DA42 reported positioning for a profile 16 and the Manchester Approach controller passed Traffic Information on the MD902 in the DA42 s twelve o clock at 2nm which was acknowledged. The MD902 pilot reported routeing further off towards the northeast and was passed Traffic Information on the DA42. He reported having the DA42 on TCAS at 0026:30. The Manchester Approach controller then asked the DA42 pilot if they were visual with the MD902 to which he replied Affirm. At 0028:14 (Figure 1), the DA42 pilot reported running in which was acknowledged by Manchester Approach. The Manchester controller stated 2

5 Airprox that, because the MD902 had reported moving north east, he was happy to let the DA42 reposition without any restriction or direction of turn. The controller, having been providing timely and continuous Traffic Information for approximately 40 minutes - as required when providing a Radar Control Service was likely to have been satisfied that the pilots were fully aware of the position of the other aircraft. The radar recording showed that the DA42 continued in a right hand turn back towards Manchester and flew over the MD902. CPA occurred between the two consecutive radar pictures (Figure 2 and Figure 3) with a vertical distance of between 400ft and 900ft. The MD902 pilot reported descending to avoid the DA42. It was observed that the DA42 initiated a climb to an indicated 2200ft (700ft above the selected 1500ft as depicted via the Radar Mode S). The DA42 descended to an indicated 1700ft within the next minute. The unit could add no additional information. Figure 1 (0028:14) Figure 2 (0029:06) Figure 3 (0029:12) UKAB Secretariat Both pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard. 1 1 SERA.3205 Proximity. 3

6 Airprox Comments NPAS As with many aerial applications a balance has to be struck between being effective, achieving the task safely, and disruption to other airspace users. Increased interaction with other users, such as in this scenario, has the effect of eroding the pilot s spare capacity and risks compromising the other two outcomes. In Police operations, the aircraft commander may, depending on the significance of the task, have the option of applying an Alpha suffix to their callsign to take priority over other traffic but this was clearly not warranted in this case. Both aircraft were therefore operating legitimately and on an equal priority basis in accordance with their default Bravo suffix conditions of their Special Flight Notifications - the Police pilot elected to redress the balance by leaving the scene. Summary An Airprox was reported on 10 th April 2015 at 0029 between a MD902 and DA42. Both were receiving a Radar Control Service from Manchester ATC, and were in Class D airspace. The DA42 was flight calibrating the ILS and the MD902 was on a police tasking in the Oldham area. Apart from momentarily losing contact during his turn, the DA42 pilot was visual with the MD902 throughout, Manchester ATC gave Traffic Information to both pilots, and both pilots received Traffic Information from their TCAS/TAS. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the pilots of both aircraft, transcripts of the relevant RT frequencies, radar photographs/video recordings, reports from the air traffic controllers involved and reports from the appropriate ATC and operating authorities. The Board first considered the actions of the MD902 pilot. They noted that he was on-task, and probably focussed on the job in hand. He was aware of the DA42 through Traffic Information, TCAS information, and could hear the RT calls, but the Board thought it likely that he had not expected it to be as low as it was in that area. Some members wondered whether he may also have experienced startle-factor as his crew reported seeing the other aircraft before he could, and then suddenly seeing the other aircraft. Coupled with the fact that, at night, depth perception is difficult to judge, members wondered whether it may be that he also thought the other aircraft was closer than it actually was. Turning to the DA42 pilot, the Board were informed by a member who had previously been a flight checker that the low positioning of the DA42 was normal for Manchester runs, and that dispensation would have been given to allow the aircraft to operate closer to high ground than normal. That said, it was stressed that the pilot would have been mindful that although undertaking runs on the set profile was safe, turning away from the profile had inherent risks. Therefore, the Board were informed that he would likely have been keen to manoeuvre as close to the profile as possible, and this would account for his tight right turn. Some Board members wondered whether he would have been better served taking a left turn, away from the high ground and the helicopter. However, taking into consideration his need to remain as close as possible to his calibration profile, they reasoned that his decision to turn right was understandable. Notwithstanding, they did note that this probably meant that, already being task-focused, he had put himself under further pressure by turning towards high ground and the helicopter at night, when it may have been better to have discarded the run altogether and reposition again. The Board also commented that, although being visual with the helicopter himself, he may not have appreciated that his manoeuvring might startle the other pilot given the added factor of operating at night and the potential therefore that the MD902 pilot might not have been visual with him. 4

7 Airprox The Board noted that both pilots were undertaking unusual tasks, both requiring a degree of priority, and that both pilots may have been under pressure to achieve their particular aims. The Board agreed that the controller had done his best to provide Traffic Information to the pilots, both of which were operating VFR and therefore did not need to be formally separated by the controller. The Board further noted that this Traffic Information had cued the DA42 pilot to see the MD902 at an early stage, and the MD902 pilot to see the DA42 as they turned into conflict with each other. The Board further noted that both pilots had gained Traffic Information from TCAS. Considering the geometry of the encounter, when looking at the cause of the Airprox the Board agreed that it had been the DA42 pilot who had flown close enough to cause the MD902 pilot concern. But in assessing the risk, they decided that, because the DA42 pilot was visual with the MD902, there had been no risk of collision; timely and effective actions had been taken, and so they therefore assessed it as Category C. PART C: ASSESSMENT OF CAUSE AND RISK Cause: The DA42 pilot flew close enough to cause the MD902 pilot concern. Degree of Risk: C. 5

8 AIRPROX REPORT No Date: 19 Apr 2015 Time: 1315Z Position: 5130N 00003E Location: SW London City (Sunday) PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft DHC8 Drone Operator CAT Unknown Airspace City CTR City CTR Class D D Rules IFR NK Service Radar Control NK Provider Thames NK Altitude/FL 2000ft NK Transponder On, A, C, S NK Reported Colours NK Black/white Lighting NK None Conditions NK NK Visibility NK NK Altitude/FL 2000ft 2000ft Altimeter NK NK Heading 090 NK Speed NK NK ACAS/TAS TCAS II NK Alert Nil NK Separation Reported 0 V/50-150m H NK Recorded NK THE DHC8 PILOT reports flying downwind to RW09 at London City, level at 2000ft when a black and white object passed down the right-hand side of the aircraft at the same level. The object may have been stationary. He described the object as a drone with lettering on it, both pilots agreed that one of which was an X. On disembarkation, a passenger also reported sighting the object. He perceived the severity of the incident as possibly catastrophic. Factual Background The weather at London City at the time of the incident was: METAR EGLC Z 01008KT 340V SCT033 BKN042 10/02 Q1023 Analysis and Investigation CAA ATSI The DHC8 was being vectored for an ILS approach to Runway 09 at London City. When the aircraft was approximately 3 miles south of London City Airport, and downwind right-hand for runway 09, the pilot reported seeing a drone at approximately 200m range and at the same height of 2000ft. The pilot reported the incident to ATC at the time. After landing the pilot and co-pilot, who had also seen the object, agreed that the miss distance was likely to be m and that the object was at least 1 metre in size, was black and white in colour and had some letters on it (the second of which may have been an X). A query to London City Tower after landing confirmed

9 Airprox that they had had a similar report but not on that day. A passenger on the aircraft also reported seeing a black and white object. A review of the radar did not show any contact in the vicinity. UKAB Secretariat The Air Navigation Order 2009 (as amended), Article states: A person must not recklessly or negligently cause or permit an aircraft to endanger any person or property. Article 166, paragraphs 2, 3 and 4 state: (2) The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made. (3) The person in charge of a small unmanned aircraft must maintain direct, unaided visual contact with the aircraft sufficient to monitor its flight path in relation to other aircraft, persons, vehicles, vessels and structures for the purpose of avoiding collisions. (4) The person in charge of a small unmanned aircraft which has a mass of more than 7kg excluding its fuel but including any articles or equipment installed in or attached to the aircraft at the commencement of its flight must not fly the aircraft (a) in Class A, C, D or E airspace unless the permission of the appropriate air traffic control unit has been obtained; (b) within an aerodrome traffic zone ; or (c) at a height of more than 400 feet above the surface unless it is flying in airspace described in sub-paragraph (a) or (b) and in accordance with the requirements for that airspace. A CAA web site 2 provides information and guidance associated with the operation of Unmanned Aircraft Systems (UASs) and Unmanned Aerial Vehicles (UAVs). The CAA has published a UAV Safety Notice 3 unmanned aircraft. This includes: which states the responsibilities for flying You are responsible for avoiding collisions with other people or objects - including aircraft. Do not fly your unmanned aircraft in any way that could endanger people or property. It is illegal to fly your unmanned aircraft over a congested area (streets, towns and cities). Also, stay well clear of airports and airfields. In addition, the CAA has published guidance regarding First Person View (FPV) drone operations which limit this activity to drones of less than 3.5kg take-off mass, and to not more than 1000ft 4. Summary An Airprox was reported on Sunday 19 th April 2015 at 1315 between a DHC8 and an unknown object, described as a drone. The DHC8 was downwind right-hand to land at London City. No other radar returns were seen in the vicinity of the aircraft. There are numerous parks and open spaces where drones could be operated from that were close to the flight path at the time the incident was reported. 1 Article 253 of the ANO details which Articles apply to small unmanned aircraft. Article 255 defines small unmanned aircraft. The ANO is available to view at CAP ORSA No Small Unmanned Aircraft First Person View (FPV) Flying available at: 2

10 Airprox PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the pilots, radar photographs/video recordings, reports from the air traffic controllers involved and reports from the appropriate ATC and operating authorities. The Board noted, as it had done for many other recent Airprox involving drones, that the drone should not have been at 2000ft altitude anyway, let alone in the vicinity of London City Airport. Noting that on 8 May 2015 the CAA had issued CAP 493 SI 2015/02 (Issue 1), AIRPROX Involving Small Unmanned Aircraft, 5 which refers to the reporting of drone Airprox incidents to the civil police as soon as practical to initiate tracing action, the Board questioned if there were any particular Police procedures when receiving reports of drone activity near aerodromes, as is the case with laser attacks. Anecdotal evidence indicated that when some incidents had been recently reported the receiving police force had either not responded or had not known what to do with the information. The Board felt that it would be useful for the CAA to enter into a dialogue with the National Police Chiefs Council (NPCC) regarding the continuing problem of drones and, in particular: how to enforce the regulations; what specific actions the police would take on receiving a drone report and the setting up of a database of drone incidents that could be used to assist in future investigations. Whilst the Board was aware that the CAA were in the process of highlighting the issue and associated regulations for operating drones, it remained clear that there was a general inability to enforce them. The Board s discussion on the issue of drone Airprox ranged far-and-wide. Options such as Geo- Fencing (which could restrict drones and other UAVs from operating in sensitive airspace such as aerodromes); drone registration (whereby every drone could be registered to a specific user); drone activation codes (whereby drone purchasers would have to access the CAA drone website for an activation code prior to first use of the drone and thereby have the opportunity to read associated advisory material) were all discussed as potential ways to help address the problem of illegal drone use. Members pointed out that many of these solutions would probably not be a difficult barrier to those with the technical ability to overcome, but at least they might help educate and stop those who were consumer-operators who might know no better. In conclusion, the Board agreed that the cause of the Airprox had been that the drone had been flown into conflict with the DHC8. Although there was no radar information to measure the separation, it was clear that the pilots of the DHC8 had seen the drone at close-quarters (at m, and able to read the writing on the drone), and so the Board assessed that safety margins had been much reduced below the norm; they categorised the incident as risk Category B. PART C: ASSESSMENT OF CAUSE AND RISK Cause: The drone was flown into conflict with the DHC8. Degree of Risk: B. Recommendation: The CAA liaises with NPCC to clarify Police response to ATC reports of Airprox involving drones. 5 Which is an amendment to the Airprox reporting procedure at Section 6, Chapter 3 of CAP 493 (Manual of Air Traffic Services Part 1) and states that reporting action at aerodromes and ACCs is to include notification to civil police of the location of the Airprox as soon as practicable to initiate tracing action. Available at 3

11 AIRPROX REPORT No Date: 20 Apr 2015 Time: 0946Z Position: 5310N 00017W Location: 2nm NW Skegness PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft Tornado C135 Operator HQ Air (Ops) Foreign Mil Airspace London FIR London FIR Class G G Rules VFR IFR Service Traffic Traffic Provider Swanwick Mil Swanwick Mil Altitude/FL FL140 FL154 Transponder A, C, S A, C, S Reported Colours Grey NK Lighting Nav, HISLs NK Conditions VMC VMC Visibility 50km NK Altitude/FL FL150 FL140 Heading Speed 300kt 275kt ACAS/TAS TCAS II (TA only) TCAS II Alert TA RA Separation Reported 1000ft V/<0.5nm H 0ft V/ 0.5nm H Recorded 1400ft V/1.2nm H THE TORNADO PILOT reports leading a flight of 2 GR4s, climbing out of Marham. The lead aircraft was equipped with TCAS and was flying with it selected to TA only at the time of the incident 1. Both aircraft were co-level and within 0.3nm. As the formation was climbing through FL142, Swanwick Mil advised that they were approaching controlled airspace and asked if both aircraft were co-level and within one mile to which the lead replied "Affirm". Just after this, as the aircraft were passing FL145, TCAS gave a Traffic Alert and, immediately after this, Swanwick Mil called, "Traffic, left, 10 o'clock, range 10 miles, crossing left-to-right, slightly ahead, indicating FL150". The rear-seat crewman of the lead Tornado focused on TCAS at this point and gave relative height calls from TCAS to the pilot whilst the pilot attempted to gain visual contact with the traffic. The formation number 2 called visual with the traffic, and initially assessed it as heading in the same direction as the formation. The lead pilot then gained visual contact and re-assessed it as being co-level with the formation at FL150 and on a collision course. An immediate descent was initiated to FL140 and the traffic was seen to pass less than 0.5nm behind the formation and 1000ft above. He assessed the risk of collision as Medium. THE C135 PILOT reports on ATC vectors under a Deconfliction Service, climbing through FL140 to FL150 when a pair of Tornados flew across their nose from right to left. The crew was first alerted by a TCAS RA Descend, immediately visually acquired the Tornados, which were descending through their altitude, and elected to continue climbing. The TCAS RA Descend then switched to an RA Climb. He assessed the risk of collision as Medium. 1 In accordance with Standard Operating Procedures at the time. 1

12 Airprox THE SWANWICK MIL CONTROLLER reports his narrative was filed a few days after the event as the Airprox was not notified on frequency at the time or immediately after landing. He was the East Tac Left controller during a busy phase with a Planner and Tac Right controller in place. There was a busy radar picture in the background to his traffic, with some of his formations under a reduced service due to high traffic density. He recalled he had 9 speaking units on frequency at the time: 3 x F15s conducting general handling under separate squawks near Cottesmore; 2 x F15s conducting general handling in the Norwich area; 2 x F15s which had just free-called north of D207 for radar pick up for individual service and were identified just before the Airprox Tornado formation called; a C510 out of Norwich for CAS join under a Deconfliction Service; and a C340 transiting across the Norfolk coast, southeast bound for CAS join. The Tornado formation had been prenoted from Marham, climbing to FL190, and the controller called a conflictor to them that was west of their position by about 10 miles, indicating FL150. He recalled thinking that their rate of climb would take them above this level before it would become a factor. Shortly afterwards the crew informed him they were visual and were electing to descend to FL140 to go beneath it, a decision taken and communicated to the controller before the traffic had got within 3 miles. The controller did not believe there was anything else to note prior to sector transfer. He perceived the severity of the incident as Low. THE SWANWICK MIL OVERLOAD 2 CONTROLLER was not made aware that an Airprox had been filed and did not file a report. THE SUPERVISOR reports that the incident occurred nearly 1 month prior to the request to complete a report and that he had no recollection of the events. Factual Background The weather at Coningsby was recorded as follows: METAR EGXC Z 07007KT 9999 FEW025 BKN250 11/04 Q1031 BLU NOSIG A transcript of the Swanwick Mil Tac Left RTF was provided as follows: From To Speech Transcription Time Tornado S wick TL Swanwick Mil [Tornado C/S] flight on handover 09:43:17 S wick TL Tornado [Tornado C/S] flight Swanwick Mil identified climbing flight level one 09:43:20 nine zero, Traffic Service Tornado S wick TL Traffic Service in the climb flight level one nine zero for [Tornado 09:43:26 C/S] S wick TL C510 [C510 C/S] Radar Control climb flight level two six zero 09:43:30 C510 S wick TL Radar Control climb flight level two six zero [C510 C/S] 09:43:33 S wick TL C510 [C510 C/S] squawk five four one four 09:43:46 C510 S wick TL five four one four [C510 C/S] 09:43:49 S wick TL F15 [F15 C/S] confirm you intend to work with [Other F15 C/S]? 09:44:01 F15 S wick TL [F15 C/S] ah, in approximately two zero mikes we ll be working [Other F15 C/S] S wick TL F15 [F15 C/S] roger reduced Traffic Information from all around whilst you work western edge of East Anglia er, due to high traffic density F15 S wick TL [F15 C/S] copies we ll be working in our present position request flight level five zero, two four zero S wick TL F15 [F15 C/S] flight manoeuvre as required flight level five zero, flight level two hundred, and I m just working on that separate squawk for your wingman F15 S wick TL [F15 C/S] copies all working five zero to flight level two hundred, standing by for separate squawk for [F15 No2 C/S] 09:44:05 09:44:09 09:44:18 09:44:24 09:44:31 2

13 Airprox From To Speech Transcription Time S wick TL Tornado [Tornado C/S] flight as you approach controlled airspace confirm 09:44:43 both aircraft are within one nautical mile at the same level in the climb? Tornado S wick TL Affirm [Tornado C/S] 09:44:50 S wick TL Tornado [Tornado C/S] traffic left 10 o clock, one zero miles, crossing left to 09:44:52 right er, slightly ahead indicating flight level one five zero?? [Short burst of static] 09:45:02 S wick TL C510 [C510 C/S] continue with Scottish one three three decimal eight 09:45:04 C510 S wick TL One three three decimal eight [C510 C/S] 09:45:08 S wick TL F15 [F15 C/S] squawk six zero six seven 09:45:10 F15 S wick TL six zero six seven [F15 C/S] 09:45:12?? TCAS contact 09:45:17 Tornado S wick TL [Tornado C/S] we re descending flight level one four zero, we are 09:45:19 visual with that traffic?? flight level one five zero S wick TL Tornado [Tornado C/S] acknowledged 09:45:25 F15 S wick TL Swanwick confirm you d like [F15 No2 C/S] to squawk six zero six 09:45:31 seven? S wick TL F15 No2 [F15 No2 C/S] affirm squawk six zero six seven, [F15 C/S] maintain 09:45:35 your squawk of six zero seven five F15 S wick TL [F15 C/S], [F15 No2 C/S] copies. 09:45:41 S wick TL F15 No2 [F15 No2 C/S] identified er, confirm squawking with charlie? 09:46:14 F15 No2 S wick TL [F15 No2 C/S] affirm 09:46:20 S wick TL F15 No2 [F15 No2 C/S] squawk charlie 09:46:33 F15 No2 S wick TL [F15 No2 C/S] recycling 09:46:37 S wick TL F15 No2 [F15 No2 C/S] er identified Traffic Service, verify level 09:46:39 F15 No2 S wick TL [F15 No2 C/S] traffic, level one five zero 09:46:44 Other F15 S wick TL Swanwick say again for [Other F15 C/S] 09:46:47 S wick TL Other F15 [Other F15 C/S] flight that call is not for you 09:46:51 Other F15 S wick TL Copied thanks 09:46:54 S wick TL Tornado [Tornado C/S] flight Radar Control as you enter controlled airspace. 09:46:57 Tornado S wick TL [Tornado C/S] approaching level one nine zero request further climb 09:47:05 to two three zero S wick TL Tornado [Tornado C/S] flight climb flight level two three zero 09:47:14 Tornado S wick TL Flight level two three zero for [Tornado C/S] flight 09:47:17 S wick TL Tornado [Tornado C/S] flight squawk six zero five one 09:47:20 Tornado S wick TL Six zero five one for [Tornado C/S] flight 09:47:23 S wick TL Tornado [Tornado C/S] Traffic Service as you leave controlled airspace 09:47:51 Tornado S wick TL Traffic Service [Tornado C/S] flight 09:47:55 S wick TL Tornado [Tornado C/S] flight contact Swanwick Mil two seven five decimal 09:48:28 five zero Tornado S wick TL two seven five decimal five zero [Tornado C/S] flight push 09:48:34 A transcript of the Swanwick Mil Overload 2 console RTF was provided as follows: From To Speech Transcription Time C135 S wick O2 Control [C135 C/S] with you level one five zero 09:37:57 S wick O2 C135 [C135 C/S] Swanwick Mil identified flight level one five zero, Traffic 09:38:02 Service, confirm your intentions C135 S wick O2 Er, one five zero for [C135 C/S] we re level and er, continue flight 09:38:11 planned route for [C135 C/S] S wick O2 C135 [C135 C/S] roger confirm you re joining at ENITO 09:38:18 C135 S wick O2 [C135 C/S] is er direct er Charlie Golf er Yankee at the moment 09:38:24 3

14 Airprox From To Speech Transcription Time S wick O2 C135 [C135 C/S] roger Holbeach Range is active remain outside 09:38:32 C135 S wick O2 Er [C135 C/S] er confirm er???? remain outside 09:38:37 S wick O2 C135 [C135 C/S] er Delta two zero seven currently erm north of you by 09:38:42 three miles C135 S wick O2 [C135 C/S] er 09:38:50 S wick O2 C135 [C135 C/S] suggest turn left heading two seven zero degrees 09:38:54 C135 S wick O2 Two seven zero [C135 C/S] 09:38:57 C135 S wick O2 [C135 C/S] is er clear of the airspace request direct er charlie golf 09:39:56 yankee when able S wick O2 C135 [C135 C/S] roger own navigation to charlie golf yankee 09:40:01 C135 S wick O2 Resuming navigation charlie golf yankee [C135 C/S] 09:40:05 S wick O2 C135 [C135 C/S] what level do you require for your cruise? 09:44:00 C135 S wick O2 Er [C135 C/S] would like to remain at one five zero until we are A R 09:44:06 complete S wick O2 C135 [C135 C/S] er roger confirm you are routing to ENITO this time 09:44:13 C135 S wick O2 Er say again for [C135 C/S] we ll be er refuelling with er tanker 09:44:21 S wick O2 C135 [C135 C/S] roger that s copied erm are you going to the tanker now 09:44:27 C135 S wick O2 Er Affirmative [C135 C/S] it s er???? 09:44:32 S wick O2 C135 [C135 C/S] roger, traffic right one o clock eight miles, crossing right 09:44.38 left, it s two Tornados, flight level one four zero, climbing C135 S wick O2 [C135 C/S] copies, searching 09:44.47 C135 S wick O2????? control we re manoeuvring to avoid some Tornados 09:45.33 S wick O2 C135 [C135 C/S] confirm you er staying level one five zero? 09:45.43 C135 S wick O2 Errr [C135 C/S] had to climb, that s for an RA alert for some 09:45.48 Tornados S wick O2 C135 [C135 C/S] roger that s copied 09:45.55 C135 S wick O2??? returning to??? 09:45.58 Analysis and Investigation Military ATM The incident occurred on 20 Apr 15 at 0945, north of the Wash. The Airprox occurred between a Tornado GR4 and a USAF C135, both under a Traffic Service with Swanwick (Mil) but with different controllers. The radar replay was based on the London QNH 1028 hpa. At 0943:20, Swanwick Tac Left controller confirmed, [Tornado C/S] flight Swanwick Mil identified climbing FL190 Traffic Service. At 0944:38, Swanwick Overload 2 controller transmitted, [C135 C/S] roger. Traffic right, 1 o clock, 8 miles crossing right left. It s two Tornados. Flight level climbing. The aircrew replied that they were searching. At 09:44:38, Swanwick Overload 2 called traffic to the C135 pilot as, [C135 C/S] traffic right 1 o clock eight miles, crossing right to left, it s 2 Tornados, FL140, climbing. This call was acknowledged at 09:44:47, [C135 C/S] copies, searching. At 09:44:52 (Figure 1), Swanwick Tac Left called traffic to the Tornado formation as, [Tornado C/S] traffic left 10 o clock one zero miles crossing left to right er, slightly ahead indicating FL150. 4

15 Airprox Figure 1: Traffic Information at 0944:52 (Tornado 6065; C ) At 09:45:19 (Figure 2), the Tornado lead confirmed, [Tornado C/S] we re descending FL140 we are visual with that traffic at FL150. Figure 2: Tornado descending at 0945:18 At 0945:33, the C135 pilot commented, control we re manoeuvring to avoid some Tornados. The CPA was at 0945:38 with 1400ft vertical and 1.2nm horizontal separation. Swanwick Overload 2 asked if they were staying at FL150 and the C135 pilot replied at 0945:48 with, Errr [C135 C/S] had to climb. That s for an RA alert for some Tornados. As per the provision of a Traffic Service (CAP774), the Swanwick Tac Left controller provided Traffic Information at 10nm and the Swanwick Overload 2 controller at 8nm. From the RT, Tac Left was busy and was constantly passing traffic and control instructions to the aircraft under a service. Due to a delay in reporting the Airprox to the Overload 2 controller, limited information was available; RAF(U) Swanwick confirmed that controller was on the overload console and that the East console had a planner, 2 Tacs and the Overload controller. It is assumed that the Overload controller and the unit had a high workload at the time of the incident. The Tornado lead element used a combination of Traffic Information, TCAS information and a visual sighting by the wingman to visually acquire the C135. The crews were trained and briefed on TCAS but had limited live experience of the equipment. The C135 crew had received accurate Traffic Information and had also received a TCAS RA to descend; however, the crew had visually acquired the descending Tornados and decided to climb. Subsequently, the TCAS RA changed to a climb instruction. The C135 pilot had reported being under a Deconfliction Service but the transcript confirmed that the controller had applied a Traffic Service. 5

16 Airprox In this instance, numerous barriers worked to help paint a picture for the Tornado crew and they confirmed descending at 3.5nm horizontal separation with a CPA of 1.2nm and 1400ft. The type of service was appropriate and provided guidance at 10nm. The controller of the C135 had provided information at 8nm and had added details on the conflicting traffic. The Tornado crew used TCAS to get height information on the other track, and the post-incident investigation made further recommendations on TCAS operation for the Tornado Force. Eventually, lookout also worked as a barrier and enabled the crews to see and avoid. UKAB Secretariat The Tornado and C135 pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 2. The incident geometry was converging and the C135 pilot was required to give way to the Tornado formation 3. Occurrence Investigation The Tornado Unit Occurrence Investigation identified that a combination of Air Traffic Control, lookout and Collision Warning System [alert] ensured that flight paths did not cross. Comments HQ Air Command As with all Airprox involving Marham-based Tornados, this incident prompted an investigation on the unit. Whilst the incident itself was reasonably benign, it did highlight the fact that TCAS on Tornado is in its infancy, not only in terms of fleet fitment but also in terms of aircrew experience, and that the current TCAS employment guidance available to Tornado crews will need reviewing and trimming as the experience levels grow. Furthermore, this incident also reminds us that a busy frequency means that the controllers are working hard, and all crews should be prepared to increase their vigilance in terms of traffic detection and avoidance when operating in Class G airspace, irrespective of the ATS provided. In this instance the controller s assessment of projected separation in the climb did not equate to what the Tornado pilot saw out of the window and so he took action to maintain adequate, though slightly reduced, separation. Finally, it is disappointing that the Airprox was not declared on frequency, or at least a call made to Swanwick (Mil) after the mission, as the delay between submission of the DASOR and Swanwick being informed of the Airprox probably led to a loss of perishable evidence in the form of controller recollection. Summary An Airprox was reported when a Tornado formation and a C135 flew into proximity at 0946 on Monday 20 th April 2015 in the Class G airspace of the London FIR. Both crews were operating in VMC, The Tornado formation under VFR and the C135 crew probably under IFR, both in receipt of a Traffic Service from Swanwick Mil. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the pilots of both aircraft, transcripts of the relevant RT frequencies, radar photographs/video recordings, reports from the air traffic controllers involved and reports from the appropriate ATC and operating authorities. Considering the pilots actions first, the Board noted that both aircraft were in VMC, and that the pilots were in receipt of a Traffic Service from Swanwick (Mil), albeit from two different controllers. 2 SERA.3205 Proximity. 3 SERA.3210 Right-of-way (c) (2) Converging. 6

17 Airprox Members noted that, whether operating VFR or IFR, under SERA 4 the C135 pilot was required to give way to the Tornados in this situation. It was agreed that although the C135 pilot had ultimately taken avoiding action on the Tornados, this did not equate to giving way, especially since he had been given Traffic Information to assist him with this requirement at 8nm separation. The Board discussed whether the C135 pilot, not normally based in the UK, had been aware that he was under a Traffic Service (having reported under ATC vectors in receipt of a Deconfliction Service ), and also whether he was fully aware of the implications of such in Class G airspace. It was agreed that the suggested heading at 09:38:54 to remain clear of Holbeach range had probably amounted to ATC vectors in the C135 pilot s mind, and the likelihood that he thought he was under ATC vectors, might go some way to explaining him not giving way. During this discussion, military and civilian ATC members presented further anecdotal evidence of lack of understanding of UK FIS by pilots, and the routine imposition of unrequested services due to the need to avoid protracted RT conversations with those who were unfamiliar with UK FIS. It was agreed that UK FIS ATSOCAS provision was commonly misunderstood, or not understood at all, by many pilots, and that this was notably prevalent amongst those from outside the UK. The Board recalled making a number of previous recommendations in this respect concerning ATSOCAS provision and education, but that they had all been rejected 5. The Board also noted that the C135 pilot had reported being first alerted to the Tornados by a TCAS RA Descend but that he had in fact received Traffic Information on the Tornados at a range of 8nm. The USAFE member commented that this may be due to a failure of recollection given that the C135 crew had not been contacted to make a report until sometime after the event due to their being based overseas. The Board commented that this re-emphasised the requirement to make an Airprox call on the RT at the time, in order to cue the controllers and other pilot to record appropriate important information and circumstances before it became lost to memory. Members noted that after the C135 pilot had received a TCAS RA Descend he visually acquired the Tornado formation, made the decision to climb (because he perceived the Tornados to be descending on a conflicting flight path), and subsequently received an RA Climb whilst he was in the climb. Members agreed that the Board was poorly placed to analyse the time-critical decision process that the C135 pilot went through, but observed that civilian pilots are required to follow TCAS RA commands, irrespective of what they observe, in case the TCAS RA is being generated by an aircraft they have not seen. In this respect, it was further noted that TCAS was inherently subject to angle of arrival error, that the azimuth of a TA or RA may not have been related to that of the traffic observed outside, and hence that the pilot could easily have place himself in a situation where he was manoeuvering visually against traffic which was not in fact the cause of the TCAS RA. It was reasoned therefore that the safest course of action for the C135 pilot would have been to follow the TCAS RA as indicated, including any subsequent RA reversal. The Board also commented on the fact that, in this case, the lead Tornado had been equipped with TCAS but that the procedure at the time was to select TA-only when in formation; this had denied the Tornado pilot the benefit of a cooperative RA. Although there were sound reasons for selecting TAonly when conducting tactical manoeuvring with both aircraft in a formation squawking, the Board wondered whether the Tornado Force might wish to review their TCAS SOPs when aircraft were transiting as a single speaking unit with the No2 aircraft SSR normally set to standby. The Board noted that the Tornado formation had been passed Traffic Information on the C135 at 10nm, and that the No2 pilot had become visual with the C135. Although he had initially mis-asssesed the other aircraft s aspect, the lead pilot then saw the C135 and assessed that an immediate decent to FL140 was necessary. Members agreed that, ultimately, both pilots had resolved a conflict in Class G airspace, and that timely and effective action had been taken to prevent a collision. However, this Airprox highlighted a number of concerns regarding TCAS operation in an environment for which it was not specifically designed. If one aircraft was manoeuvered visually whilst the other was manoeuvered in response to a TCAS RA, then a situation could occur where the TCAS RA demanded manoeuvre might reduce 4 Standardised European Rules of the Air , and

18 Airprox separation and hence increased risk. Conversely, if a TCAS RA was not followed and the aircraft was manoeuvered with regard to what was assessed independently by the pilot as the conflicting traffic, potential mis-identification could again bring about loss of separation and hence increased risk. Notwithstanding operational considerations, members agreed that, in this case, at medium-level in Class G airspace, the safest course of action was to use TCAS as it was designed; in RA mode, and to follow any RAs which might be issued. PART C: ASSESSMENT OF CAUSE AND RISK Cause: A conflict in Class G resolved by both pilots. Degree of Risk: C. 8

19 AIRPROX REPORT No Date: 24 Apr 2015 Time: 1014Z Position: 5208N 00108E Location: Wattisham PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft Apache Model Glider Operator HQ JHC Unknown Airspace Lon FIR Lon FIR Class G G Rules VFR NK Service Basic None Provider Wattisham NK Altitude/FL 700ft NK Transponder A,C,S NK Reported Colours Black/Green White/yellow Lighting Strobes and Nil Nav lights Conditions VMC NK Visibility 30km NK Altitude/FL 700ft NK Altimeter QNH NK (1011hPa) Heading 250 NK Speed 100kt NK ACAS/TAS Not fitted NK Separation Reported 0ft V/50m H NK Recorded NK THE APACHE PILOT reports that he was flying straight-and-level at 700ft agl. The non-handlingpilot was heads-in when the rear-seat handling-pilot had to take avoiding action for a large model glider that was 2-3m in wingspan and estimated to be 50m from the aircraft. He described the model as white with yellow stripes and under fuselage markings, and reported it was aggressively manoeuvring. He rolled the aircraft rapidly to the right to avoid a collision and saw the glider turn left and descend. The incident was immediately notified to Wattisham ATC. He assessed the risk of collision as High. THE MODEL GLIDER OPERATOR could not be traced. THE WATTISHAM CONTROLLER reports he was the approach controller when the Apache reported a minor malfunction and returned to Wattisham from the East. As the Apache approached the MATZ boundary at approximately 700ft, the controller noticed it suddenly veered to the left. The pilot then reported taking avoiding action on a large model glider, with a wing span of 2-3m, possibly radio controlled, which had flown within 100m of his aircraft. The pilot sounded shaken by the event. There was no radar contact in the area, although the controller noted that the radar head for Wattisham is sited at Honington, some 15nm away, so it would be unlikely to see a small model aircraft at that level. He perceived the severity of the incident as High. 1

20 Airprox Factual Background The weather at Wattisham was reported as: METAR EGUW Z 22009KT CAVOK 15/06 Q1011 BLU NOSIG Analysis and Investigation Military ATM The Wattisham Approach controller recalled the Apache showing on radar at 700ft (QNH 1011 hpa) following a minor technical malfunction. At approximately 6nm east of Wattisham, the Apache was observed to veer left and the pilot reported an Airprox with a model glider. The controller did not see a radar contact in the vicinity of the Apache. The Supervisor commented that the Apache was between ft AGL and as the radar head was 15nm from the airfield, there was no expectation of seeing the model glider on radar. The Approach controller was providing a Basic Service to an aircraft returning to base, and the pilot was responsible for collision avoidance, as per CAP774. It is highly unlikely that a model glider would be detected by the radar and, given the low level and range from the radar head; it would not be expected to produce a return on the controller s radar display. Ultimately, for an aircraft not fitted with an ACAS, see-and-avoid was the only barrier to preventing a collision. UKAB Secretariat The Air Navigation Order 2009 (as amended), Article states: A person must not recklessly or negligently cause or permit an aircraft to endanger any person or property. Article 166, paragraphs 2, 3 and 4 state: Comments JHC (2) The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made. (3) The person in charge of a small unmanned aircraft must maintain direct, unaided visual contact with the aircraft sufficient to monitor its flight path in relation to other aircraft, persons, vehicles, vessels and structures for the purpose of avoiding collisions. (4) The person in charge of a small unmanned aircraft which has a mass of more than 7kg excluding its fuel but including any articles or equipment installed in or attached to the aircraft at the commencement of its flight must not fly the aircraft (a) in Class A, C, D or E airspace unless the permission of the appropriate air traffic control unit has been obtained; (b) within an aerodrome traffic zone ; or (c) at a height of more than 400 feet above the surface unless it is flying in airspace described in sub-paragraph (a) or (b) and in accordance with the requirements for that airspace. Having seen the glider, the AH crew carried out the correct avoiding action to minimise the risk to life. 1 Article 253 of the ANO details which Articles apply to small unmanned aircraft. Article 255 defines small unmanned aircraft. The ANO is available to view at 2

21 Airprox Summary An Airprox was reported on 24 April 2015 at 1010, between an Apache helicopter and a model glider. The Apache was returning to Wattisham at 700ft and receiving a Basic Service from Wattisham ATC when he encountered the glider at a similar level. The model glider did not show on the Wattisham radar so Traffic Information was not given. The Apache pilot estimated that the gilder was m away; the glider operator has not been traced. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of a report from the Apache pilot, transcripts of the relevant RT frequencies, radar photographs/video recordings, reports from the air traffic controllers involved and reports from the appropriate ATC and operating authorities. The Board noted that the Apache came into close proximity with the model glider in Class G airspace, just outside the Wattisham MATZ. However, because it was Class G airspace, and providing the model weighed less than 7kgs, the Board also noted that it was equally entitled to be there. The Board were informed that Wattisham ATC had contacted local model flying clubs, with which they had good relations, but that the model glider was not thought to be flying from one of these clubs. In looking at the actions of the glider operator, some Board members wondered whether the operator should have been able to hear the Apache approaching and could therefore have moved his glider out of the way. However, those with model flying experience thought that, although the operator might well have been able to hear the Apache, with the glider being at 700ft the operator would have needed to keep his eyes on the model in order to control it, and would be unlikely to be able to turn his sight away from the glider to also assess closure rates, geometry and the avoiding action required until the helicopter came into his line of sight. Simply descending the glider without sighting the Apache might equally have caused it to fly into conflict had the Apache been at a lower altitude. The Board commended the Apache pilot for his good look-out and subsequent avoiding action. Given the fact that the model would not show on radar, nor have any TAS/TCAS equipment on board, the only barrier to avoiding an Airprox with a model such as this was look-out; the Board agreed that it was likely that it had solely been his actions that had averted a collision. The cause of the Airprox was judged to be a conflict in Class G, resolved by the Apache pilot. The risk was assessed as Category B, avoiding action had been taken by the Apache pilot, but safety was much reduced below the normal. PART C: ASSESSMENT OF CAUSE AND RISK Cause: A conflict in Class G resolved by the Apache pilot. Degree of Risk: B. 3

22 Airprox AIRPROX REPORT No Date: 9 Apr 2015 Time: 1527Z Position: 5146N 00158W Location: 10nm SE Gloucester PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft Dauphin Glider Operator HQ JHC Unknown Airspace Lon FIR Lon FIR Class G G Rules VFR NK Service None NK Provider Gloster NK Altitude/FL FL25 NK Transponder A,C NK Reported Colours Blue/White White Lighting Strobes, nav NK and landing lights. Conditions VMC NK Visibility 4km NK Altitude/FL 3000ft NK Altimeter QNH NK (1024hPa) Heading 310 NK Speed 120kt NK ACAS/TAS TCAS I NK Alert Nil Separation Reported 0ft V/1000m H NK Recorded NK THE DAUPHIN PILOT reports that he was on a Procedural IRT sortie, VFR, at 3000ft. They had just left the Brize frequency, where they were receiving a Traffic Service, and had been handed-over to Gloster. Just prior to establishing communication with Gloster, a glider was seen m ahead, it was crossing and closing from the right. The instructor took control and made an avoiding action turn to the right. The glider did not register with TCAS and had not been reported by Brize Radar prior to handover. He assessed the risk of collision as High. THE GLIDER PILOT could not be traced. Factual Background The weather at Gloucestershire was reported as: EGBJ Z 13003KT 8000 FEW040 18/06 Q1023 Analysis and Investigation CAA ATSI The Dauphin helicopter was on a local IFR training detail. Just prior to the occurrence the aircraft was in receipt of an ATC service from Brize Radar. The Airprox occurred just after leaving the 1

23 Airprox Brize frequency and just before establishing communication with Gloster Approach. There is no mention of the Airprox on the Gloster frequency when communication was established. A review of the radar at the time reported did not provide any evidence of the Dauphin flight. However, there is a contact observed in the area an hour earlier which was squawking 3741 and whose history and altitude are consistent with the report. ATSI were advised that this code was assigned to the Dauphin. However, there was no evidence of any conflicting aircraft in the vicinity that was observed to affect the progress of this flight. Military ATM The Dauphin pilot was under a Traffic Service with Brize Radar but was in the process of a frequency change to Gloucester at the time of the incident. The Radar Analysis Cell could not capture the glider on any of the available radar replays, and the glider could not be traced. The controlling team at Brize were not made aware of the Airprox because the pilot had switched frequencies and they could not recall the event. The RT transcript was impounded when the unit were eventually informed of the incident. The Dauphin was placed under a Traffic Service by Brize Radar at 1525:55 upon leaving the Brize Zone, and traffic was called as, 12 o clock, 5 miles, crossing left to right, height unknown. The traffic was roughly in the BZN 286/15nm ( ). The traffic was not called again, and the Dauphin was transferred to Gloucester at 1527:22. The glider did not appear on the radar replay, and the CPA was estimated at 1528:01. It is not known if the traffic called by Brize was the Airprox glider, and there is limited information from the control team. The controller had updated the service to the Dauphin upon leaving CAS, and had called traffic prior to the frequency change to Gloucester. The normal barriers to an Airprox in Class G airspace would be Traffic Information, ACAS and see-and-avoid. Traffic Information had been provided on non-squawking traffic; however, it was not known if the information related to the Airprox glider, or if the glider had appeared on the Brize radar. TCAS did not provide an alert, and the radar replay did not detect a transponding aircraft in the area. One of the Dauphin pilots was flying on instruments, and the instructor was solely responsible for the lookout. Ultimately, the instructor visually acquired the glider and took avoiding action to maintain safe separation. UKAB Secretariat Both pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 1. When two aircraft are converging at approximately the same level, the aircraft that has the other on its right shall give way, except as follows: (i) power-driven heavier-than-air aircraft shall give way to sailplanes... 2 Comments JHC This occurred in Class G airspace and highlights the fact that a Traffic Service cannot necessarily give accurate detail of all traffic, especially those that are not transponding. JHC are continuing to investigate the inclusion of FLARM displays in ATC, providing an additional safety barrier. Crews have recently been educated to view Glidernet to highlight major glider concentrations prior to departure. In this case, the non-handling pilot saw the glider early, and carried out the correct action to prevent the conflict developing further. 1 SERA.3205 Proximity. 2 SERA.3210 Right-of-way. 2

24 Airprox BGA With 1-2km separation in Class G airspace, it is unlikely that the glider pilot would have considered this to be an Airprox. Summary An Airprox was reported on 9 th April at 1529 between a Dauphin helicopter and a glider. The Dauphin had just left the Brize frequency and had not yet established contact with Gloster so did not receive any Traffic Information. The instructor saw the glider and took avoiding action by turning to the right. The glider did not show on the NATS radars and could not be traced. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the Dauphin pilot, transcripts of the relevant RT frequencies, radar photographs/video recordings and reports from the appropriate ATC and operating authorities. The Board first considered the actions of the Dauphin pilot. The Board noted that Brize Radar had given Traffic Information on traffic prior to the Dauphin leaving their frequency, but whether this was on this glider or another aircraft it was impossible to tell. It was unlikely that the glider had any form of TCAS and, although it could have been fitted with FLARM, this wouldn t have been compatible with TCAS which would therefore explain why the Dauphin pilot hadn t received any TCAS derived Traffic Information. The Board noted that both aircraft were flying in Class G airspace where see-and-avoid was the main mitigation against mid-air collision, both aircraft were entitled to be there, and that seeand-avoid had worked in that the Dauphin pilot at least had seen the other aircraft in enough time to take appropriate action before the situation closed to closer proximity. Noting the JHC comment regarding Glidernet, the Board wished to commend them on highlighting the usefulness of Glidernet to pilots prior to getting airborne, and they also made comment that, although clearly not usable specifically as a controlling tool due to time lag and other certification complications, Glidernet had great potential value to ATC in providing general situational awareness of gliders which may not be otherwise detectable by radar. The Board commented that it was unfortunate that the glider hadn t shown on the NATS radars, and therefore that the pilot couldn t be traced in order to provide his version of events. This sparked off a frequently held discussion by the Board about radar conspicuity of gliders, and the possibility of fitting radar reflectors in the aircraft. The Board heard about some of the difficulties of sighting a reflector in the airframe and that, regretfully, this aspiration was no further forward. The Glider Board member reported that the BGA were keen to encourage pilots to talk to each other and ATC either by calling on radios when airborne, or calling up units by telephone prior to getting airborne. Citing education and dialogue as a key resource in understanding the needs and requirements of other airspace users, they were also keen to ensure gliding clubs adopted good relations with neighbouring airfields, and attended local airspace user groups whenever possible. The Board noted that it was entirely appropriate that a report had been raised by the Dauphin pilot which highlighted the need for good look-out and awareness in all phases of flight. In assessing the cause of the Airprox, they agreed that it was a sighting report and that, given the actual proximity once action had been taken; they decided that the risk was Category E, normal safety standards and procedures had pertained. PART C: ASSESSMENT OF CAUSE AND RISK Cause: A sighting report. Degree of Risk: E. 3

25 AIRPROX REPORT No Date: 25 Apr 2015 Time: 1508Z Position: 5131N 00231W (Saturday) Location: 11nm NE Bristol Airport PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft Lynx Drone Operator RN Unknown Airspace London FIR Class G Rules VFR Service Basic Provider Bristol Altitude/FL 2500ft Transponder A, C, S Reported Colours Grey/Green Lighting NK Conditions VMC Visibility 10km Altitude/FL 2100ft Altimeter QNH (1005hPa) Heading 360 Speed 120kt ACAS/TAS Not fitted Separation Reported 0ft V/40ft H Recorded NK THE LYNX PILOT reports transiting to RNAS Yeovilton. The aircraft was descending from 2500ft to 1500ft when a small white doughnut shaped UAV/drone was observed directly ahead at a range of approximately m. The pilot conducted an evasive manoeuvre, a right-hand break, and the UAV passed 30-50ft (approximately 1 rotor span) down the left-hand side. The pilot stated that the object appeared to be about 50cm across, with a mass of less than 7kg he estimated, and appeared to remain level without manoeuvring. It was difficult to see against an urban backdrop but a low cockpit workload allowed an effective lookout scan. The pilot also commented that had the UAV not been sighted through effective lookout, and evasive action not been taken, a mid-air collision would have occurred. He assessed the risk of collision as Very High. THE DRONE OPERATOR: The drone operator could not be traced. THE BRISTOL CONTROLLER reports the Lynx pilot was in receipt of a Basic Service and declared an Airprox with a UAV whilst outside CAS, about 11nm northeast of Bristol airport. Factual Background The weather at Bristol was recorded as follows: METAR EGGD Z 25008KT 9999 FEW033 BKN045 13/08 Q1005 1

26 Airprox Analysis and Investigation UKAB Secretariat The Air Navigation Order 2009 (as amended), Article states: A person must not recklessly or negligently cause or permit an aircraft to endanger any person or property. Article 166, paragraphs 2, 3 and 4 state: (2) The person in charge of a small unmanned aircraft may only fly the aircraft if reasonably satisfied that the flight can safely be made. (3) The person in charge of a small unmanned aircraft must maintain direct, unaided visual contact with the aircraft sufficient to monitor its flight path in relation to other aircraft, persons, vehicles, vessels and structures for the purpose of avoiding collisions. (4) The person in charge of a small unmanned aircraft which has a mass of more than 7kg excluding its fuel but including any articles or equipment installed in or attached to the aircraft at the commencement of its flight must not fly the aircraft (a) in Class A, C, D or E airspace unless the permission of the appropriate air traffic control unit has been obtained; (b) within an aerodrome traffic zone ; or (c) at a height of more than 400 feet above the surface unless it is flying in airspace described in sub-paragraph (a) or (b) and in accordance with the requirements for that airspace. A CAA web site 2 provides information and guidance associated with the operation of Unmanned Aircraft Systems (UASs) and Unmanned Aerial Vehicles (UAVs). Additionally, the CAA has published a UAV Safety Notice 3 which states the responsibilities for flying unmanned aircraft. This includes: Comments You are responsible for avoiding collisions with other people or objects - including aircraft. Do not fly your unmanned aircraft in any way that could endanger people or property. It is illegal to fly your unmanned aircraft over a congested area (streets, towns and cities). Also, stay well clear of airports and airfields. Navy HQ Mid-Air Collision between manned aircraft and unmanned aerial systems is in the Navy HQ top 5 risks to life. On this occasion a catastrophic collision was only avoided by the aircrew s final safety barrier of see and avoid. This type of incident between manned aircraft and unmanned systems are becoming more prevalent and the next incident might not be a near miss but a collision. Current regulations pertaining to the operation of drones are difficult to enforce given the ease with which drones can be purchased; however, it is important that interested UK stakeholders continue to work together to ensure that any risk to manned aerial systems posed by drone operations can be considered ALARP [UKAB Note: As Low As Reasonably Practical]. 1 Article 253 of the ANO details which Articles apply to small unmanned aircraft. Article 255 defines small unmanned aircraft. The ANO is available to view at CAP

27 Airprox Summary An Airprox was reported when a Lynx and a drone flew into proximity at about 1508 on Saturday 25 th April The Lynx pilot was operating under VFR in VMC in receipt of a Basic Service from Bristol. The drone operator could not be traced. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of a report from the Lynx pilot, radar photographs/video recordings, a report from the air traffic controller involved and a report from the appropriate operating authority. Members quickly agreed that the drone had been flown into conflict with the Lynx by being operated in a location from which it should not have been operated, namely over a heavily populated area, and at an altitude above that permitted by regulation. The Board thought that the drone was likely either there because the operator had lost control of it, or was being flown using a First-Person-View or automated control system with attendant lack of lookout capability. It was also agreed that regulation to prevent the operation of drones in such circumstances already existed, and that it was noncompliance with the pertinent regulation which had created the safety risk. Members expressed frustration and concern at the rapidly increasing number of Airprox involving drones, of which the majority involved drone operators apparently conducting their activities either by mistake, in ignorance, or in deliberate contravention of the regulations. In whatever regard, the regulations were both not being adhered to nor being enforced effectively, and members expressed their concern that the situation should not be allowed to continue without action being taken to reduce the prospect of an aircraft being brought down by a drone strike. 4 Some members felt that it was for the CAA to implement better regulation whilst others felt that sufficient regulation already existed and that it was greater enforcement that was required. In this latter respect, members noted that Airprox had generated a recommendation that The CAA liaise with the National Police Chiefs Council to clarify Police response to ATC reports of Airprox involving drones. Members were hopeful that this would provide clarity on what the response to drone reports was, and to what extent the Police and CAA kept records for subsequent enforcement of regulation and proactive education/risk reduction. Members opined that this was a similar issue to laser attacks, and should be treated in a similar manner. The Board re-iterated that drone use was quite rightly open to all within the bounds of regulation, but that this included those with no knowledge, or desire to gain knowledge, as to their correct and safe operation. This ubiquity carried with it potentially significant risk, and it was the responsibility of all those involved in regulation and enforcement to mitigate that risk to the appropriate level to help reduce the prospect of collisions. When assessing the risk, some members felt that the Lynx pilot had simply manoeuvered sufficiently such that he had prevented collision, albeit with safety margins much reduced below the normal. Others felt that the situation had only just stopped short of an actual collision. After some discussion, the Board were persuaded by the Lynx pilot s report, and decided, by a majority, that the separation achieved had been reduced to the minimum and that chance had played a major part in events. PART C: ASSESSMENT OF CAUSE AND RISK Cause: The drone was flown into conflict with the Lynx. Degree of Risk: A. 4 In respect of drone strikes the Board was informed that ongoing research indicated that the density and rigidity of a drone was such that the damage mechanisms in a drone strike were more serious than those in a bird strike. The lack of deformation of a drone during impact was such that it was more likely to damage engines or primary structures, and could penetrate the cockpit with more serious degrees of injury to occupants. This was a particular risk to rotorcraft with large forward-facing glazed areas and where relatively minor damage to rapidly rotating rotorhead or tail rotor components could result in out-of-balance forces sufficient to result in catastrophic failure and loss of control of the aircraft. 3

28 Airprox AIRPROX REPORT No Date: 1 May 2015 Time: 18.02Z Position: 5329N 00024W Location: North Kelsey, Lincs PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Aircraft 1 Aircraft 2 Recorded Aircraft AW139 Para-Motor Operator Civ Comm Unknown Airspace London FIR London FIR Class G G Rules IFR NK Service Traffic NK Provider Humberside NK Altitude/FL 2000ft NK Transponder A,C NK Reported Colours White/Blue/Red Red Lighting Nav, Anti-Colls Nil Conditions VMC NK Visibility >10km NK Altitude/FL 2000ft NK Altimeter QNH NK (1012hPa) Heading 023 NK Speed 120kt NK ACAS/TAS TCAS I NK Alert Nil Unknown Separation Reported 200ft V/100m H NK Recorded NK THE AW139 PILOT reports that he had just reached the descent point for the NDB approach to RW02 when the non-handling pilot called contact! as he became aware of a paramotor, with a red canopy and one engine, slowly moving right-to-left across the nose of the aircraft at the range of 600m and 100ft below. The aircraft was immediately decoupled [from autopilot] and an emergency turn carried out to avoid the paramotor; they passed it 100m right and 200ft below in order to maintain visual contact at all times and in the hope that it would make him aware of their presence and his location. ATC were informed and a visual approach was carried out. He assessed the risk of collision as High. THE PARA-MOTOR PILOT could not be traced. THE HUMBERSIDE CONTROLLER reports that the AW139 was returning from offshore to Humberside and had been cleared for the NDB/DME procedure for RW02. Once the pilot called established on the approach track, he was cleared to descend in accordance with the procedure. Shortly afterwards the pilot reported taking avoiding action against a para-glider ahead of him, at approximately 4nm finals for RW02. The controller acknowledged and attempted to locate a radar return for the para-glider. The AW139 pilot reported clear of the conflicting traffic and switched to the Tower frequency to continue the approach visually. The controller then managed to locate a faint, intermittent primary contact in the vicinity which tracked slowly north-westerly, before turning southeast. The Tower controller gained visual contact and confirmed it was a para-glider. 1

29 Airprox Factual Background The weather at Humberside was reported as: EGNJ 1750z 070/ SCT030 08/02 Q1012 Analysis and Investigation CAA ATSI The AW139 Helicopter was returning from offshore and had been cleared for a NDB/DME approach to RW02 at Humberside. The A139 was in receipt of a Traffic Service from Humberside Radar. As the AW139 approached a 4-mile final, the pilot reported to ATC that he was taking avoiding action on a para-glider which was approximately 100ft below and 600 metres ahead. The Radar controller was able to locate a faint contact in the vicinity after the AW139 had passed. It is not clear whether this was visible on radar before but, because of the nature of such an aircraft, the return would be weak and would be based upon primary radar only. It is also likely that there would have been no discernible track information (history) due to the slow movement. Humberside does not have any controlled airspace and the range at which the AW139 encountered the paramotor was outside of the ATZ. The provision of a Traffic Service does not require a controller to achieve a deconfliction minima and the avoidance of other traffic is the pilots responsibility. 1 There was no evidence of the para-motor on the MRT Radar recording available to ATSI. UKAB Secretariat Both pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 2. When two aircraft are converging at approximately the same level, the aircraft that has the other on its right shall give way. Comments BHPA As the paramotor pilot has not been traced, the BHPA cannot comment upon the training that the pilot may, or may not, have received about the feathers depiction on the chart. It could have been an off-duty ATPL or military pilot at one extreme or a completely self-taught Ebay'er at the other. The BHPA has long recognised that paramotor pilot training is almost infinitely variable and as part of the current ANO review has resubmitted the proposal 3 that it first made to the CAA some 10 years ago. Contact from the CAA is awaited so that it can then hopefully be pursued and the minimum quality of training be raised to an acceptable standard. With respect to the poor radar display of the paramotor the BHPA is awaiting a response from the CAA's Conspicuity Working Group, which amongst others includes NATS, on the different capabilities and configurations of radars in the UK, particularly with respect to slow moving targets. The lack of a prompt response plus previous comments from various ATC units leads us to wonder as to the consistency of current practices and standards and whether there is the possibility for national-level improvements. 1 CAP493 Section 1 Chapter 12 2 SERA.3205 Proximity. 3 A proposal that the CAA mandate that the pilots of all manned civil aircraft in the UK are required to hold a qualification that demonstrates an acceptable level of knowledge of UK Air Law and airspace. The BHPA already has a proven certification system in place that could be used as a minimum legal requirement. 2

30 Airprox Summary An Airprox was reported on 1 st May at 1802 between an AW139 and a paramotor. The AW139 was on the NDB approach to Humberside when the pilot saw the paramotor approximately 600m in front of his aircraft. He took avoiding action and then converted to a visual approach. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the AW139 pilot, transcripts of the relevant RT frequencies, radar photographs/video recordings, reports from the air traffic controllers involved and reports from the appropriate ATC and operating authorities. The Board first looked at the actions of the paramotor pilot. They acknowledged that he was perfectly entitled to be where he was, in Class G airspace, but commented that although he was crossing the approach feathers at right angles for the quickest crossing, it was unfortunate that his height was exactly that of someone descending on the glide-path. They opined that he would have been better served in arranging his flight to be either higher, or lower, at that particular point. The Board were disappointed that the pilot could not be traced, and it was noted that the local clubs that were mentioned in Humberside ATC report had confirmed that he was not operating from them that day. As commented by the BHPA, members highlighted the fact that this illustrated that it was quite feasible for a paramotor pilot to operate autonomously and therefore miss out on vital lessons and experience brought about by being a member of a club. Without being able to gain the paramotor pilot s perspective, the Board were unable to determine whether he had seen or heard the AW139 which, being initially above the paramotor was likely to have been obscured by the paramotor canopy. It looking at the actions of the AW139 pilot, the Board noted that the incident had happened at a point of high workload when it was likely that the pilots were looking into the cockpit to check their instruments and could well have become task-focused. Furthermore, they opined that it can be difficult to see small aircraft when viewed from above, because it would merge into the landscape below. Despite the inopportune positioning of the paramotor, in accordance with SERA the AW139 pilot was required to give-way, which he did by executing an emergency avoiding action turn, albeit at a relatively late stage. In discussing the cause of the Airprox, the Board agreed that it was a late sighting by the AW139 pilot; the associated risk was assessed as Category C, timely and effective action had been taken. Recognising that the paramotor pilot may not be part of the BHPA or club communities, the Board felt that it would be helpful nonetheless to highlight the issue of airfield approach lanes to the wider community perhaps through magazine articles etc. As a result, the Board felt that the Airprox warranted a recommendation that the BHPA consider measures to educate paramotor pilots on best practice for crossing airfield approach lanes. PART C: ASSESSMENT OF CAUSE AND RISK Cause: A late sighting by the AW139 pilot. Degree of Risk: C. Recommendation: The BHPA consider measures to educate paramotor pilots on best practise for crossing airfield approach lanes. 3

31 AIRPROX REPORT No Date: 2 May 2015 Time: 1143Z Position: 5213N 00013E Location: Cambridge Airport (Saturday) PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft EMB170 PA28 Operator Civ Trg Civ Trg Airspace Cambridge ATZ Cambridge ATZ Class G G Rules VFR VFR Service Aerodrome Aerodrome Provider Cambridge Cambridge Altitude/FL 1100ft 1000ft Transponder A/C/S A/C Reported Colours Company White/grey/red colours Lighting Navigation, anti-collision. Strobes u/s. Beacon, strobes, landing. Conditions VMC VMC Visibility >10km 10km Altitude/FL 1100ft 1000ft Altimeter QNH QFE (1011hPa) Heading 055 Orbit Speed 140kt 95kt ACAS/TAS TCAS II Not fitted Alert RA N/A Separation Reported 0ft V/<1nm H NK Recorded 0ft V/0.4nm H THE EMB170 PILOT reports that, whilst on the climb-out after a touch-and-go during circuit training, a TCAS RA to maintain vertical speed was received. Whilst on the approach, ATC had requested that they change to a left-hand circuit. He believed this was to allow the (ultimately conflicting traffic) to join downwind right-hand. He was comfortable accepting this as it had minimal impact on their workload. On receipt of the TCAS RA he followed the commands and, during this time, the jumpseat pilot was able to visually acquire the traffic. Once clear of the RA, ATC were advised, and a left turn (away from the traffic and into the cleared circuit) was initiated. The circuit clearance of 2000ft was exceeded by 300ft during the recovery from the TCAS manoeuvre. On the approach, they were aware of the traffic, and the change of sequencing proposed by the Aerodrome controller seemed reasonable avoiding conflict. For obvious reasons during the later stages of the approach, touchand-go and subsequent climb-out, the workload was high requiring a degree of reliance on the clearance received. The pitch attitude is also very high at this point, restricting forward view from the left-hand seat, particularly in the area of the conflicting traffic. During the initial climb, and prior to the TCAS event, he was aware of the Aerodrome controller giving an update on their position. A response along the lines of I m sure they ll have us on their TCAS was transmitted but he did not know if it was from the conflicting aircraft s pilot. He assessed the risk of collision as Medium. 1

32 Airprox THE PA28 PILOT reports that, on returning from a flight to the east of Cambridge airport, ATC asked him to join downwind for RW05. Knowing the airport s required circuit plan he joined by the Quy 1 roundabout at 1000ft QFE. He was then asked to orbit as another aircraft was already orbiting further downwind. On completion of the second orbit he saw the reporting aircraft lifting off the runway, but he was unable to exit his track due to his forward speed and the relatively low speed of his aircraft, coupled with the westerly [he reported] wind at the time. Separation distance was not assessable as the reporting aircraft was behind him and out of sight. He assessed the risk of collision as Low. THE CAMBRIDGE AERODROME CONTROLLER reports that he was operating with a trainee. The PA28 pilot was transferred from the Approach controller to the Aerodrome controller passing Newmarket. The pilot was asked to descend to height 1000ft and report reaching, to join downwind left-hand RW05 and was passed Traffic Information on an EMB170 conducting right-hand circuits at altitude 2000ft. The pilot replied that he had read about the EMB170 in the circuit prior to his flight and questioned the joining instructions. The trainee controller corrected the joining instructions to join downwind right-hand. This had been a slip of the tongue due to downwind left-hand being the standard join for Cambridge s predominant runway (23). Due to a Tiger Moth orbiting at the end of the downwind leg for wake turbulence purposes, the PA28 pilot was instructed to take up orbits at the start of the downwind leg. Due to the complexity of the wake turbulence issues he changed his plan and gave the EMB170 pilot instructions to fly the next circuit left-hand to sequence the traffic more efficiently and safely. With the EMB170 on final, Traffic Information was passed on the PA28 joining downwind right-hand for RW05 because he appeared to be encroaching towards the RW05 climb-out path. He then cleared the EMB170 pilot for a touch-and-go. The PA28 pilot reported taking up lefthand orbits late downwind for RW05, at which point the trainee controller corrected him on his position and said take up orbits at the start of the downwind leg. He took control from his trainee again and told the PA28 pilot to route to the east to clear the climb-out, and passed Traffic Information on the EMB170 who was just getting airborne from his touch-and-go. The PA28 pilot refused the instruction and informed them that he was orbiting at Quy Mill which is on the climb-out for RW05 inside the ATZ. He then remarked that the EMB170 s TCAS would inform its pilot of his position. By this time the aircraft were in close proximity and avoiding action from the Tower was not issued due to being unable to see clearly the correct action to be taken without potentially making the situation more serious. The EMB170 pilot reported receiving a TCAS RA by the time they could see a clear course of action so no other information was needed. Both he and his student were immediately relieved from the position and the EMB170 pilot reported to the oncoming controller a miss distance of ft. Factual Background The Cambridge weather was: EGSC KT 020V FEW032 10/04 Q1011 The Cambridge Aerodrome Traffic Zone, Class G airspace, is a circle 2.5nm radius centred on the longest notified runway (05/23) from surface to 2000ft 2. Airfield elevation is 47ft. Unless otherwise instructed by Air Traffic Control the visual circuit height is 1500ft for all multi-engined types, 1000ft for other fixed-wing aircraft and 700ft for helicopters. All heights QFE. The following circuit directions will be adhered to: Runways 23, 28 left hand; Runways 05, 10 right hand. The above procedures may be departed from at any time to the extent necessary for avoiding immediate danger. 3 1 Junction of A14/A1303 approximately 1nm east of airport. 2 UK AIP AD 2.EGSC-8. 3 UK AIP AD 2.EGSC-11. 2

33 Airprox Analysis and Investigation CAA ATSI The EMB170 pilot was operating in the right-hand circuit for RW05. The PA28 pilot had departed Cambridge to the north-east approximately 20min earlier and was returning from that direction. The controller elected to route the EMB170 pilot into a left-hand circuit to accommodate the arrival of the PA28 from the north-east into a right-hand circuit. The PA28 pilot was cleared into the right-hand circuit at 1139:40. This tactic should have enabled the best flow of traffic around the ATZ. The PA28 pilot was issued with Traffic Information on the EMB170 in order for the pilot to position himself directly downwind from the north-east; the pilot confirmed he knew about the jet in the circuit. As the PA28 approached Cambridge from the north-east he was observed to be tracking towards the climb-out from RW05 (Figure 1 at 1142:02). Figure 1 (1142:02) (EMB at FL003, PA at FL011). The controller had one other aircraft in the circuit (also right-hand) so instructed the PA28 pilot to orbit left at the beginning of the downwind leg at this time. As there appeared to be no turn by the PA28 pilot, the controller instructed him to move further to the east; however, the aircraft did not appear to adjust course. [UKAB Note: the PA28 pilot responded to the intial request to orbit at the start of the downwind leg by stating that he would do so adjacent to the Quy roundabout, which is near the start of the downwind leg. The controller then asked him to orbit just a little bit further to the east at 1142:30]. [At 1142:40] the PA28 pilot then stated that he could see the other aircraft and commented that the EMB170 pilot would be able to see his aircraft on TCAS. [At 1142:50, the PA28 pilot called that he was commencing his orbit]. As the EMB170 pilot took-off following a touch-and-go, he came into close proximity to the PA28 (Figure 2 at 1143:02). 3

34 Airprox Figure 2 (1143:02) After passing the PA28 the EMB170 pilot reported a TCAS RA and subsequently filed an Airprox. The PA28 pilot then began a left-hand orbit. Although the airspace around Cambridge Airport is Class G, all aircraft flying within the ATZ are required to comply with ATC instructions. Occurrence Investigation RTF recording of Cambridge Aerodrome control: PA28 ATC PA28 ATC PA28 ATC PA28 EMB170 ATC EMB170 ATC Cambridge ( ) Tower (PA28 C/S) is er over Newmarket two thousand five hundred for rejoin. (PA28 C/S) Cambridge Tower descend now to report level ( ) alti-er correction at height one thousand feet Cambridge QFE one zero zero nine join downwind lefthand at one thousand. Er (PA28 C/S) descending to ( ) one thousand feet one one zero to join downwind lefthand confirm. Apologies downwind righthand. Downwind righthand thank you very much (PA28 C/S) ( ) and to join downwind righthand runway er zero five. (PA28 C/S) traffic s an Embraer One Seventy in the circuit will be at two thousand feet to keep him above you for wake turbulence ( ). Er I was aware of all that er (PA28 C/S) thanks very much for the reminder. (EMB170 C/S) we re er final zero ( ) five touch and go. (EMB170 C/S) are you able to accept a lefthand circuit after this touch and go. (EMB170 C/S) affirm. (EMB170 C/S) roger runway (1141) zero five main clear touch and go surface wind one four zero degrees nine knots a lefthand circuit. 4

35 Airprox EMB170 EMB170 ATC EMB170 PA28 ATC Clear touch and go runway zero five main and a lefthand circuit (EMB170 C/S). (EMB170 C/S) er what altitude for this lefthand circuit. (EMB170 C/S) altitude two thousand ( ) feet. Altitude two thousand feet (EMB170 C/S). Er (PA28 C/S) now at one thousand feet approaching the end of the downwind leg. (Take up?????????? spoken off mic) (PA28 C/S) take up one lefthand orbit at the start of the downwind leg. PA28 Take up one orbit er adjacent to QUY roundabout roger ( ). ATC PA28 (PA28 C/S) you can do it just a little bit further out to the east ( ) that Embraer s just on climbout now we ll be taking him into the lefthand visual circuit. I can see him er (PA28 C/S) thank you very much and I m sure his TCAS will tell him about me ( ). ( ). PA28 (PA28 C/S) commencing orbit. (1143). EMB170????? ( ) and (EMB170 C/S) we got an RA off that one. ATC (EMB170 C/S) thanks I ll be filing on that as well ( ). UKAB Secretariat Both pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 4. Both pilots were required to observe other aerodrome traffic for the purpose of avoiding collision and to conform with or avoid the pattern of traffic formed by other aircraft in operation 5. CAP 493 (Manual of Air Traffic Services Part 1) states 6 : Clearance to enter a traffic circuit is issued when an aircraft is still some distance from the aerodrome to enable the pilot to conform with the traffic circuit, pending clearance to land. Information concerning landing direction or runway in use and any other necessary instructions are given at the same time so that the pilot may intelligently position himself in the traffic pattern. Aircraft within an ATZ are required to comply with instructions from the ATC unit. Although IFR/VFR flight within Class F/G airspace outside the ATZ is permitted without an ATC clearance, controllers will act on the basis that pilots will comply fully with their instructions in order to promote a safer operating environment for all airspace users. 4 SERA.3205 Proximity, Rules of the Air SERA.3225 (a), (b) Operation on and in the Vicinity of an Aerodrome, Rules of the Air Section 2, Chapter 1, Paragraph 18 and Section 3, Chapter 1, Paragraph 1B.2. 5

36 Airprox Comments THE FLYING CLUB OPERATING THE PA28 reports that an incident meeting has been held between the flying club and Cambridge ATC representatives to determine the events that contributed to the Airprox and to formulate an appropriate training response for both the pilot involved and other club members. From the various inputs received, the main factor appears to have been a misunderstanding of instructions from ATC by the PA28 pilot and the club has arranged recurrent training for the pilot involved to clarify the radio and TCAS procedures which will also be passed on to club members. As the club duty manager on the day he believed that the unusually large number of aircraft and ground traffic movements due to a racing event bringing in extra helicopter, private aircraft and wide-body movements with the associated ground vehicles were a contributory factor to the incident. This, in addition to the usual weekend club, Tiger Moth, private flying, ATC training and the EMB170 pilot flying circuits throughout the day led to an unusually high workload for both pilots and ATC and some associated delay and confusion in RT. Although the scheduling for these days is not always exact, ATC has agreed to try and circulate any detailed information received in advance to allow other airport users to plan training flights and departures accordingly. Summary The Airprox occurred within Class G airspace of the Cambridge ATZ; both pilots were in receipt of an Aerodrome Control Service. The EMB170 pilot had been conducting circuit training to RW05 and the PA28 pilot was inbound to Cambridge from the north-east after a local flight. He was instructed to join downwind right-hand for RW05 and to orbit at the start of the downwind leg due to other traffic holding ahead - Traffic Information was issued to him about the EMB170 in the right-hand circuit. The controller then decided to clear the EMB170 pilot for a left-hand circuit after his touch-and-go. When the EMB170 pilot was on final approach Traffic Information was issued about the PA28 which appeared to be approaching the RW05 climb-out. The controller instructed the PA28 pilot to route further east and updated the Traffic Information to the EMB170 pilot as he commenced his take off from the touch-and-go. The EMB170 pilot subsequently reported having received a TCAS RA. The minimum distance between the aircraft was recorded as nil vertical and 0.4nm horizontal. PART B: SUMMARY OF THE BOARD S DISCUSSIONS Information available included reports from both pilots, the controller concerned, area radar and RTF recordings and reports from the appropriate ATC and operating authorities. The Board noted that there were some incorrect recollections of the incident by the PA28 pilot and the Cambridge Aerodrome controller. The radar and RTF recordings of the event were able to reveal to the Board the actual course of events leading up to the Airprox. The Board considered that the controller had taken appropriate action when he had changed the circuit direction of the EMB170 to a left-hand circuit. This had allowed the aircraft to remain clear of slower traffic ahead in the right-hand circuit. The controller had issued Traffic Information to the EMB170 and the PA28 pilots, accordingly both pilots had been aware of the presence of the other traffic. The Board noted that the controller recollected that he had instructed the PA28 pilot to orbit at the start of the downwind leg before he had cleared the EMB170 pilot for a touch-and-go. However, the RTF recording shows that the EMB170 pilot had been cleared for a touch-and-go before this instruction had been issued. The Board were aware from the controller s report that in his opinion the PA28 pilot had positioned too close to the RW05 climb-out and, understandably, had requested him to route further out to the east. It was also noted that he had reported that the pilot had refused to carry out this action but this was not evident from the RT transcript. The Board then discussed the actions of the PA28 pilot. He recollected that he had seen the EMB170 lifting off the runway on completion of his second orbit whereas the radar recordings show that the CPA occurred before the PA28 pilot had commenced any orbit. He also commented that he had been unable to report the separation distance because the EMB170 had been behind him and 6

37 Airprox out of sight at the time of the Airprox. The radar recordings show that it had actually been passing alongside him at CPA as he had been proceeding downwind. Members spent much time discussing the recollections of both the pilot and the controller, and there was considerable debate and difference of opinion about whether the PA28 pilot had complied with the controller s request to orbit further out to the east. Some members believed that there appeared to have been some ambiguity in this request, and that the pilot was required simply to route a little further east than Quy roundabout. Other members believed he should have taken up an easterly heading straight away rather than route towards Quy roundabout at all. After much debate, because the radar recordings showed that he had in fact changed direction at the time from a westerly to a south-westerly track, other members thought that, in carrying out this action, he had effectively complied with the controller s request, namely he had been at a position further east than he would have been had he maintained his original track to Quy roundabout - in his mind, he was probably still complying with the spirit of the instruction to orbit at the start of the downwind leg. Notwithstanding, the Board agreed that his change of direction still resulted in the PA28 routeing towards the EMB170, and they were disturbed that the PA28 pilot s comments about the EMB170 pilot seeing him on TCAS could be construed as him placing collision avoidance responsibility on the EMB170 pilot. Rather than relying on the EMB170 pilot reacting to his TCAS, the Board considered that the PA28 pilot should have routed further away from the RW05 climb-out in the first place. Finally, the Board noted that the PA28 pilot had reported commencing an orbit at 1142:50, just before the Airprox had occurred at 1143:02. The Board considered that it had been the actions of the PA28 pilot that had caused the Airprox. Despite being aware of the EMB170 s details, and having had the aircraft in sight, he had positioned into the downwind leg too close to the EMB170 pilot s climb-out from RW05 and therefore had triggered the TCAS RA. Consequently it was considered that the cause was that the PA28 pilot had flown into confliction with the EMB170. Although the minimum recorded separation was only 0.4nm horizontally (at the same level), the Board considered that risk of collision had been averted. The PA28 pilot had reported on the frequency just prior to the CPA that he had been visual with the EMB170, and the EMB170 pilot had received and had reacted to a TCAS RA to maintain vertical speed with the jump-seat pilot also reporting that he had seen the PA28. Therefore, because of the visual sightings and the TCAS RA manoeuvre, the Airprox was categorised as risk Category C. PART C: ASSESSMENT OF CAUSE AND RISK Cause: The PA28 pilot flew into conflict with the EMB170. Degree of Risk: C. 7

38 Airprox AIRPROX REPORT No Date: 4 May 2015 Time: 1405Z Position: 5142N 00001W Location: IVO Waltham Abbey PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft PA28 Spitfire Operator Civ Pte Civ Pte Airspace Lon FIR Lon FIR Class G G Rules VFR NK Service Basic NK Provider Luton NK Altitude/FL 1700ft NK Transponder A,C,S NK Reported Colours Cream/Brown WWII markings Lighting Strobes/tail NK beacon Conditions VMC NK Visibility >10km NK Altitude/FL 1600ft NK Altimeter QNH NK (1003hPa) Heading 128 NK Speed 120kt NK ACAS/TAS Not fitted NK Separation Reported 500ft V/0m H NK Recorded NK V/0.2nm H THE PA28 PILOT reports that he was at 2000ft receiving a Basic Service from Luton, when they gave Traffic Information on traffic 12 o clock, 2 miles, no height information ; he became visual with a Spitfire in a steep dive crossing right to left, below him. The aircraft levelled at a very low altitude and, because he was not concerned by its proximity, he set 7000 squawk and changed frequency to Stapleford. Before he could establish RT contact, the Spitfire started to climb and turn towards him, so he took evasive action by descending rapidly. The Spitfire continued to climb and turn, passing directly overhead at approximately 500ft above (with the base of the London TMA at 2500ft). The PA28 pilot levelled at 1600ft, maintained visual contact until the aircraft passed directly overhead, then re-gained it in the five o clock as the Spitfire appeared to reach the top of its climb. The Spitfire then immediately descended and appeared to make a pass over Waltham Abbey. He did not believe that there had been a NOTAM issued in the area. He assessed the risk of collision as Low. THE SPITFIRE PILOT declined to file a report. Factual Background The weather at Luton was recorded as: METAR EGGW Z 18007KT 140V SCT047 17/07 Q1003 1

39 Airprox Analysis and Investigation CAA ATSI The PA28 was routing to Stapleford and had been receiving a Basic Service from Luton Radar. However, at the time of the occurrence the PA28 had left the Luton frequency and was about to select the Stapleford frequency. Just prior to leaving the frequency, the Luton Controller had issued traffic information to the PA28 about an unknown contact ahead. The pilot had reported visual with the traffic and then changed frequency. Radar data showed an unknown aircraft operating in the vicinity at a fairly high speed and making tight turns. There was no height information but it was possible to identify the aircraft using the Mode S transponder data and confirm it was a Spitfire. After leaving the Luton frequency, the PA28 pilot observed the Spitfire fly at low-level and then commence a steep climb. The PA28 pilot took evasive action by descending and reported that the Spitfire few overhead by 500ft. Under Basic Service a controller is not required to provide any Traffic Information but if a controller considers there to be a definite risk of collision a warning may be issued to the pilot. Under a Basic Service a pilot is ultimately responsible for his own collision avoidance. Figure 1 showed the position at CPA (1405:34). UKAB Secretariat Figure 1 (1405:34) Airspace Utilisation Section confirmed that there was not a NOTAM issued for a flypast or display in that area on that day. Both pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 1. If the incident geometry is considered to be converging at CPA then the Spitfire pilot was required to give-way. 2 Summary An Airprox was reported on 4 th May at 1405 between a PA28 and a Spitfire. The PA28 pilot was receiving a Basic Service from Luton, who gave Traffic Information, prior to him changing to Stapleford s frequency. The PA28 pilot saw the Spitfire and took avoiding action. Unfortunately the Spitfire pilot declined to take part in the Airprox process and did not have Mode C information, so the height separation is not known. 1 SERA.3205 Proximity. 2 SERA.3210 Right-of-Way (c) (2) Converging. 2

40 Airprox PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the PA28 pilot, transcripts of the relevant RT frequencies, radar photographs/video recordings and reports from the appropriate ATC and operating authorities. The Board first discussed the actions of the PA28 pilot. They noted that he had received timely Traffic Information from the Luton controller, despite being only on a Basic Service, which had enabled him to see the Spitfire. It was clear that at first he was happy that it did not constitute a threat; however, whilst remaining visual, he then became concerned that the other pilot had not seen him and was now climbing towards him. The Board noted that he had taken avoiding action by descending rapidly. Turning to the Spitfire pilot, the Board expressed their grave disappointment that the pilot had chosen not to participate in the Airprox process; by not submitting a report he had denied the Board the opportunity to make more definitive assessments based on known facts, which, in turn, denied other pilots the opportunity to gain valuable lessons. The Board recalled that the same operator had been involved in a previous Airprox in which he had similarly refused to participate, and wondered whether this reflected his attitude flight safety. In the absence of any report from the pilot, the Board were unable to offer any explanation as to why the radar recordings showed the SSR transponder being deselected as the Spitfire manoeuvred in the vicinity of Waltham Abbey, and then appeared on again for its return to the airfield. The Board frequently reiterates to pilots that switching off a transponder both denies other pilots TCAS information, and controllers Traffic Information, thus leaving see-andavoid as the only barrier to collision avoidance. Notwithstanding, the Board surmised from his flight profile that the Spitfire pilot was probably visual with the PA28, but without his version of the events they could not be sure whether this was definitively the case, or whether it was just serendipity that his profile took him behind the PA28. When discussing the cause of the Airprox, the Board acknowledged that both pilots were entitled to be where they were, and so they spent some time deliberating whether this was simply a conflict in Class G or whether the Spitfire pilot should have kept clear of the PA28 by a larger margin. However, in the end, by a majority, they decided that the Spitfire pilot had flown close enough to cause the PA28 pilot concern. That said, because the PA28 pilot had been able to take timely avoiding action, the risk was determined to be Category C. PART C: ASSESSMENT OF CAUSE AND RISK Cause: The Spitfire pilot flew close enough to cause the PA28 pilot concern. Degree of Risk: C. 3

41 AIRPROX REPORT No Date: 3 May 2015 Time: 1612Z Position: 5146N 00038E Location: 12nm N Southend (Sunday) PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft RJ85 Met balloon? Operator CAT Unknown Airspace London TMA London TMA Class A A Rules IFR Service Radar Control None Provider London Altitude/FL FL100 Transponder A, C, S Reported Colours White Lighting Nav, strobes Conditions VMC Visibility 10nm Altitude/FL FL100 Heading 050 Speed 265kt ACAS/TAS TCAS II Alert Nil Separation Reported 100ft V/0m H Recorded NK THE RJ85 PILOT reports passing FL100 in the climb when his aircraft passed about 100ft directly below a white untethered met balloon. He stated that there was insufficient time to take avoiding action. He assessed the risk of collision as Medium. THE MET BALLOON: Extensive tracing action established that no met balloons were notified as being released in the area. This did not of course preclude releases by other operators which were un-notified. THE LONDON CONTROLLER reports the RJ85 pilot reported passing close to a balloon. Nothing was seen on radar. As the aircraft had already passed the balloon and it was not visible on radar no avoiding action could be given. Factual Background The weather at Southend was recorded as follows: EGMC G33KT 9999 FEW035 18/09 Q0997 Analysis and Investigation CAA ATSI The nearest met office site for launching balloons is at Shoeburyness, but these are only launched Monday to Friday the prevailing wind also would have taken such balloons to the east. 1

42 Airprox A further possibility is a site at Cardington but this is some 40 miles to the west and, although the wind was strong, it is unlikely any launch from this site would still be at 10000ft in this vicinity. There were no met balloon launch NOTAMs in this area. Summary An Airprox was reported when a RJ85 and a reported Met balloon flew into proximity at about 1612 on Sunday 3 rd May The RJ85 pilot was operating under IFR in VMC in receipt of a Radar Control Service from London Control. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of a report from the RJ85 pilot, radar photographs/video recordings, a report from the air traffic controller involved and a report from the appropriate ATC authority. Members noted that investigations had been unable to ascertain the release source of the reported met balloon, or indeed whether the reported object was a met balloon at all. In discussing the incident, it was noted that previous analysis had indicated that the stabilising altitude for a typical toy balloon was well below that reported by the RJ85 pilot and so it was unlikely to be a toy balloon. The Board were informed that there were commercial sources for weather balloon kits, which enabled balloon launches to high altitude, typically to the region of 100,000ft and even up to 145,000ft. These usually carried a small payload such as a camera or video recorder, with the total package amounting to a few kilograms in mass. It was also noted that CAA permission was required 28 days prior to launching such a high altitude balloon, and that this could be obtained from the CAA Airspace Utilisation Section 1. After further discussion the Board agreed that, whatever the type of balloon, the RJ85 pilot was clearly concerned by its proximity, but that, regrettably, the paucity of information meant that no meaningful assessment of risk was possible. PART C: ASSESSMENT OF CAUSE AND RISK Cause: The RJ85 pilot was concerned by the proximity of the balloon. Degree of Risk: D. 1 and contactable at ausops@caa.co.uk 2

43 Airprox AIRPROX REPORT No Date: 4 May 2015 Time: 1450Z Position: 5102N 00147W Location: Salisbury PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft PA28 PA28 Operator Civ Club Civ Club Airspace FIR FIR Class G G Rules VFR VFR Service Basic NK Provider Solent NK Altitude/FL 2200ft NK Transponder A NK Reported Colours Blue/white NK Lighting Anti collision HISL Anti - collision Conditions VMC VMC Visibility 20KM NK Altitude/FL 2200ft NK Altimeter QNH NK (1005hPa) Heading 080 NK Speed 105kt NK ACAS/TAS Not fitted NK Alert N/A NK Separation Reported 200ft V/0.5NM H NK Recorded NK V/NK H THE PA28 PILOT (AC1) reports flying straight-and-level on a VFR flight. Whilst heading 080 and at 2200ft he noticed another low-wing aircraft about 5-6 miles ahead. At that point he judged the aircraft would pass down his left side so took no action. He continued to monitor the other aircraft and, at approximately 1nm from his aircraft, the other aircraft turned sharply left in a descending turn, which put the aircraft on a course to pass across the front of his aircraft. He turned his aircraft left approximately 40, and the other aircraft passed down his right side. After passing his aircraft the other aircraft made another sharp turn to the right and resumed its original course. He assessed the risk of collision as Medium. THE PA28 PILOT (AC2) reports being in the area at the time of the Airprox and on a training flight, teaching stalling. He thinks the other aircrafts description fitted his lookout turns of 90 prior to a stall but he saw no other aircraft. He assessed the risk of collision as None. Factual Background The Southampton weather was recorded at the time as: METAR EGHI Z 24028G40KT 210V FEW027 BKN031 13/06 Q1000 1

44 Airprox Analysis and Investigation CAA ATSI The PA28 was in receipt of a Basic Service from Solent Radar at Southampton, and was squawking the assigned code of The pilot reported seeing the conflicting aircraft at a range of approximately 5-6 miles, and judged that it would pass down his left side. However, the other aircraft then made a sharp left turn which took it across the flight path of the P28 before it then turned back onto its initial course and passed down the right side of the P28. There was no mention of the Airprox at the time to Solent Radar. Radar recordings showed the P28 just prior to the occurrence at 1449:45 (Figure 1). This Figure 1 also showed another unidentified aircraft approximately 7 miles to the east which is potentially the other aircraft. Radar coverage at this height was poor in this area, and both these contacts disappeared from radar after this screen shot only to reappear at approximately 1453:00 (after CPA). It was therefore not possible to measure the minimum distance between the aircraft as neither aircraft were displayed at the time of passing. Figure 2 showed the position a 1453:36 after both aircraft had created a number of radar returns. It was not possible to identify the other aircraft. [UKAB Note: fortunately RAC were able to trace the aircraft subsequent to this report being compiled, although its pilot s report did not materially alter the ATSI analysis]. A controller providing a Basic Service is not required to monitor a flight. Under a Basic Service pilots are ultimately responsible for their own collision avoidance. Both the Radar screenshots depicted below show Old Sarum Airfield ( LS ) which is approximately 2 miles north of Salisbury. Figure 1 (Swanwick MRT at 1449:45) Figure 2 (Swanwick MRT at 1453:36) UKAB Secretariat Both pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard. 1 If the geometry of the incident was such that the aircraft were considered to be converging then both should alter course to the right. 2 Summary An Airprox was reported when two PA28 aircraft flew into proximity at 14:50 on 4 th May PA28 (1) pilot was flying VFR under a Basic Service from Solent radar and saw PA28 (2) ahead, which he turned to avoid. PA28(2) pilot was also flying VFR and conducting lookout turns prior to a stalling exercise but did not see PA28(1). The incident was not shown on NATS radars and so exact separation is not known. 1 SERA 3502 Proximity 2 SERA 3510 Right of Way 2

45 Airprox PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the pilots of both aircraft, radar photographs/video recordings and reports from the appropriate ATC and operating authorities. The Board first discussed the barriers that were available to prevent this incident and some members wondered whether the pilots could have made better use of ATC to provide a greater level of service given that they were both operating near to Boscombe Down. However, it was pointed out that this incident had occurred on a Bank Holiday when Boscombe Down LARS would not have been available. Because of this, the first aircraft was in receipt of only a Basic Service from Solent Radar, and was unlikely to have gained anything else at that altitude due to the degradation of Solent Radar s coverage due to the distance from the radar head; a controller member confirmed that radar coverage from Southampton is particularly poor in that area. Turning to lookout, the Board commended the PA28 (1) pilot for his lookout, and for maintaining good situational awareness on the other aircraft as they approached. Members thought it was simply unfortunate that PA28 (2) s pilot had decided to turn just as they approached each other, but noted that the pilot of PA28 (1) was ready to react, and did so, in a timely and effective manner. The fact that he had had to turn left rather than right was a matter of circumstance at the time resulting from their propinquity at the point the PA28(2) turned. The Board did not have access to the PA28(2) pilot s report at the time of assessment, but it was ironic that he reported that he was likely conducting lookout turns, and had not seen PA28(1) approaching from ahead. The fact that the report from the second aircraft involved was not received until just after the Board had sat was deemed by Director UKAB not to have affected their assessment of cause and degree of risk. The Board determined that the cause had been a simple conflict in Class G airspace that had been resolved by the PA28 (1) pilot. This was not a situation of a late sighting by PA28 (1) pilot (albeit it was subsequently discovered to be a non-sighting by the PA28 (2) pilot) but was simply a matter of him reacting to a conflict that did not arise until a late stage. Board members again commended the pilot of PA28 (1) for his alertness, situational awareness, and timely and effective avoiding action; they assessed the risk as Category C. PART C: ASSESSMENT OF CAUSE AND RISK Cause: A conflict in Class G airspace resolved by the PA28 (1) pilot. Degree of Risk: C. 3

46 AIRPROX REPORT No Date: 2 May 2015 Time: 1018Z Position: 5151N 00026E Location: 7.5nm ESE Stansted (Saturday) PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft Rotorway 162 Vans RV7 Operator Civ Pte Civ Pte Airspace London FIR London FIR Class G G Rules VFR VFR Service Basic None Provider Essex Radar N/A Altitude/FL No Mode C No Mode C Transponder A A, S Reported Colours Yellow/black Yellow Lighting Nav, strobe Strobe Conditions VMC VMC Visibility 25km >10nm Altitude/FL 1250ft ~1500ft Altimeter NK (1012hPa) QNH (NK hpa) Heading Speed 80kt 150kt ACAS/TAS Not fitted Not fitted Separation Reported 0ft V/50ft H Not Seen Recorded NK V/0.1nm H THE ROTORWAY PILOT reports transiting to a private site 2nm southeast of Stansted Airport. He was about to enter the CTR when a yellow, low-wing, single-engine aircraft passed in front of him from left to right, co-altitude and at a distance of about 50ft. The pilot stated that he did not have time to react to the other aircraft s presence. He assessed the risk of collision as High. THE RV7 PILOT reports transiting to Andrewsfield with Stansted on Box 2 and Andrewsfield on Box 1. Neither he nor his passenger saw another aircraft in close proximity. Factual Background The weather at Stansted was recorded as follows: METAR EGSS KT 9999 SCT021 09/04 Q1011 Analysis and Investigation CAA ATSI Not the subject Rotorway The helicopter pilot was in receipt of a Basic Service from Essex Radar. At 1016:20, he was issued a clearance to transit the Stansted CTR not above 1500ft VFR. Initially the routing was 1

47 Airprox under the Stansted CTA in Class G airspace, which is where the Airprox occurred. The RV7 pilot had called Essex radar at 1013:00, and was asked to standby and remain outside controlled airspace. No service was provided to him. The RT traffic loading throughout this period was high as the controller was engaged in providing Approach Radar Services to Stansted as well as accommodating various transit aircraft and other joining aircraft. There was no mention of the occurrence on RT at the time. Under a Basic Service pilots are ultimately responsible for the provision of collision avoidance and controllers are not expected to monitor individual flights 1. UKAB Secretariat The Rotorway and RV7 pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 2. The incident geometry was converging and the RV7 pilot was required to give way to the Rotorway 3. Summary An Airprox was reported when a Rotorway and an RV7 flew into proximity at 1018 on Saturday 2 nd May Both pilots were operating under VFR in VMC, the Rotorway pilot in receipt of a Basic Service from Essex Radar, and the RV7 pilot not in receipt of an Air Traffic Service. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the pilots of both aircraft, radar photographs/video recordings and a report from the appropriate ATC authority. The Board first considered the pilots actions. Members were given further information on the Rotorway pilot from one of the members who had spoken to him about the incident. He frequently flew this transit route and, on this occasion, had been looking to his right to gain visual contact with a Police helicopter whose position he had gleaned from RT traffic. The RV7 then passed in front of him with no time to react. As for the RV7 pilot, he had already called Essex Radar but was not able to obtain a Service due to controller workload. He was approaching his destination, and had selected both Stansted (Essex Radar) and Andrewsfield RT frequencies on his two radios. He reported that neither he nor his passenger, with a combined total of many thousands of flying hours, saw the helicopter. The Board noted that the Essex Radar controller was operating under a high workload and was not able to provide Traffic Information to the pilots, who were on converging tracks. Members wondered whether the attention of the RV7 pilot and his passenger had been directed at identifying Andrewsfield to the detriment of their general lookout, and agreed that the lack of visual sighting by both pilots of the other aircraft underlined both the frailty of human perception, and the overriding need to counter this by maintaining an effective lookout. Ultimately, members agreed that the Airprox had been caused both by the non-sighting by the RV7 pilot and, because his sighting was too late to allow effective avoiding action, the effective non-sighting by the Rotorway pilot. The Board emphasised that this assessment was not in criticism of the pilots but simply a statement of fact which underlined the importance of effective lookout, especially in Class G airspace. In assessing the risk of collision, the Board agreed that the unfortunate combination of a lack of Air Traffic Service, the limited provisions of a Basic Service, and both pilots lookout probably being directed away from the respective conflicting traffic, resulted in all barriers to mid-air collision, other than chance, being removed; the situation had only just stopped short of an actual collision. In the course of the discussion, members also noted that the RV7 pilot had not selected Mode C SSR. They re-iterated that selection of Mode C was an important factor in flight safety, both as an awareness tool for ATC for potential conflict avoidance, and to allow other aircrafts TCAS or TAS to 1 CAP774, paragraph SERA.3205 Proximity. 3 SERA.3210 Right-of-way (c) (2) Converging. 2

48 Airprox operate effectively if they were so fitted. As a result, members strongly encouraged all pilots routinely to select Mode C on. PART C: ASSESSMENT OF CAUSE AND RISK Cause: A non-sighting by the RV7 pilot and effectively a non-sighting by the Rotorway pilot. Degree of Risk: A. 3

49 Airprox AIRPROX REPORT No Date: 13 May 2015 Time: 1206Z Position: 5253N 00012E Location: 10nm N Norwich PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft EC155 Typhoon FGR4 Operator Civ Comm HQ Air (Ops) Airspace London FIR London FIR Class G G Rules IFR VFR Service Traffic Traffic Provider Norwich Swanwick Mil Altitude/FL FL19 Transponder A/C A/C Reported Colours Blue, red, white Grey Lighting HISL, navigation, landing Navigation, HISLs (white) Conditions VMC VMC Visibility >10km 20km Altitude/FL ~2000ft 2000ft Altimeter QNH (1015hPa) RPS (1014hPa) Heading 019 Speed 150kt 400kt ACAS/TAS TCAS I Not fitted Alert Unknown N/A Separation Reported 200ft V/0m H 200ft V/0m H Recorded 300ft V/<0.1nm H THE EUROCOPTER EC155 PILOT reports that he was in the cruise at approximately 2000ft at 145kt IAS when Norwich informed them that a pair of military fast-jets were manoeuvring in their 3 o clock at FL100 and had been observed operating down to ground level. As this information was being passed the first of the pair of Typhoons came through their 12 o clock at 2000ft at a range of approximately 5-7nm. They informed ATC that they were visual and requested an update on the second aircraft. As this request was passed to ATC, they also advised them that they would like to manoeuvre to become better visual with the other fast-jet. The aircraft was turned to the right by and the right-hand seat pilot observed a fast-jet, 0.5nm away, coming directly at them approximately 200ft lower. The second Typhoon passed directly underneath them and then started a rapid climb; at the same time, Norwich ATC advised them that this aircraft was at their level.. They then observed the Typhoons depart to the west; following this they resumed their outbound track. He assessed the risk of collision as Medium. THE TYPHOON FGR4 PILOT reports that Havoc 21 flight were operating as a pair, conducting offrange, high-angle strafe practice on the Norfolk coast by Mundesly. They were under a Traffic Service from Swanwick Military, with both aircraft squawking Mode 3C. At 1204:44 Traffic Information was passed to Havoc 21 flight. Traffic was called as "South 10nm tracking North at 2000ft, probably North Sea rotary traffic". The formation assessed this to be leaving the Norwich Aerodrome Traffic Zone. At 1207:14 Havoc 21 requested an update on the rotary traffic. Based on estimated speed and routing Havoc 21 expected the traffic now to be around 5nm south of the formation but at 1207:22 Swanwick Military replied with the rotary traffic now east, 5nm tracking north-east. At the same time, during the recovery from a simulated strafe attack, Havoc 22 s pilot gained visual contact with the previously called rotary traffic and took avoiding action. A bunt of the aircraft was carried out once visual contact was achieved, resulting in a pass below the helicopter. 1

50 Airprox He assessed that the helicopter passed 200ft above and in front of him. Once clear of the traffic, Swanwick Military was advised of the Airprox at 1207:37. When Havoc 21 requested an update on the traffic, it was already merging with Havoc 22; the call of "5nm east" related to Havoc 21's position. He perceived the severity of the incident as High. THE SWANWICK MIL EAST TAC RIGHT CONTROLLER reports that he was called in to replace the East Tac Right position, working TTN31 in AARA8, with Havoc 21 flight working the same frequency, conducting General Handling (GH) north of Norwich prior to their tanking slot on AARA8. Whilst Havoc 21 flight were operating in the block SFC-15000ft (on the Yarmouth RPS 1015hPa) 20nm north of Norwich, he observed an aircraft routing northbound from Norwich at low-level. Because the aircraft was squawking 7427, and was indicating 2000ft, he called the traffic to Havoc 21 flight. He believed the initial traffic call was made when the traffic was south by 10-15nm, and he stated that he believed the traffic to be a rotary outbound from Norwich for the rigs. At the time of the traffic call, Havoc 21 flight were indicating well above and the call was made to provide situational awareness to the pilots in the event of a descent being initiated. Almost immediately after calling the traffic Norwich radar called to request Traffic Information on Havoc 21 flight. He responded that they were a pair of Typhoons operating in the block from SFC-15000ft on the Yarmouth RPS 1015hPa. The Norwich controller then pointed out his traffic squawking 7427, advising that it was a rotary aircraft under a Traffic Service, flying IFR not above 3000ft. Havoc 21 flight then requested a traffic update. At the time, Havoc 21 was west of the traffic by approximately 3-4nm, heading west, with the 7427 having turned north-east bound. The traffic was called as such. At the same time, Havoc 22 was south-east of the 7427 traffic by 2nm indicating approximately ft. At the time, Havoc 22 passed north-west bound overhead the rotary aircraft. Havoc 22's Mode C dropped out. He called the traffic south 2nm indicating 2000ft, to which Havoc 22 s pilot replied "visual with the traffic". Mode C then reappeared at 1700ft. Norwich radar then called back to state that his traffic was filing an Airprox against the 2 Typhoons. As Havoc 21 flight were observed to be in the middle of a manoeuvre, he opted to wait to tell the pilots once their manoeuvre was complete. Havoc 21 s pilot then stated that Havoc 22 s pilot would be filing an Airprox and asked if any further information was required by Swanwick. All details were logged and the Supervisor was informed. Havoc 21 flight completed their sortie and proceeded to AARA8 without further incident. He perceived the severity of the incident as Medium. THE SWANWICK MIL SUPERVISOR reports that he was about to handover the Supervisor role to the oncoming Supervisor when East Tac Right called him over. He pointed out his traffic, Havoc 21 flight, and the Norwich helicopter traffic, and advised him of the occurrence. He had not observed the event so he noted down all the details and logged the occurrence in the log-book. Factual Background The Norwich weather was: EGSH Z 31006KT 270V SCT046 14/05 Q1019= Analysis and Investigation CAA ATSI The EC155 pilot had departed from Norwich on a local IFR detail to the north routing off-shore. He was in receipt of a Traffic Service from Norwich Radar in Class G airspace. The Typhoon was the second of two such aircraft operating VFR on an off-range exercise operating up to 15000ft. The Typhoon crews were both in receipt of a Traffic Service from Swanwick Mil. The Norwich controller observed the two fast-moving aircraft and initiated a request for Traffic Information from Swanwick Mil. Figure 1 shows the 2 Typhoons (codes 6063, 6064), and the EC155 (code 7427). 2

51 Airprox Figure 1 (1203:45) Reciprocal Traffic Information was passed to Swanwick Mil during this call. The Norwich controller then passed this Traffic Information to the EC155 pilot. Approximately one minute later, the controller noticed the Mode C level information drop off the label on the first Typhoon. He was just updating this Traffic Information to the EC155 pilot as the transmission crossed with him reporting the first Typhoon in sight. The controller then passed Traffic Information on the second Typhoon whose level information had also disappeared. Radar then indicates the second Typhoon had descended below the EC155 and passed from south to north, apparently under the EC155. The EC155 pilot then reported the second Typhoon in sight and indicated he would file a report. The EC155 was level at 2000ft, and the pilot reported that the Typhoon passed underneath by approximately 200ft. The controller provided timely and appropriate Traffic Information both to the EC155 pilot and on the telephone to the Swanwick (Mil) controller. A controller providing a Traffic Service is not required to achieve deconfliction minima, and the avoidance of other aircraft is the pilot s responsibility 1. Although Figure 2 shows the Typhoon approximately 0.2nm from the EC155 and indicated 800ft, it should be noted that, due to the radar update rate, the high speed of the Typhoon, and the high rate of descent of the Typhoon prior to the occurrence, the relative distance and height information may not be accurate. Figure 2 (1207:30) 1 CAP 493 (Manual of Air Traffic Services Part 1) Section 1, Chapter 12. 3

52 Airprox Military ATM The tape transcript between Swanwick Mil (SM), Norwich ATC and Havoc 21 flight is below: From To Speech Transcription Time SM Havoc 21 flt Havoc 21 flight traffic south, er, one zero miles tracking north 12:04:41 indicating 2000 believed to be er, rotary for the rigs. Havoc 21 SM Havoc Roger. 12:04:40 Norwich SM.er request TI, er 15 north Norwich 6063, :05:20 SM Norwich Yeah TAC Right s on, er, pair of Typhoons in the block surface to ah, feet on the Yarmouth Norwich SM Roger traffic copied my traffic is Traffic Service just in their vicinity, 7427 SM Norwich contact Norwich SM helicopter IFR not above 3000 feet. SM Norwich Copied thanks for the info Havoc 21 SM Swanwick Havoc, request an update on the rotary traffic please. 12:07:03 SM Havoc 21 flt Havoc 21 flight er roger, now east of you 5 miles er, tracking north 12:07:07 east bound er, 2000 feet er, informed that he s not above er 3000 feet IFR under Traffic Service. Havoc 21 Havoc [--] descent 12:07:20 SM Havoc 22 er Havoc 22 that previously called traffic ah, south of you 2 miles 12:07:35 tracking north east flight level, correction, 2000 feet er rotary Havoc 22 SM Havoc 22 is visual er, with traffic the heading east? 12:07:42 Havoc Havoc, flow north feet wet 12:07:48 Norwich SN Hello, Norwich, just for your information the erm, track I told you about the zero sorry the SM Norwich Yup Norwich SM He s gonna file an Airprox against the two Typhoons that just passed 200 feet above and below him. Havoc 21 SM Er we re reporting an Airprox er, between Havoc 22 and er, rotary 12:08:43 traffic at 12:08 SM Havoc 21 Havoc 21 roger we ve just had a call from Norwich to er state that the rotary will be filing as well. 12:08:51 Swanwick passed Traffic Information to Havoc at 1204:41 (Figure 1) as, Havoc 21 flight traffic south, er, one zero miles tracking north indicating 2000 believed to be er, rotary for the rigs. Figure 1: Traffic Information at 1204:41 (EC155 squawk 7427; Havoc ; Havoc ). 4

53 Airprox At 1306:33 (Figure 2), Havoc 21 had descended rapidly but the speed and horizontal separation had kept the aircraft clear of the EC155. Figure 2: Geometry at 1206:33. At 1207:03, Havoc Flt requested an update on the rotary traffic and Swanwick replied at 1207:07 (Figure 3) with, Havoc 21 flight er roger, now east of you 5 miles er, tracking north east bound er, 2000 feet er, informed that he s not above er 3000 feet IFR under Traffic Service. The radar replay shows the rotary at 2nm to the south-east of Havoc 21 and approximately 3nm to the northnorth-west of Havoc 22. Figure 3: Traffic Information at 1207:07. 5

54 Airprox At 1207:25 (Figure 4) the replay shows 1nm separation and the Typhoon indicating 1600ft above. Figure 4: Closing geometry at 1207:25. The CPA was estimated at 1207:29 (Figure 5) with 0.1nm and 300ft separation. Figure 5: CPA estimated at 1207:29. 6

55 Airprox At 1207:35 (Figure 6), Swanwick provided an update, er Havoc 22 that previously called traffic ah, south of you 2 miles tracking north east flight level, correction, 2000 feet er rotary. Figure 6: Updated Traffic Information at 1207:35. The Typhoon crew had chosen to operate in the area because a number of factors: favourable met conditions, it provided a distinct target, and it was part of a composite sortie in D323C. The crew were aware of the Helicopter Main Routes and had relied upon Swanwick for the passage of Traffic Information. Additionally, the sortie was booked into the Low Flying System, and was on CADS 2. Due to the height difference and geometry of the conflicting tracks, the rotary was not in scan coverage, and the pilot was not visual until approximately 200ft away. The pilot described a high cockpit workload, and recalled the Traffic Information at 10nm and 5nm separation; the lead pilot commented that the information was not accurate as Havoc 22 conflicted with the rotary. To elucidate, the pilot commented that the Traffic Information was insufficient because the formation had taken a predictable pattern and the information was passed in relation to the lead aircraft. The Swanwick Tac controller passed Traffic Information as south at 10nm (Figure 1) to the flight callsign and the rotary was on a bearing of 168 at 8.1nm. An update was requested approximately 30 seconds prior to CPA, and the information was again given to the flight callsign as east at 5nm, not above 3000 feet, IFR. The radar replay shows that the rotary was 2nm to the south-east of Havoc 21 and approximately 3nm to the north-north-east of Havoc 22 (Figure 3). An update was passed specifically to Havoc 22 approximately 5 seconds after CPA. The Traffic Information had been passed to the formation, despite their split, and not to individual elements until post-cpa. The Swanwick Tac controller had three aircraft on frequency in a medium-to-low environment. Both Airprox aircraft were in Class G airspace and information had been passed between Swanwick and Norwich, but no formal coordination had been agreed due to the tracks being under a Traffic Service. As per CAP774, the definition of a Traffic Service states that, the controller provides specific surveillance-derived traffic information to assist the pilot in avoiding other traffic. Furthermore, under the terms of a Traffic Service, the controller is not required to achieve deconfliction minima and the pilot is responsible for collision avoidance. 2 Centralised Aviation Data Service, a web based advisory system designed to highlight potential conflictions in planned routes. 7

56 Airprox Safe separation was lost between Havoc 22 and the rotary. In the absence of TCAS/CWS and radar contact, the pilot relied upon Traffic Information from Swanwick. This information placed the rotary 5nm to the east, not above 3000ft, and as the pilot of Havoc 22 considered that the rotary was separated laterally, he continued a descent through the last reported altitude. The controller had readily highlighted the lessons from the incident and the actions can be viewed in the context of the wide radar range-scale being used to view all elements under a service (estimated radar range as 75nm), an expectation that the Typhoons could generally acquire conflictors on radar, and that the rapid descent had allowed less time to assimilate the closing geometries. Although the crews had attempted to maintain a predictable pattern of strafing runs, the controller may have misjudged spatial information and aircraft projection. The normal barriers to an incident would be ACAS/TAS, radar-derived Traffic Information and the principle of see-and-avoid. The Typhoon did not have ACAS or TAS fitted and Traffic Information was a partially-absent barrier. See-and-avoid was the principal barrier remaining to prevent loss of safe separation; the Typhoon pilot had a late sighting with 200ft separation and the rotary pilot first became visual with the fast jet with 0.5nm separation. UKAB Secretariat The pilots involved shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 3. Because the geometry was considered to be overtaking then the pilot being overtaken had right of way and the other pilot was required to keep out of the way of the other aircraft by altering course to the right 4. HQ Air Command All aircraft involved in this incident were operating in Class G airspace under a Traffic Service from two different agencies. The Typhoon pilots were well aware of the proximity of the HMRs, the possibility of encountering rotary traffic, and had made the conscious decision to seek an ATS from Swanwick (Mil) rather than Norwich. The Typhoons were driven into operating in this area by a combination of favourable weather and avoidance areas along the north Norfolk coast. The Traffic Information provided to the Typhoon pilots was reasonably accurate but was not sufficiently detailed for the formation number 2 to realise that the helicopter s track directly affected his aircraft. It is unclear whether or not the EC155 pilot was aware of the extent of the vertical and lateral manoeuvring of the Typhoons and so he may not have been able to formulate an informed plan to avoid any possible conflict. Summary The Airprox occurred in Class G airspace; the EC155 pilot, outbound from Norwich was in receipt of a Traffic Service from Norwich and the Typhoon pilots were in receipt of a Traffic Service from Swanwick Mil. The Typhoon flight was General Handling in the vicinity of the EC155 pilot s track between surface and 15000ft. The Typhoon pilots were issued with Traffic Information when the EC155 was approximately 8nm south of them. Discussion took place between Norwich and Swanwick Mil but no coordination was agreed. The pilot of Havoc 21 requested and was issued with an update to the Traffic Information. However, the pilot of Havoc 22, who was on a conflicting track with the EC155, was not given updated information on its position relative to him until after the CPA. The pilot of the EC155 was issued with Traffic Information about the Typhoons. He first observed the second Typhoon 0.5nm away, coming directly at his helicopter approximately 200ft lower. PART B: SUMMARY OF THE BOARD S DISCUSSIONS 3 SERA.3205 Proximity. Rules of the Air SERA.3210 Right-of-Way (c) 3 Overtaking. Rules of the Air

57 Airprox Information available included reports from the pilots and controllers concerned, area radar and RTF recordings and reports from the appropriate ATC and operating authorities. The Board first discussed whether it had been a reasonable plan for the Typhoon pilots to have carried out their operational manoeuvres in an area adjacent to the entrance/exit points (at the Norfolk northern coast) of two Helicopter Main Routes (HMR). A Military Pilot member explained that, although the Typhoon crews had been aware of the HMRs and the possibility of the presence of an off-shore helicopter flight, they had been restricted for a number of reasons from operating elsewhere. He offered that there had been a number of avoidance areas further along the coast; the weather in other areas had not been suitable to their task; they had required to operate as close as possible to D323C; and that there had been a suitable target on the coast. This led to a protracted discussion amongst the Board members as to the suitability of this decision. Although recognising the constraints mentioned, many members thought that it had not been a sensible decision to plan to conduct the exercise against a target that was, for all intents and purposes, at the start/end of the HMR. They opined that the incident could have been prevented simply by choosing a target even only a few miles away rather than rely so heavily on Traffic Information from ATC to warn them about any helicopters in the area. Given their highly-dynamic manoeuvring, and the likely inaccuracy of any Traffic Information as a result, that the Typhoon pilots had then continued to conduct their exercise after receiving Traffic Information about the EC155 raised questions in many members minds as to the fine line in decision-making between abandoning the run or continuing. A military pilot member said that the Typhoon crews had no doubt used the Traffic Information issued by the controller to try and calculate whether they could complete another two runs before the EC155 was in their precise operating area. Based on the information they had (which was referenced to the lead Typhoon), the Typhoon pilots had calculated that the EC155 had been about 5nm south of them and had judged, incorrectly, that they would be able to carry out their two runs before it had reached their vicinity. Irrespective of the fine judgement of this situation, a Civil Controller member with experience of the Norwich operation added that at certain times of the day the HMRs can become very busy indeed with off-shore traffic, and he considered that it was not an ideal place for military fast-jet manoeuvres at any time, even though he agreed that they had been entitled to be there. Turning to the ATC aspects, a military controller member agreed that the initial Traffic Information that had been issued to the Typhoon flight could have been more usefully articulated and had not been wholly accurate. The EC155 had been reported as 10nm south of them when it was actually about 8nm away, although it was recognised that the controller was operating with a radar display showing a range of at least 75nm and this large scale could have explained the discrepancy. Notwithstanding, members noted that the Typhoon flight had been informed that the EC155 was tracking north at 2000ft (towards their operating area). The Board then noted that, just over 2 minutes after receiving the initial Traffic Information, Havoc flight had requested an update on the rotary traffic. Traffic Information had been issued to the flight as 5nm east, tracking north-east not above 3000ft. The military controller member agreed that this had not been an appropriate message because, at the time, the two Typhoons had been operating independently some distance apart; Havoc 21 had already passed ahead of the EC155. He commented that Traffic Information should have been issued directly to Havoc 22 s pilot, rather than the flight, because he had been on a conflicting track with the EC155; as it happened, Traffic Information referenced to him was only passed after CPA. Some Board members wondered whether Norwich ATC should have invited the EC155 pilot to turn right to take him away from the operating area of the Typhoons. A civil controller member and a civil helicopter pilot member commented that this was not a practical solution given the dynamics at play. The EC155 had been comparably much slower and less manoeuvrable than the Typhoons, and there had been no guarantee that the Typhoon crews would have stayed operating in the same part of airspace. The Board then discussed how the Airprox could have been prevented. A number of Board members thought that coordination should have taken place between the Norwich and Swanwick (Mil) controllers to separate the flights vertically. The EC155 was on a constant flight-path not above 3000ft, and some members reasoned that the solution would have been for the Typhoons to level off 9

58 Airprox ft above the helicopter s operating altitude. However, a military pilot member commented that this would probably not have allowed the Typhoon pilots to carry out their task, and there had probably been a requirement for them to descend to a level well below the EC155 s altitude during their recovery manoeuvre. As such, height coordination was probably not compatible with the Typhoon pilots task. The discussion on preventive strategies continued to ebb and flow with two main themes: the Typhoon pilots choice of operating location, and their decision to carry on with their exercise after they were informed that the EC155 was in their general operating area. In this latter respect, a military pilot member confirmed that the Typhoon flight operation had been booked into CADS, and members thought that it would have been be advantageous to both them and the helicopter pilot if the helicopter operating companies could also book their flights on CADS. The Board were informed that it was possible for these companies to have access to a CADS terminal to book their flights, and the HQ Air Command representative undertook to explore this option. The Board then discussed the cause of the Airprox. It was apparent to the Board, using the radar recordings available, that Havoc 22 s pilot was overtaking the EC155 at the time of the Airprox; consequently, he was required to keep out of its way. It was therefore decided that the cause of the Airprox had been that he had flown into conflict with the EC155. The Board noted that Havoc flight had been issued with Traffic Information about the EC155, but that this had not been updated specifically to Havoc 22 s pilot before CPA; the Board considered that this was a contributory factor. Finally, after considerable further discussion, it was decided that the Typhoon crew s choice of operating area adjacent to the HMR entrance/exit point was also a contributory factor. The Board then turned its attention to the risk. It was noted that the CPA did not show on the radar recording but that it had been estimated as 0.1nm horizontally and 300ft vertically. Although the EC155 pilot had been issued with Traffic Information about the Typhoon at a late stage, due to the differing performance of the two aircraft, the Board agreed that he had been unable to take any action to avoid it. For his part, the Typhoon pilot had made a late sighting of the EC155, and had reported that he had bunted to pass 200ft below the helicopter. A military pilot member commented that the Airprox had occurred during the recovery phase of the Typhoon s strafe profile. Although the pilot would have been descending at during his strafe attack, he would have been pulling out at the time of the Airprox which, although still a highly-dynamic situation, had allowed him to abandon his recovery manoeuvre and take avoiding action to reduce the risk of a collision. Notwithstanding his action, the Board considered that safety margins had been much reduced below the normal, and so it was agreed that the Airprox should be categorised as risk Category B. PART C: ASSESSMENT OF CAUSE AND RISK Cause: Contributory Factors: The Typhoon pilot flew into conflict with the EC The Swanwick Mil controller passed Traffic Information relative to the Typhoon formation leader, not to the No2. Degree of Risk: B. 2. The Typhoon pilots chose to operate adjacent to the HMR entrance/exit point. 10

59 AIRPROX REPORT No Date: 13 May 2015 Time: 1729Z Position: 5253N 00100W Location: IVO Nottingham PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft PA28 Microlight 1 Operator Civ Pte Unknown Airspace London FIR London FIR Class G G Rules VFR VFR Service None None Altitude/FL 1400ft ~1400ft Transponder A, C, S None Reported No Report Colours White/burgundy Lighting Nav, strobe, landing, beacon Conditions VMC Visibility >10km Altitude/FL 1300ft Altimeter QNH (1016hPa) Heading 310 Speed 110kt ACAS/TAS Not fitted Separation Reported 30ft V/20m H Recorded NK V/<0.1nm H 2 THE PA28 PILOT reports approaching Nottingham airfield, outside aerodrome operating hours, descending at 200ft/min passing 1400ft QNH (1016hPa). The pilot had switched from a Traffic Service provided by East Midlands Radar to Nottingham Radio. Whilst looking towards the airfield in the 10 o'clock position the passenger noticed approaching traffic in the 1-2 o'clock position, same height, opposite direction. The pilot took immediate avoiding action, turning to the left and pitching down away from the traffic. The PA28 pilot provided video footage of the encounter 3. He assessed the risk of collision as High. THE MICROLIGHT PILOT: Despite extensive tracing action, the microlight pilot could not be found. Factual Background The weather at East Midlands was recorded as follows: METAR EGNX Z 08008KT CAVOK 15/05 Q1017 Analysis and Investigation CAA ATSI The PA28 pilot was inbound to Nottingham under VFR. At 1726:10, the PA28 was shown 8.1nm southeast of Nottingham airport at FL023, displaying an East Midlands radar squawk of The 1 Identified as a flexwing microlight trike on cockpit video footage provided by the PA28 pilot. 2 The microlight radar track was subject to significant jitter and as such the assessment of horizontal separation has been taken from PA28 cockpit video footage. 3 The encounter occurs at about 1:08 on the clip at: 1

60 Airprox unknown microlight was shown as an area radar primary contact passing 4.3nm to the eastnortheast of Nottingham Airport on a southerly track, see Figure 1. Figure 1: Swanwick MRT at 1726:10 The two aircraft continued to converge and, at 1728:26, the PA28 was shown displaying the general conspicuity code 7000 with the unknown contact in the PA28 s 1 o clock at a range of 1.2nm, see Figure 2. Figure 2: Swanwick MRT at 1728:26 The PA28 pilot s written report indicated that he had changed frequency from East Midlands Radar to Nottingham Radio. The PA28 was inbound to Nottingham after the official aerodrome operational hours and Nottingham ATSU confirmed that the PA28 was a locally based aircraft. The Air/Ground frequency would not have been manned outside the official opening hours. At 1728:44, the distance between the two aircraft was 0.2nm and the PA28 was indicating 1500ft as shown in Figure 3. 2

61 Airprox Figure 3: Swanwick MRT at 1728:44 CPA occurred between radar updates at about 1728:46. At 1728:48, the two aircraft had passed abeam and the PA28 was indicating 1400ft, see Figure 4. Figure 4 Swanwick MRT at 1728:48 Neither pilot was in receipt of an Air Traffic Service and in Class G airspace pilots are responsible for their own collision avoidance. UKAB Secretariat The PA28 and microlight pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 4. The incident geometry was converging and the PA28 pilot was required to give way to the microlight 5. A screen grab of the situation close to CPA is shown below with the microlight highlighted to the right of the windscreen. 4 SERA.3205 Proximity. 5 SERA.3210 Right-of-way (c) (2) Converging. 3

62 Airprox Summary An Airprox was reported when a PA28 and a microlight flew into proximity at 1729 on Wednesday 13 th May The PA28 pilot was operating under VFR in VMC, not in receipt of an Air Traffic Service. The microlight pilot could not be traced. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of a report from the PA28 pilot, radar photographs/video recordings and a report from the appropriate ATC authority. Members quickly agreed that the PA28 pilot was required to give way to the microlight, but equally that one cannot give way to that which one does not see. The cockpit video showed that the microlight, initially below the PA28, contrasted poorly with the background terrain, further adding to difficulty in visual acquisition. In the event, it was the PA28 passenger who first saw the approaching microlight and alerted the PA28 pilot to its presence, who was then able to take avoiding action. Some members felt the PA28 pilot may have been concentrating on establishing visual contact with his destination airfield, ahead of him, and that the microlight pilot may have been heading into sun, with attendant difficulty seeing the PA28. Ultimately, the PA28 pilot saw the microlight at a very late stage and, although he took avoiding action, was only able to increase separation marginally. It appeared from the PA28 cockpit video that the microlight pilot did not take avoiding action, or took action after passing out of the camera field of view and hence so late as to be ineffective in increasing separation. Members agreed that this probably amounted to a non-sighting by the microlight pilot, or a sighting so late as to effectively be a non-sighting. After further discussion it was agreed that chance had played a major part in events, and that separation had been reduced to the minimum, only just stopping short of actual collision. Members also noted that the PA28 pilot had been in receipt of a Traffic Service with East Midlands Radar prior to switching to the Nottingham RTF. He called en-route if nothing further to affect about 1min prior to CPA, with area radar recording showing the microlight PSR track converging in his right 1 o clock at a range of 2.9nm. Members agreed that, ideally, Traffic Information on this track should have been passed to the PA28 pilot prior to him going en-route, but they were unable to ascertain whether the microlight track had appeared on the East Midlands radar console display. PART C: ASSESSMENT OF CAUSE AND RISK Cause: A late sighting by the PA28 pilot and a probable non-sighting by the microlight pilot. Degree of Risk: A. 4

63 AIRPROX REPORT No Date: 27 Apr 2015 Time: 1256Z Position: 5212N 00008W Location: 1.2nm NNW Gransden Lodge PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft LS4 Glider F4U Corsair Operator Civ Pte Civ Comm Airspace London FIR London FIR Class G G Rules VFR VFR Service None None Altitude/FL 3500ft No Mode C Transponder Not Fitted A Reported Colours White Blue/Yellow Lighting None NK Conditions VMC VMC Visibility 15km 50km Altitude/FL 3700ft 5000ft Altimeter QNH (NK hpa) NK Heading 220 Turning right Speed 55kt 230kt ACAS/TAS FLARM Not fitted Separation Reported 0ft V/200m H 100ft V/400m H Recorded NK V/0.1nm H THE LS4 PILOT reports having been winch launched from Gransden RW04 into a thermal to 3800ft. He exited the thermal 1.7km from Gransden hanger and turned left to fly parallel to RW 22, with the intention of making a left run over the clubhouse start turn point. In a visual scan to the right he observed the Corsair in a vertical climb about 200m off the starboard wing, with the aircraft underside toward the glider. The LS4 pilot was unsure of [the Corsair s] flight path, so he made a left turn away towards the airfield, and airbrake descended to land. The pilot reported that a club member had observed the Corsair flying close by at high speed when there were a number of gliders in the vicinity of the airfield. He had identified it as a Corsair and, the following day, spoke to the pilot, who acknowledged performing aerobatics in the vicinity of Gransden airfield but felt there was no risk to gliders. The LS4 pilot stated that he did not report the incident at the time since the Corsair pilot had been identified and spoken to. However, the week before filing this report there was another incident with a different aircraft performing aerobatics out of cloud and close to the airfield and so the club CFI felt it was important to record this event too. He assessed the risk of collision as Medium. THE CORSAIR PILOT reports that following a sustained period of heavy winter maintenance, a shakedown flight was planned with the requirement to remain as close to the home airfield as possible, in case of technical problems, whilst operating within a sensible height band of 3000ft to 6000ft. The area selected was adjacent to Bourn airfield. The weather was broken cumulus with large 'blue gaps between; outstanding conditions for gliding and therefore he was not surprised to see a number of gliders engaged in both local and cross-country flying during the flight in question. For this reason, he specifically avoided flying under developed clouds where gliders where likely to be thermalling, and remained in the 'blue' sections where gliders were less likely to be, and would hopefully stand out against the sky. At one point in the flight, whilst manoeuvring in a right tum, he saw a glider under the edge of a cloud also in a right tum. Vertical separation was about 100ft and he observed that there was no risk of collision. In order to maintain a reasonable lateral separation, he tightened the turn slightly to pass at an estimated lateral separation of 400m. The rest of the flight 1

64 Airprox was uneventful but, following landing, the aircraft operator received a call from a gliding club official at Gransden Lodge, who seemed somewhat disturbed that anybody else would consider operating near 'their patch', regardless of altitude. A lengthy conversation ensued, but at no point was it suggested that the incident required the filing of an Airprox, nor was the opportunity offered to speak directly to the glider pilot involved. He assessed the risk of collision as None. Factual Background The weather at Cambridge was recorded as follows: METAR EGSC Z VRB02KT 9999 SCT034 09/M01 Q1012 Analysis and Investigation UKAB Secretariat The LS4 and Corsair pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 1. If the incident geometry is considered as head-on or nearly so then both pilots were required to turn to the right 2. If the incident geometry is considered as converging, then the Corsair pilot was required to give way to the LS4 3. If the incident geometry is considered as overtaking, then the LS4 pilot had right of way and the Corsair pilot was required to keep out of the way of the LS4 by altering course to the right 4. Comments BGA Whilst it is very good to see such awareness of gliding operations, it is unfortunate that the Corsair pilot chose to conduct his test flight so close to a known and promulgated area of intense gliding activity. Summary An Airprox was reported when an LS4 glider and a Vought Corsair flew into proximity at 1256 on Monday 27 th April Both pilots were operating under VFR in VMC, neither in receipt of an Air Traffic Service. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the pilots of both aircraft, radar photographs/video recordings and a data log file. Members first considered each pilot s description of the Airprox itself. The LS4 pilot had observed the Corsair in a vertical climb about 200m off his right wing, with the aircraft underside toward him, whereas the Corsair pilot had seen a glider in a right turn. Members were also informed that the glider datalog file indicated that the glider was in a shallow left turn at CPA. After some discussion, members came to the conclusion that the Corsair pilot had probably either seen a different glider, or had seen the Airprox glider but not near CPA. Members commended the Corsair pilot for the degree of planning he had applied to the shakedown flight with respect to expected glider operations, but observed that he had nonetheless elected to operate in a promulgated area of intense gliding activity. 1 SERA.3205 Proximity. 2 SERA.3210 Right-of-way (c) (1) Approaching head-on. 3 SERA.3210 Right-of-way (c) (2) Converging. 4 SERA.3210 Right-of-way (c) (3) Overtaking. 2

65 Airprox Given that there were other areas in the immediate vicinity which were potentially available to the Corsair pilot, and which were not notified as areas of intense gliding activity, the Board felt that this was contributory to the Airprox. Notwithstanding, members also re-iterated that glider pilots are also required to share the available airspace with other entitled users, even if within an area notified as having intensive glider activity; a powered aircraft being operated in the vicinity of a glider site was not a cause for complaint in itself, unless other circumstances pertained. In the end, members agreed that the cause of this Airprox was that there had simply been a confliction in Class G airspace. They decided that the Corsair pilot had probably not seen the glider in question, and therefore felt that; as a result, in this instance safety margins had been much reduced below normal. PART C: ASSESSMENT OF CAUSE AND RISK Cause: A conflict in Class G. Contributory Factor: The Corsair pilot chose to conduct his shakedown flight in a promulgated area of intense gliding activity. Degree of Risk: B. 3

66 AIRPROX REPORT No Date: 26 May 2015 Time: 0927Z Position: 5236N 00028E Location: 6nm SW Marham PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft Tornado GR4 F15 x2 Operator HQ Air (Ops) Foreign Mil Airspace London FIR London FIR Class G G Rules VFR VFR Service Traffic Traffic Provider Marham Lakenheath Altitude/FL FL36 FL41 Transponder C/S C/S Reported Colours Grey Light grey Lighting HISL, nav Anti-collision Conditions VMC VMC Visibility 30km 10nm Altitude/FL 3500ft FL40 Altimeter QFE (1019hPa) Heading Speed 300kt 300kt ACAS/TAS TCAS II Not fitted Alert TA N/A Separation Reported 300ft V/500m H 500ft V/0.5nm H Recorded 500ft V/0.1nm H THE TORNADO PILOT reports that the crew were airborne from Marham at 0925, capped to climb to 5000ft initially to operate in the local area. The Navigator hooked a Link16 track north-west of Marham at 7000ft, noting it was an F-15, but did not recognise the track descending. Once airborne, the crew switched to Marham Zone on Stud 8 as briefed, requesting a Traffic Service. ATC did not respond to the first call on Stud 8, but answered the second call and confirmed the level as 5000ft. The Tornado was in a right-hand climbing turn through a gap in the clouds to remain VMC (cloud base 1800ft, tops 2500ft). Marham Zone then called "Traffic 1 o'clock, 3 miles... - The rest of the transmission was missed due to being stepped on by VHF guard, although FL40 was heard. As the Tornado passed through 3500ft he asked for a repeat of the message. At this point, the Navigator spotted a pair of F-15 aircraft conflicting with the Tornado flight-path, and called for the pilot to roll out and level off as the left-hand of the two F-15s passed overhead approximately 300ft above, heading in a southerly direction. The incident aircraft was fitted with Tornado Information Exchange Capability (TIEC) 1 and TCAS. The TCAS was selected to TA-only for the initial departure. On review of the aircraft tape, the TCAS 'Traffic' warning can be heard, although it is co-incident with the ATC call of 'Traffic' and was missed by the crew. The Link16 was selected to SILENT until approx 45sec after take-off, approx 40sec before the Airprox occurred. He assessed the risk of collision as Very High. THE F15 PILOT reports that the formation of 2 x F15s had just finished a task in East Anglia airspace. After General Handling was complete, they were passed from London Mil to Lakenheath Approach for their return to base. They were in a spread formation with Wardog 11 on the West side flying south towards Point Charlie. Upon contact with Lakenheath Approach they were cleared to 1 A data-link system. 1

67 Airprox descend to FL40. Due to weather at around 3000ft, he asked for a lower descent so they could make their way underneath the lower scattered deck and route to Point Charlie for a Charlie-to-Downwind procedure. Approach told them they were unable to descend further due to traffic of unknown altitude climbing out of RAF Marham. Wardog remained wings level at FL40, clear of weather and operating under a Traffic Service. At about that time, Wardog 11 and 12 both picked up visually an RAF Tornado in a climbing right-hand turn approximately 1nm away and 1000ft below their formation, climbing through a break in the clouds at their 10 o'clock position. The Tornado passed approx 500ft below and slightly aft of Wardog 11 flight. After passing, Wardog was cleared to descend to Point Charlie for a Charlie to-downwind and to contact Lakenheath Tower. He assessed the risk of collision as High. THE MARHAM ZONE CONTROLLER reports that he took over the Approach position with the Tornado pre-noted for departure north at FL50. Shortly after he took control, the Tornado crew got airborne and he initiated contact. Unfortunately, he made his initial call on Stud 4, and the crew was on Stud 8, so he immediately repeated the call on the correct frequency, applying a Traffic Service and included Traffic Information on a pair of F15's descending through the climb-out lane. The F15's were spotted initially in the Holbeach area at approximately FL120 heading south on an inbound profile to Lakenheath. Once the Tornado showed on radar, Lakenheath telephoned for Traffic Information and subsequent co-ordination. This call was answered by the Supervisor. The action agreed on the telephone was for the F15 crews to stop decent at FL50, and the Tornado crew to stop their climb at FL40. The stop-climb was passed to the Tornado crew twice, first on the initial call and a second time as the Tornado crew missed his first transmission due to another transmission on a different frequency. By the time they received the information, the tracks were approximately 3nm apart; however, the F15 crews had broken their agreed coordination and had descended to a similar level of the Tornado in a similar airspace. The Tornado crew called visual with the conflictor, took avoiding action, and briefly afterwards reported an Airprox on frequency. The Tornado crew left his frequency en-route without further incident. He perceived the severity of the incident as Medium. THE LAKENHEATH COORDINATOR TRAINEE reports that Wardog 11 flight was initially handed over to them at about 40nm north-west of Lakenheath. After completion of the handover and upon initial contact, the Approach controller descended Wardog 11 flight to FL40 because there was no traffic in his way at the time, and the pilot was requesting direct to point Charlie. At approximately 7nm north-east of Marham they saw an aircraft depart Marham southwest-bound and climbing fast. As the Coordinator trainee, he called Marham as soon as he noticed the conflict, when the departing aircraft was at about 1700ft. While he was on the line, the Approach controller issued all of the required traffic calls and, he believed, in a timely manner. He believed that there were three traffic calls. During the time the traffic was being issued to Wardog, the coordinator trainee was on the line with Marham Approach, getting coordination. The coordination was for Marham to cap their aircraft at FL40 while they capped Wardog 11 at FL50. He immediately let his Approach controller know, and he relayed the instruction to Wardog 11. At that time Wardog 11 was already at FL46 and still descending. After receiving the instruction to climb back up to FL50, Wardog 11 s pilot continued his decent through FL45 saying he had the aircraft in sight. He was told a second time to climb and maintain FL50 but still continued descending. He said the traffic was no factor and requested a further descent to 3000ft. The Approach controller waited until Wardog 11 flight was clear of Marham s MATZ and then descended its pilot into point Charlie. Factual Background The Marham weather was: METAR EGYM Z 34009KT 9999 SCT018 13/09 Q1022 WHT NOSIG= METAR EGYM Z 31008KT 9999 BKN022 14/09 Q1022 WHT BECMG SCT025 WHT= 2

68 Airprox Analysis and Investigation Military ATM The incident occurred 5nm south-west of RAF Marham between a Tornado GR4, under a Traffic Service with Marham Zone, and a pair of F15s under a Traffic Service with Lakenheath Approach. The Radar Analysis Cell captured the incident using the London QNH 1023hPa. The transcript below shows the RT between Marham Zone and the Tornado GR4 pilot: From To Speech Time Tornado Zone Marham radar (Tornado C/S) airborne passing twelve hundred feet 09:25:41 for a Traffic Service. Zone Tornado (Tornado C/S) Marham approach identified traffic service reduced 09:25:45 traffic right one o clock five miles crossing right left indicating flight level six zero descending pair. Tornado Zone Marham Radar (Tornado C/S) radio check. 09:25:52 Non Zone VHF Marham Good Morning (non-airprox C/S) request information 09:26:04 Airprox C/S service. Zone Tornado (Tornado C/S) Marham Talkdown correction Marham Zone identified 09:26:07 Flight level er climb flight level five zero Traffic Service reduced traffic right one o clock three miles crossing right left indicating flight level four five pair stop climb flight level four zero. Tornado Zone Er say that again for (Tornado C/S). 09:26:24 Zone Tornado (Tornado C/S) stop climb flight level four zero. 09:26:27 Tornado Zone (Tornado part C/S) 09:26:43 Tornado Zone Er (Tornado C/S) declaring an Airprox at this time and request er 09:26:45 say again. Zone Tornado (Tornado C/S) er disregard pair of F15s now clear. 09:26:52 Tornado Zone That s copied (Tornado C/S). 09:26:55 Tornado Zone (Tornado C/S) the pair of F15S were at err approximately three thousand eight hundred feet and we err had to err level off to avoid. 09:26:58 The transcript below is between Lakenheath Approach and the F15 formation: From To Speech Time LAK F15 (F15 C/S) roger, descend and maintain FL40, proceed direct Charlie, 09:25:01 copy ATIS. F15 LAK (F15 C/S) request down to 3000? 09:25:39 LAK F15 (F15 C/S) maintain FL40 for now, there is traffic um in Marham 09:25:43 airspace. LAK F15 (F15 C/S) traffic 11 o clock five miles altitude indicates flight, 09:25:59 correction, one thousand six hundred, appears to be west bound, type unknown. LAK F15 (F15 C/S) climb and maintain FL50 reference traffic in your 12 o clock, 09:26:19 2 miles, altitude indicates F15 LAK (F15 C/S) got traffic in sight. 09:26:28 LAK F15 (F15 C/S) roger, climb and maintain FL50. 09:26:34 F15 LAK (F15 C/S) traffic is no longer a factor, request down to :26:38 LAK F15 (F15 C/S) maintain FL40, expect lower when clear of the MATZ. 09:26:43 3

69 Airprox The transcript below is between Lakenheath and Marham ATC. From To Speech Time LKH MRH SUP Hey Lakenheath request traffic information three six four six code. 09:25:57 MRH SUP LKH Err he s climbing up to five err sorry flight level five zero. 09:26:00 LKH MRH SUP Flight level five zero. 09:26:04 LKH MRH SUP??? seven down to four err we ve kept him at err five and then kept yours at 09:26:07 four until past. MRH SUP LKH Say again sorry. 09:26:12 LKH MRH SUP Errr zero four two seven we kept him at err flight level five zero. 09:26:13 MRH SUP LKH OK we ll stop him at err flight level four zero against your traffic not 09:26:16 descending below five even though he s at flight level four five now. LKH MRH SUP {unreadable} now we re climbing back up. 09:26:22 MRH SUP LKH Ok co-ordinated thanks Marham. 09:26:24 MRH SUP MRM Stop him at four please mate. 09:26:27 Zone MRH SUP {unreadable} he s just given me co-ordination at not below five zero and he s 09:26:31 at four one. MRH SUP LKH Marham approach. 09:26:41 LKH MRH SUP Hey we climbed and he has traffic in sight. 09:26:42 At 0925:41, the Tornado crew called Marham airborne for a Traffic Service. Lakenheath capped the F15 pilot s descent to FL40 at 0925:43. Marham ATC replied to the Tornado crew on the incorrect frequency and the Tornado crew asked for a radio check at 0925:52. The outbound Tornado first appeared on radar at 0925:55 (Figure 1). At 0925:59, Lakenheath requested Traffic Information from Marham and, at 0925:59, Lakenheath called traffic to the F15 pilots as: left 11 o clock, 5nm, and 1600ft, westbound. Figure 1: Tornado first appearing on radar replay (Tornado squawk 3646; F15s 0427). At 0926:07 (Figure 2), Marham transmitted on the correct frequency to provide a Traffic Service, climbing to FL50, with Traffic Information passed as: 1 o clock, 3nm, crossing right to left, indicating FL45; the controller finished with a stop climb at FL40. At the same time, Lakenheath had offered an agreement of the F15s at FL50 and the Tornado at FL40. [UKAB Note: but this was not finally understood and agreed between the two controllers as formal coordination until 0926:24] 4

70 Airprox Figure 2: 0926:07: Traffic Information from Marham and height separation requested by Lakenheath. At 0926:19, Lakenheath instructed the F15 pilots to climb and maintain FL50 for traffic 12 o clock, 2nm, and indicating 3000ft. [UKAB Note: at this point, the F15 rate of descent indicates that they were already at approximately 4700ft and descending at about 2000fpm]. At 0926:24 (Figure 3), Marham had agreed co-ordination with Lakenheath, and the Tornado crew had asked for a repeat of the previous transmission. At 0926:27, Marham re-iterated the instruction for the Tornado crew to stop climb FL40 [UKAB Note: this was not acknowledged by the Tornado crew until 0926:43, which was after CPA]. At 0926:28, the F15 pilots had called visual with the Tornados [UKAB Note: this was 9sec before CPA]. Figure 3: Geometry at 0926:24. At 0926:31, the Marham Supervisor commented that co-ordination had been at FL50 but the F15s were indicating FL41. At 0926:34 (Figure 4), Lakenheath reiterated the climb and maintain FL50 to the F15 pilots. Figure 4: Geometry at 0926:34 5

71 Airprox The CPA was estimated at 0926:37 (Figure 5) with 500ft and 0.1nm separation. At 0926:38, the F15 pilots stated that the traffic was not a factor and they requested a descent to 3000ft. Figure 5: CPA estimated at 0926:37. The relative positions of the RAF Marham and RAF Lakenheath MATZs are at Figure 6, both with runway configuration of 06/24. Figure 6: Positions of Marham and Lakenheath MATZs. The Tornado crew had established contact with the F15s on (TIEC) and TCAS; the F15s were detected 10nm to the north at 7000ft and the crew assumed that the FL50 departure clearance was to coordinate. No coordination had been agreed at this point. The Tornado crew did not get a reply from ATC on initial call, and they turned right to find a gap in the cloud. At the time, there was a lot of radio traffic on Guard, and the crew assimilated the Traffic Information at 3nm but did not assimilate the stop climb at FL40. A post-flight review discovered the TCAS TA, co-incidental with other radio traffic. Both crew members were searching for the F15s and Guard was deselected. The F15s were then spotted, the closest of which was on a confliction path. The navigator instructed the pilot to roll out and level off as the F15 passed 300ft overhead. The Marham controller was covering Approach, Director and Zone frequencies due to manpower limitations; the workload was low with one aircraft on frequency and one free-calling. ATC believed that FL50 was the aircrew requested level for departure and the unit investigation was not able to find the reason behind the FL50 departure profile. The controller had selected the incorrect frequency when the Tornado crew checked-in, and this led to a delay in providing a service and passing Traffic Information. Due to the delay, there was a compressed timescale to get the information to the Tornado crew. The call from Lakenheath on traffic in Class G, above the MATZ, was considered a courtesy call. As the coordination was finally agreed, the Marham controller had noticed that the F15s were already below the agreed level. The controller queried the situation with Lakenheath and provided the stop climb to the Tornado at FL40, which was not acknowledged; the controller did not get a readback. 6

72 Airprox The respective controllers passed Traffic Information, as per the provision of a Traffic Service, with Lakenheath passing accurate information at 5nm and 2nm. Marham ATC had attempted to call traffic at 5nm on initial climb-out call but, due to a frequency selection error, the information was passed at 3nm. Lakenheath initiated a call to Marham with 5.8nm horizontal separation and the agreement for height coordination was agreed with 3.9nm separation. As Lakenheath passed the instruction for the F15 pilots to climb and maintain FL50, the aircraft were 2.9nm apart with the F15s at FL46 in the descent. Two climb restrictions were passed by Marham ATC to the Tornado crew but that information was not assimilated possibly due to radio traffic and information overload; as the controller had missed the first call, a lot of information had to be passed to the crew, including type of service, a climb to FL50, reduction in service, Traffic Information and a stop climb at FL40 instruction. The abundance of information to the Tornado crew coincided with other visual/aural sources of information in the cockpit. No readback was obtained by the Marham controller. Lakenheath had shown good practice by attempting to pass information and coordinating, but the time scales left little time for an agreement and for gaining crew approval. [UKAB Note: Lakenheath attempted this coordination 2sec after observing the Tornado aircraft as they appeared on radar departing Marham]. The normal barriers to loss of safe separation would be ACAS, radar-derived Traffic Information, Deconfliction procedures and see-and-avoid. The F15s did not have ACAS but the Tornado crew had information from TIEC and TCAS. Traffic information was passed to both crews, and there appears to be an overload of information to the Tornado crew, which would normally lead to an increase in crew workload. Although the crews were in Class G airspace, more robust local procedures would assist Marham and Lakenheath deconflict their traffic. See-and-avoid was exacerbated by the cloud level and the need for both crews to find suitable gaps to remain VMC; the conditions help explain the F15 pilots actions to pass below FL50 and look for further descent. The sequence of events had become compressed and, despite best intentions, coordination had been agreed that was difficult to achieve in the time scales. Marham now provide departure instructions that keep Tornados in the MATZ (runway track to 2500ft) until twoway with Approach; this procedure allows a radar controller to act upon conflicting tracks and affords the protection of the MATZ. UKAB Secretariat Both the Tornado and the F15 crews shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 2. Initially the aircraft were on converging tracks; because the F15s were to the right of the Tornado, the latter s crew were required to give way 3. Subsequently, because the geometry changed to head-on after the Tornado turned, both the crews were required to avoid each other by turning to the right 4. CAP (The UK Flight Information Services) states; A Traffic Service is a surveillance based ATS, where in addition to the provisions of a Basic Service, the controller provides specific surveillance-derived traffic information to assist the pilot in avoiding other traffic. Controllers may provide headings and/or levels for the purposes of positioning and/or sequencing; however, the controller is not required to achieve deconfliction minima, and the avoidance of other traffic is ultimately the pilot s responsibility. CAP (Radiotelephony Manual) states: Messages should not contain more than three specific phrases, comprising a clearance, instruction or pertinent information. 2 SERA.3205 Proximity. Rules of the Air SERA 3210 Right-of-Way (c) (2) Converging. Rules of the Air SERA Right-of-Way (c) (1) Converging. Rules of the Air Chapter 3, Paragraph Chapter 2, Paragraph Transmitting Techniques 7

73 Airprox Comments HQ Air Command The investigation into this incident found that a number of compounding factors ultimately led to a late sighting of the F-15s by the Tornado crew. Many of the shortfalls identified have already been addressed, such as improved coordination between Lakenheath and Marham controllers and a revised VFR departure procedure from Marham. This incident does highlight the importance of clear and timely communication between all agencies involved in aviation and that assumption (such as that exhibited by the Tornado crew when issued an unexplained climb out restriction to FL50) often leads to an inaccurate mental model being formulated and a concomitant increased likelihood of the introduction of a Human Factors aspect Situation Awareness (SA) is only shared SA if all parties have the same understanding of the same situation. USAFE This Airprox illustrates the difficulty that controllers can experience in making effective coordination agreements with aircraft in receipt of a Traffic Service. That said, anticipation of coordination requirements can resolve most situations but in this incident only 56 seconds elapsed between the Tornado pilot s first call to Marham Approach and the CPA. Marham s amendment to its departure instructions is one step in the prevention of a similar occurrence in the future; a review of procedures and/or profiles where there is interaction between the Lakenheath RAPCON and Marham ATC will be another. Summary The Airprox occurred in Class G airspace south-west of Marham; both the Tornado and F15 crews were VFR and being provided with Traffic Services by Marham and Lakenheath respectively. The Tornado crew were routeing to the south-west from Marham and climbing to FL50. Very soon after the Tornado appeared on radar, Lakenheath instigated coordination with Marham against the F15s, which was eventually agreed as the Tornado to level at FL40 and the F15s to stop descent at FL50. The Marham controller issued Traffic Information to the Tornado crew about the F15s at 1 o clock 3nm and, in the same call, the crew were instructed to level at FL40; they did not assimilate this level instruction. Meanwhile the F15s had already descended through FL50 before Lakenheath were able to instruct them to stop their descent at FL50. Traffic Information was issued to them about the Tornado, the F15 crews reported visual, and, although being instructed to climb back to FL50, were happy to continue descent. The Tornado crew became visual with the F15s, rolled out and levelled off. The Tornado s TCAS had activated with a TA but this warning was not assimilated. The Tornado passed 500ft below the F15s. PART B: SUMMARY OF THE BOARD S DISCUSSIONS Information available included reports from the pilots and controllers concerned, area radar and RTF recordings and reports from the appropriate ATC and operating authorities. The Board first discussed the actions of the Marham Zone controller. The Board considered that it had been unfortunate that the controller had selected an incorrect frequency when the Tornado pilot had checked-in, and noted that he was covering Zone, Approach and Director at the time due to manpower limitations. His need to make a second transmission on the correct frequency had then resulted in him having to pass a longer and more complex than normal message to the pilot once two-way communication had been established. It was noted that this transmission had not only included information on the ATC service being provided, but had also included Traffic Information and changes to the cleared level. A military controller member considered that it would have been preferable to have restricted the call to just issuing the Traffic Information; the rest of the message could have been made in a subsequent transmission. The Board also noted that the Tornado pilot reported hearing the Traffic Information, and a mention of FL40, but did not hear the full message because it had been stepped on by a transmission on another frequency. Some members wondered 8

74 Airprox whether the Marham controller should have coordinated the Tornado s departure with Lakenheath prior to it getting airborne. However, military controllers informed the Board that, because the Tornado was on a VFR departure, there had been no requirement for the Aerodrome controller to have requested a departure release from the Zone controller. Consequently, the Zone controller would not have been aware of its departure until either it appeared on his radar display or the pilot contacted him. The Board noted that Lakenheath had contacted the Marham Supervisor as soon as they had seen the Tornado appear on their radar, and had attempted to agree coordination for the Tornado to maintain FL40 and the F15s FL50. Military Controller members agreed that this coordination should not have been agreed because it had not been achievable. By the time agreement had been reached, the aircraft had been only about 3nm apart; additionally, the F15s had already passed FL50 and were at FL45 descending. The Board opined that there had been no possibility for either ATC unit to have contacted and obtained an agreement from their respective pilots to carry out the action required in time. Some members recalled that there had previously been a Letter of Agreement (LOA) between Marham and Lakenheath establishing a coordination procedure to allow the mutual separation of their arrivals and departures; however, military controller members informed the Board that there was no LOA between the units in existence at the moment. As a result, the Board resolved to recommend that, Marham and Lakenheath review their coordination procedures with regard to simultaneous aircraft recovery and departure. The Board then discussed the actions of the Tornado pilot. In view of the weather some Board members wondered whether it was wise to have departed VFR. It was pointed out by military controller members that Tornado crews regularly depart VFR as a standard procedure, and it would have been the pilot s decision whether to change to an IFR departure in view of the reported weather. The Board then noted that the Tornado was equipped with TCAS and TIEC, but they were surprised that the TCAS had been selected to TA-only. A military pilot member explained that there were various times when it was necessary for military aircraft to switch their TCAS to TA only in order to avoid nuisance TCAS RAs during tactical manoeuvring (e.g. when pilots were carrying out operations where, by necessity, aircraft would be approaching close to each other visually whilst both squawking). He suggested that because Tornados had only recently been fitted with TCAS, the crews had still been discovering the best way to operate it. In his opinion this action had not affected the incident; the crew had information about the F15s from TIEC and TCAS, and Traffic Information had been issued by ATC. Other Board members disagreed, and still considered that, given that the Tornado was operating as a singleton, it would have been appropriate to have had the TCAS fully selected in order to gain maximum benefit. It was understood that Tornado TCAS selection was being reviewed; this information heartened the Board and they recognised that the incident had occurred when Tornado TCAS SOPs were in a process of development. Ultimately, when discussing further the Tornado crews actions, the Board opined that they had become aware of the F15s on TIEC/TCAS 7 soon after departure (when the F15s had been 10nm to the north and at 7000ft) and, in conducting a VFR departure, were responsible for avoiding conflict with them irrespective of any assistance or Traffic Information they might have received from ATC. Notwithstanding, the Board agreed that their incorrect assumption that the departure cap of FL50 had been imposed to afford them coordination had led them to proceed towards the F15s. The old adage of never assume, check was a relevant reminder to all in this respect. The Board then turned its attention to the actions of the F15 pilots. They had been carrying out ATC instructions to descend to FL40, and to route close to the Marham climb-out lane. By the time ATC had instructed them to maintain FL50 they had already passed that level. The Board noted that Lakenheath had then instructed them to climb back to FL50 as coordinated with Marham. However, because they had visual contact with the Tornado, the F15 lead had decided to continue descent to FL40. Some Board members were concerned about this action. Although on this occasion the crews had seen the correct aircraft, it was opined that there was always the possibility that the traffic being avoided was not the one that had been visually acquired. Other members thought that the F15 pilot would have had a reasonable expectation that the Tornado was indeed the aircraft on which he had 7 TIEC does not show level information. 9

75 Airprox received Traffic Information given that it matched exactly the call he had been given, and that no other aircraft had been called by ATC; they felt that his decision was rational as a result. Notwithstanding, all members agreed that it had been a fine line between him complying with the ATC instruction to climb back up to FL50 and his decision to continue descent contrary to their instructions. Finally, the Board wondered whether the chosen VFR recovery was a wise decision given the weather and the fact that they were descending through what they must have known was the Marham climb-out lane. However, the Board also noted that the F15 pilot had seen the Tornado some 9sec before CPA, which gave an indication as to the actual weather conditions he was operating within as he descended, and that this would also have influenced his decision as to the suitability of his routing. The Board then carried out a very lengthy discussion to ascertain what actions had actually caused this Airprox. Some members believed that the Marham Zone controller s initial use of the incorrect frequency, followed by an elongated message, had led to the Tornado crew not understanding the traffic situation and that this had then led to the Airprox. Other members considered that the ineffective coordination between Lakenheath and Marham, which was late and not achievable, had resulted in the Airprox occurring. However, these issues, together with the Tornado crew not assimilating their TCAS information, were finally considered to be contributory factors. Although not a unanimous decision the Board decided by a majority that it had been the decision by the Tornado crew to depart under VFR in broken cloud conditions that had led them to fly into conflict with the F15s, which they had been given Traffic Information on but saw only at a late stage. The Board then turned its attention to the risk. Although the agreed coordination between Lakenheath and Marham had not been achieved, the Board agreed that the F15 crews had been able to keep visual contact with the Tornado after sighting it approximately 1nm and 9sec away. Additionally, the Board noted that the Tornado crew had in the end sighted the F15s, albeit at a late stage, allowing the pilot to take avoiding action to pass about 500ft below them. Because timely and effective action had been taken to prevent the aircraft colliding, it was agreed that the Airprox should be categorised as risk Category C. PART C: ASSESSMENT OF CAUSE AND RISK Cause: Contributory Factors: The Tornado pilot chose to depart under VFR in broken cloud and flew into conflict with the F15s. 1. An incorrect initial frequency selection by the Marham controller. Degree of Risk: C. 2. A non-standard and overly complex RT call to the Tornado crew. 3. The Tornado crew did not assimilate their TCAS information. 4. The agreed Lakenheath/Marham coordination was ineffective and unachievable. Recommendation: Marham and Lakenheath review their coordination procedures with regard to simultaneous aircraft recovery and departure. 10

76 Airprox AIRPROX REPORT No Date: 30 May 2015 (Saturday) Time: 1355Z Position: 5122N 00120W Location: Kingsclere PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft Cirrus 75B Light Aircraft Glider Operator Civ Pte Unknown Airspace Lon FIR Lon FIR Class G G Rules VFR NK Service None NK Provider N/A NK Altitude/FL NK Transponder Not fitted A,C Reported Colours White/Red White Lighting N/R NK Conditions VMC NK Visibility >20km NK Altitude/FL 3400ft NK Altimeter QFE (987hPa) NK Heading 315 NK Speed 50kt NK ACAS/TAS Not fitted NK Separation Reported 20ft V/150ft H Recorded NK THE CIRRUS PILOT reports cruising between thermals on a bearing towards Newbury when he noticed an aircraft 90 to his right and slightly lower, the aircraft was single engine, low-wing, white and he could see the pilot was wearing a red top. He was unable to take avoiding action right as this would have taken him towards to other aircraft, to turn left would have meant losing sight of it, and to dive would have taken him through its level, so he kept the control stick slightly back and hoped the other aircraft would continue straight-and-level and that he did not encounter any sink. He did not get the registration because he was intent on looking at the pilot in the other cockpit to see whether he was looking at him and hoping to get an acknowledgement, which he didn t get. He perceived the severity of the incident as High. THE LIGHT AIRCRAFT PILOT could not be traced. Factual Background The weather at Odiham was recorded as: METAR EGVO Z 24011KT 9999 SCT045 SCT250 15/04 Q1014 BLU Analysis and Investigation UKAB Secretariat The incident was difficult to confirm with any degree of certainty on the NATS radars, because the glider was not transponding and the primary contact was intermittent. Therefore, tracing pilot two proved to be impossible. 1

77 Airprox Both pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 1. When two aircraft are converging at approximately the same level, the aircraft that has the other on its right shall give way, except as follows: (i) power-driven heavier-than-air aircraft shall give way to sailplanes... 2 Comments BGA There was very little that the glider pilot could do in the circumstances, although this Airprox does demonstrate that good look-out is essential. Summary An Airprox was reported on 30 May at 1355 between a Cirrus Glider and an untraced light aircraft. The Glider was not receiving an ATS, nor did he have any TAS equipment, therefore he did not receive any Traffic Information. Unfortunately the pilot of aircraft 2 could not be traced. PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the glider pilot, radar photographs/video recordings, reports from the air traffic controllers involved and reports from the appropriate ATC and operating authorities. The Board noted that both aircraft were operating in Class G airspace, both were entitled to be there, and that the primary barrier to preventing a mid-air collision was see-and-avoid. As such, it was vital that both pilots employed good look-out techniques. The Board commented that it was unfortunate that the incident did not show on the NATS radars, and so the pilot of the light aircraft could not be traced to provide his version of events. Nevertheless, recognising that the light aircraft pilot was required under SERA to give way, and because he had not reacted to the glider, the Board thought it likely, from the glider pilot s description of the events, that he had not seen the glider. The Board acknowledged that it was the glider pilot s look-out that enabled him to detect the conflict; albeit too late to take more positive avoiding action to ensure that the separation was more than the bare minimum. This led the Board to determine the cause of the Airprox as a late sighting by the Cirrus pilot and probably a non-sighting by the light aircraft pilot. Even without radar analysis it was clear from the glider pilot s report that there was nothing that he could do to improve matters, and so the risk was assessed as Category A, separation had been reduced to the minimum and chance had played a major part in events. PART C: ASSESSMENT OF CAUSE AND RISK Cause: A late sighting by the Cirrus pilot and probably a non-sighting by the light aircraft pilot. Degree of Risk: A. 1 SERA.3205 Proximity. 2 SERA.3210 Right-of-way. 2

78 Airprox AIRPROX REPORT No Date: 29 May 2015 Time: 1230Z Position: 5404N 00108W Location: 4nm NE Linton on Ouse PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft 2 xtucano Tucano Operator HQ Air (Trg) HQ Air (Trg) Airspace N Yorks AIAA N Yorks AIAA Class G G Rules VFR IFR Service Traffic Traffic Provider Linton Linton Altitude/FL FL61 FL52 Transponder A,C,S A,C,S Reported Colours Black/Yellow Black/Yellow Lighting Strobes, Nav, landing lights. Strobes, Nav, landing lights. Conditions VMC VMC Visibility 15km >10km Altitude/FL 5700ft NK Altimeter QFE 1013hPa (1000hPa) Heading Speed 180kt 150kt ACAS/TAS TCAS I TCAS I Alert TA TA Separation Reported 1200ft V/0.5nm H 1000ftV/2nm H Recorded 900ft V/0.7nm H THE TUCANO FORMATION PILOT reports he was the lead of a formation of two Tucanos. They were receiving a Traffic Service from Linton Zone for a cloud break. The cloud was broken layers with reasonable gaps in between, within which the visibility was good. Descent was commenced at 7500ft, approximately 6nm from Linton. An initial clearance to 4000ft was given by the Zone controller. On approaching 6000ft, both aircraft received a TCAS TA, indicating traffic was moving left-to-right in the 1 o clock position at 4500ft. No Traffic Information had been passed by the controller. The formation stopped descent at 5700ft and the controller was informed. The conflicting traffic was seen first at 0.75nm, reducing as it passed left-to-right beneath the formation. He considered that, had it not been for the situational awareness given by the TCAS, a high risk of collision was likely. He perceived the severity of the incident as Medium. THE TUCANO (B) PILOT reports that he was asked to submit his report 11 days after the event and therefore his recollection was sketchy as it was not a particularly memorable event. He was on an instructional sortie to teach TACAN holds and ILS approaches. On departing Linton they had been cleared own navigation for the TACAN hold, climbing to FL50. There were good breaks in the cumulus cloud so they were under a Traffic Service. As they approached the 069 radial (the correct outbound radial for the initial approach fix) they received Traffic Information on a pair of Tucanos, in the 1 o clock position, above, but descending. These corresponded with traffic seen on the TCAS. The student and instructor continued to monitor the TCAS vertical separation, whilst also looking out for the traffic. A few seconds later they received a TCAS TA as the contact continued to descend towards them, but almost immediately the student spotted the pair of Tucanos, 1000ft above in the 2 1

79 Airprox o clock position. Avoiding action wasn t necessary, but the student elected to ease a few degrees to the left to aid separation (although the instructor believed that even without this, they still would have passed behind). As he did so, the Tucanos appeared from behind the canopy arch and instructor also became visual. He couldn t recall how close the traffic passed, but remembered not being concerned by their proximity. The pair passed behind and his student continued to the TACAN hold. He assessed the risk of collision as Low. THE LINTON ZONE CONTROLLER reports that the formation called approximately 8nm east of Linton at 7000ft, with the intention of descending to low-level to the west of Linton. They had requested a Traffic Service and so the controller gave a squawk and indentified them. The instruction to set QFE 1000hPa was given in preparation for the subsequent descent. RW28RH was in use at the time, so he immediately called the Tower controller to place a climb-out restriction of 3000ft QFE, with the intention that this would allow the formation to initially descend to 4000ft. The controller leaned across to the Departures controller to inform him that a climb-out restriction was in place, and pointed out the formation to the east. He then called the Approach controller and informed him of the MATZ overflight, gave traffic information on the formation, and advised that there would be a climbout restriction of 3000ft in place until his aircraft were well clear to the west. During this time he received a call from Dishforth Tower wanting to pre-note a Dishforth departure, but he told them to stand-by. The formation then asked whether they had traffic south-west of their current position, he called the traffic, which was about 3nm north-east of Linton, which he now believes was above the 3000ft climb-out restriction. The formation self-imposed a stop descent of 5700ft, and informed the controller that they would be filing an Airprox as he had cleared them to a height below that of conflicting traffic. Once clear of the traffic they continued the descent and went en-route. The controller noted that he believed that all aircraft climbing out would be not above 3000ft QFE, and was not made aware of any conflicting traffic which was already above that height. He perceived the severity of the incident as Medium. THE LINTON APPROACH CONTROLLER did not file a report. THE LINTON SUPERVISOR reports that traffic levels on the unit were very low. Ironically he was taking a telephone call from CFS Cranwell regarding circuit integration at the time of the incident, he was therefore at his workstation taking notes on the telephone call when he looked up and noticed two aircraft transiting towards each other at different levels - the westerly one climbing and the easterly descending, although he recalls that there was at least 1500ft between them at the time. He stood up to ensure the Zone controller was aware of the traffic, but as he did so the Departures controller also stood up blocking his way. He pushed across the departures controller and, because the Zone controller was transmitting, pointed to the traffic that he was concerned about. The controller acknowledged his actions, and so the Supervisor went back to his workstation and observed both aircraft turning away. The Zone controller subsequently explained that the Tucano formation would be filing an Airprox. Factual Background The weather at Linton was recorded as: METAR EGXU Z 36004KT 9999 SCT015 10/06 Q1002 WHT TEMPO 29016G26KT FEW020 BLU Analysis and Investigation Military ATM The Airprox occurred on 29 May 15 at 1230, 4nm NE of RAF Linton-On-Ouse between a single Tucano under a Traffic Service with Linton Approach and a pair of Tucanos (callsign Cordite) under a Traffic Service with Linton Zone. 2

80 Airprox Portions of the transcript between Linton Approach and Tucano (B) is below: From To Speech Transcription Time Tuc APP Linton Director, {Tucano c/s} airborne passing 1000ft climbing FL 50 TS 1225:54 APP Tuc {Tucano c/s} Linton Director identified TS climb FL :03 APP Tuc {Tucano c/s} own navigation TACAN hold 1226:20 APP Tuc {Tucano c/s} traffic north east 10 miles tracking west at FL :26 Tuc APP Looking {Tucano c/s} 1228:33 Zone App Zone with a MATZ over flight, there s a COR ft on or against the 4531 east of Linton 6 miles tracking west 1229:21 App Zone Contact 1229:30 Zone App Descending to 4000ft QFE looking for low level descend once west of Linton 1229:31 App Zone Erm roger and you re going to go, you re obviously going to descend lower once your about 5 miles west or something like that 1229:36 Zone App Affirm yeah 1229:40 Tuc App And {Tucano c/s} we ve got traffic coming left 030 degrees 1229:50 App Tuc {Tucano c/s} roger improve course traffic is erm east 1 mile track west 1000ft above descending 1229:58 Portions of the transcript between Linton Zone and Cordite formation is below: From To Speech Transcription Time Cordite Zone Erm Cordite, pair of Tucanos currently 12 miles east of field 7000 ft looking for a TS and a cloud break to low level 15 miles west of Linton 1227:41 Zone Cordite Cordite identified TS 1228:13 Zone Cordite Cordite set Linton QFE :25 Cordite Zone 1000 set Cordite 1228:29 Cordite Zone Cordite ready for descent 1228:40 Zone Cordite Cordite standby 1228:41 Zone Local Zone COR 3000 ft QFE 1228:44 Local Zone COR 3000 ft QFE 1228:47 Zone Local With a pair of Tucanos east to west over the top not below 4000 ft QFE until 5 miles west 1228:50 Local Zone Roger 1228:55 1 Climb-out restriction. 3

81 Airprox From To Speech Transcription Time Zone Copied that {controller name}? 3000 I ll get my pair down to 4 over the top 1228:59 (open mic) Zone Cordite Cordite descend initially not below height 4000 ft 1229:07 Cordite Zone Descend initially not below height 4000 ft cordite 1229:11 Cordite Zone Zone have you got traffic 1000 ft below us 1229:44 Zone Linton Approach, Dishforth Tower 1229:47 Zone Cordite Cordite affirm traffic left 2 miles tracking north east indicating FL :48 Cordite Zone Cordite stopping descent 5700 ft 1229:53 Cordite Zone Cordite visual with that traffic now 1229:57 Zone Cordite Cordite roger visual with that traffic descend to height 4000 ft 1230:00 Cordite Zone We will be filing an Airprox against that traffic erm because you descended us through their level into confliction 1230:15 At 1228:26 (Figure 1), Approach called traffic as, traffic north east 10 miles tracking west at FL75. Figure 1: Traffic Information at 1228:26 (Cordite 4531; single Tucano 4501). At 1229:07 (Figure 2), Zone descended Cordite to not below 4000ft Linton QFE 1000 hpa. 4

82 Airprox Figure 2: Geometry as Cordite stopped in descent to 4000ft at 0929:07. At 1229:21 (Figure 3), Zone placed a climb-out restriction with Zone of 3000ft against the 4531 squawk. Figure 3: Climbout restriction at 1229:21. At 1229:48 (Figure 4), Zone called traffic 2 miles tracking north east indicating FL 50. Tucano (B) transmitted to Approach at 1229:50, we ve got traffic coming left 030 degrees. Figure 4: Traffic Information at 1229:48. 5

83 Airprox Cordite called visual with Tucano (B) at 1229:57 (Figure 5). The CPA was estimated at 1230:06 (Figure 6). Figure 5: Cordite called visual at 1229:57. Figure 6: CPA at 1230:06. The chart at Figure 7 shows the position of the TAC RW28 at Linton. Figure 7: Linton TAC RW28. 6

84 Airprox Linton App controller applied a Traffic Service to Tucano (B) and approved an own navigation climb to FL50 for the TACAN hold. The single Tucano had climbed out for a TACAN hold (Figure 7) and had turned to the left for the IAF, which meant that it flew through the radar overhead. ATC would normally expect a more direct right hand turn from RW28 to position for the hold; however, the Tucano had been instructed to follow own navigation, and had turned left. Traffic Information was given at 10nm when Cordite formation were at FL75. Zone called App with a climb-out restriction and identified Cordite to him when it was 6nm east of Linton, in the descent to 4000ft. No update was provided by App to Tucano(B) as the formation began their descent, and Tucano(B) called visual at 2nm, declaring a left turn 30. Following a request for a descent 15nm west of Linton, Linton Zone placed the formation on the QFE of 1000hPa and, 42 seconds later, approved a descent to 4000ft. Zone passed the 3000ft climb-out restriction to the ADC and then informed App, along with Traffic Information on Cordite. By the time that Zone had passed the 3000ft climb-out restriction, Tucano (B) was at FL50. Zone did not pass any Traffic Information to Cordite and the formation subsequently asked whether there was traffic 1000ft below, 22 seconds prior to CPA. The request for information from Cordite prompted Zone to then pass Traffic Information on Tucano (B) indicating FL50 at 2 nms, 18 seconds prior to CPA. The radar replay demonstrates that the Tucano was in the radar overhead and it is believed that it did not appear on radar to the Zone controller before this time. The Zone controller recalled that Tucano (B) first appeared as Cordite informed him of traffic 1000ft below. Tucano (B) reported spotting the formation on TCAS at the same time as the Traffic Information at 7nm and was visual by 3nm (actual Traffic Information was at 10nm). The instructor/student were not concerned about the confliction; a 10 turn was initiated but it was not considered avoiding action because the crew were content that safe separation existed. Cordite formation had a TCAS alert inside 2nm and were visual at less than 1nm. However, Cordite felt that they had been cleared to descend into confliction as they were cleared to 4000ft against the other aircraft at FL50. The Unit investigation considered that Tucano (B) was lost in the radar overhead at FL50 as the aircraft had taken the long routing for the TACAN hold. Likewise, Cordite picked a routing close to the radar overhead which could have obscured other traffic from ATC. App passed Traffic Information at 10nm but no update was offered despite the closing geometry. Zone did not pass any Traffic Information to Cordite until the aircrew questioned the conflict, but did pass Traffic Information on Cordite to App and Tower. The control team did not limit [the service] for the radar overhead as this is not required locally. The experienced App controller may have considered that everything was in place because he had a track at FL50 and the climb-out restriction had been agreed below this height. The initial Cordite request was for a cloud break descent 15 miles west of Linton and the Zone controller had started the descent to 4000ft whilst still to the northeast of Linton; good practice may have been to keep Cordite level until clear of the busy part of the MATZ. Again, with a climb-out restriction in place, the Zone controller probably lost Cordite in the radar overhead but had been satisfied that any climb-outs were 1000ft below. The Zone controller started the formation descending earlier than requested but was attempting to assist the crews with a cloud break descent whilst protecting the MATZ. The App controller may have made the assumption that Cordite were not a factor prior to his track routing back through the overhead. However, Tucano (B) was already above 3000ft when the restriction was put in place and neither controller were acting upon the information that had been available to them on radar. The radar replay suggests that both tracks were likely to be on converging headings with Cordite descending through the level of the Tucano. CAP774, Chapter 3.5, states that, the controller shall pass Traffic Information on relevant traffic, and shall update the Traffic Information if it continues to constitute a definite hazard. Despite losing traffic in the overhead, it is probable that the information was not assimilated by the App controller or that the controller expected the Tucanos to descend when further west. The Zone controller had distractions in the shape of two landline conversations and a free-call from Dishforth but the overall workload was low. The Unit felt that there was a lack of appropriate 7

85 Airprox action and awareness by both controllers and the issue would be highlighted with a Standards Bulletin and better Team Resource Management. The barriers to an Airprox consisted of ACAS, radar-derived Traffic Information and see-andavoid. ATC had applied Traffic Information at 10nm and a climb-out restriction but the team did not use the information fully and allowed the situation to develop. The routing of both crews had taken them close to the radar overhead, thus introducing the potential for the controllers to lose sight of conflicting traffic. TCAS did provide both crews with situational awareness and this eventually aided visual acquisition. UKAB Secretariat Both pilots shared an equal responsibility for collision avoidance and not to operate in such proximity to other aircraft as to create a collision hazard 2. If the incident geometry is considered as head-on, or nearly so, then both pilots were required to turn to the right 3, if the incident geometry is considered to be converging then Tucano(B) pilot was required to give-way 4, which he did. Comments HQ Air Command This incident highlights the requirement for all personnel to maintain appropriate situational awareness (SA) when involved in the safe operation of aircraft within the wider aerodrome traffic environment. In this instance, a breakdown in communication between the Linton Zone and Approach controllers resulted in a formation of 2 Tucanos being cleared through the level of a similar type manoeuvring for an instrument approach. Following a review of the available documentation, it is evident that the Zone controller believed that he had sanitised the area in which he would descend the Tucano pair by imposing a climb out restriction. However, he was not informed by the Approach controller of the potential for Tucano (B) to conflict with the descending aircraft, as it was already operating above the restriction; Tucano (B) may not have been visible to the Zone controller as it manoeuvred through the radar overhead. The failure of the Approach controller to pass relevant Traffic Information may have been due to distraction leading to an inability to assimilate the information passed from Zone. Distraction may also have prevented the Zone controller from recognizing the potential confliction, as he was diverted by landline coordination at key moments during the event. Given the prevailing weather conditions, both pilots had chosen an appropriate ATS for the activities conducted. However, the choice of both crews to manoeuvre through the aerodrome overhead may have complicated the controllers ability to provide an appropriate service and may have contributed to the incident; greater positive control may have prevented this from occurring. Notwithstanding, the maintenance of SA by both crews, through the use of TCAS, aided visual acquisition and prevented a more serious outcome. Summary An Airprox was reported on 29 th May at 1230 between a single Tucano and a formation of two Tucanos. The formation was receiving a Traffic Service from Linton Zone and had been cleared to descend to 4000ft QFE; the controller imposed a climb-out restriction on Linton aircraft and believed that would protect his aircraft from traffic departing Linton. Tucano (B) was receiving a Traffic Service from Linton App and was already climbing for the TAC hold and passing FL50; Linton App passed Traffic Information on the conflicting formation at a range of 10nm. Both pilots received TCAS alerts, and both became visual with the conflicting traffic. 2 SERA.3205 Proximity. 3 SERA.3210 Right-of-way (c) (1) Approaching head-on. 4 SERA.3210 Right-of-Way (c) (2) Converging. 8

86 Airprox PART B: SUMMARY OF THE BOARD'S DISCUSSIONS Information available consisted of reports from the pilots of both aircraft, transcripts of the relevant RT frequencies, radar photographs/video recordings, reports from the air traffic controllers involved and reports from the appropriate ATC and operating authorities. The Board first looked at the actions of the Tucano formation; they noted that the crew had called for a cloud-break whilst they were to the east of Linton, heading west. Whether they expected to be able to descend through the overhead, or whether the Zone controller was trying to be helpful by allowing them to descend early was not clear, but the Board highlighted that planning to descend through cloud very close to or through, the radar overhead is rarely best practice due to likely loss of radar contact. As it transpired, the formation did not receive Traffic Information from the controller because it was likely that the conflicting traffic was not showing on his radar screen. Nevertheless, in the end the Board noted that the pilots had been alerted to the possible confliction by their TCAS, and had used that information wisely in electing to level-off above the height of the other Tucano. The Board noted that the pilot of Tucano (B) was less concerned by the incident. He had received Traffic Information from the Approach controller and so was primed to look for the other traffic, eventually seeing it and deciding it wasn t a factor. Again TCAS played a part in providing further situational awareness on the formation, and the Airprox as a whole highlighted the value of TCAS. The Board then looked at the actions of the controllers. They opined that the Zone controller had probably thought he had done enough to protect his aircraft; he had notified Tower and Departures, put a climb-out restriction in place, and had provided Traffic Information to the Approach controller. The Board noted that the wisdom of descending aircraft through the radar overhead was mentioned in the unit investigation, and they reiterated this, although recognising that circumstances sometimes dictated otherwise. The Board also noted that, although local orders stated that controllers didn t need to tell pilots that the ATS would be limited when passing close to the radar overhead, it was felt that this could have acted as a timely reminder that more robust look-out may be required in these circumstances. Turning to the Approach controller, the Board wondered why he had not realised that his aircraft would be a factor when the Zone controller passed Traffic Information on the formation. Some members wondered if he might have momentarily forgotten his aircraft was there due to distraction, or because he couldn t see it on his radar as it transited through the radar overhead. More likely they thought, it may also have been that he simply didn t assimilate that Zone intended to descend the formation through the overhead because to do so was not a normal occurrence. The Board were disappointed that an oversight by Linton meant that there was not a report from the Approach controller, and so the controller s reasoning could not be determined. However, what was not in doubt was that by not informing Zone that his traffic was already through the level of the climbout restriction, the Approach controller had introduced risk of conflict. When determining the cause of the Airprox, the Board quickly agreed that it was that Linton ATC had not sufficiently synchronized the Tucano formation with Tucano (B). The risk was assessed to be Category C; timely actions were taken to prevention a collision. PART C: ASSESSMENT OF CAUSE AND RISK Cause: Linton ATC did not sufficiently synchronize the Tucano formation with Tucano (B). Degree of Risk: C. 9

87 AIRPROX REPORT No Date: 23 May 2015 Time: 0904Z Position: 5138N 00033W (Saturday) Location: Denham Airfield PART A: SUMMARY OF INFORMATION REPORTED TO UKAB Recorded Aircraft 1 Aircraft 2 Aircraft PC12 C152 Operator Civ Comm Civ Club Airspace London FIR London FIR Class G G Rules VFR VFR Service A/G Service A/G Service Provider Denham Radio Denham Radio Altitude/FL 1100ft 1000ft Transponder A, C, S A, C, S Reported Colours Gold Red, white, blue Lighting Nav, beacon NK landing Conditions VMC VMC Visibility 10km >10km Altitude/FL 1000ft 1200ft Altimeter QNH (NK hpa) QNH (1024hPa) Heading Speed 120kt 75kt ACAS/TAS TCAS I Not fitted Alert TA Nil Separation Reported 0ft V/20m H 0ft V/150m H Recorded 100ft V/<0.1nm H THE PC12 PILOT reports performing a full-circuit pattern due to 3 aircraft ahead, routeing St Giles VRP, Denham, Maple Cross VRP, St Giles VRP. When approaching St Giles VRP for the second time the co-pilot saw another aircraft, very close on the right side and in a left turn. The pilot took avoiding action and, simultaneously, the crew received a TCAS Traffic Alert. The pilot noted that neither Denham Radio nor they were aware of this new aircraft in the circuit pattern. He did not make an assessment of the risk of collision. THE C152 PILOT reports instructing a circuit training exercise. The circuit was congested so they departed via Maple Cross VRP. Whilst tracking towards St Giles VRP, a practice go-around was conducted at height, and the student (PF) started to turn left. The instructor asked him to level the wings so that they could continue to track towards St Giles VRP, at which point he saw the underside of a gold turbo-prop aircraft, co-altitude about m away, overtaking them in a level hard left turn; he did not have time to take avoiding action. The instructor reported the Airprox to Denham Radio, who did not acknowledge the call. He assessed the risk of collision as High. THE DENHAM A/G OPERATOR did not submit a report. 1