I ATC Training Department / South East RTS UK Flight Information Services (FIS) (Formerly: Air Traffic Services Outside Controlled Airspace) REVISION 3 (Monday, 16 February 2015 at 14:15) PUBLISHED Monday, 16 th February 2015
Contents Contents... 2 Section - 1 This Document... 4 Section - 2 Introduction to Services... 5 2.1 Basic Principles... 5 2.1.1 Class E Airspace... 5 2.2 Provision, Upgrade and Downgrade... 5 Section - 3 Services... 7 3.1 Basic Service... 7 3.1.1 Responsibility... 7 3.1.1 Generic Traffic Information... 7 3.1.2 Correct Pressure... 8 3.2 Traffic Service... 8 3.2.1 Responsibility... 8 3.2.2 Provision... 9 3.2.3 Traffic Information... 9 3.3 Deconfliction Service... 11 3.3.1 Responsibility... 11 3.3.2 Provision... 12 3.3.3 Descent below terrain safe levels... 12 3.3.4 Deconfliction minima... 13 3.3.5 Deconfliction advice... 13 3.3.6 Avoiding Action... 14 3.3.7 Exception to terrain safe levels*... 14 3.4 Procedural Service... 15 3.4.1 Provision... 15 3.4.2 Traffic Information... 15 3.4.3 Procedural Deconfliction... 15 Section - 4 Themes/Principles... 18 4.1 Identification*... 18 4.2 Terrain Safety... 18 4.2.1 Basic Service... 18 4.2.2 Traffic Service... 18 2 / 24
4.2.3 Deconfliction Service... 19 4.2.4 Procedural Service... 19 4.3 Co-ordination... 19 4.3.1 Request Co-ordination... 20 4.3.2 Radar Handover... 21 4.3.3 Further Co-ordination... 21 4.4 Workload... 21 4.4.1 Reduced Traffic Information/Deconfliction... 21 4.4.2 Level of Service... 22 4.5 Agreements... 22 Section - 5 Acknowledgements... 24 Section - 6 Other Documentation... 24 6.1 Related VATSIM UK Documents... 24 6.1.1 Introduction to Radar... 24 6.1.2 Co-ordination... 24 6.2 Further Reading... 24 6.2.1 CAP493 Part 1... 24 6.2.2 CAP774... 24 6.2.1 CAP413... 24 3 / 24
Section - 1 This Document This document is mainly targeted at S2s training to S3 and any visiting controller wanting to understand the UK Flight Information Services. The document is split up into general principles and then a section on each of the 4 Flight Information Services, including example RT that you can apply. Example scenarios listed in this document are based upon the SERTS airfields: Gatwick, Thames, Solent, Farnborough (for all but procedural) and Shoreham, Biggin and Lydd for Procedural Service. These examples are kept as generic as possible for application across the UK. As this document is not intended to cover all eventualities, not everything is covered within. Included are certain extra sections that I consider relevant and worth being aware of. These sections are either information on another subject, or information not deemed to be Core information for understanding Flight Information Services. Any section that is considered Additional is marked with an asterisk (*). RT examples will be coded as follows: Gatwick Gatwick Director,., Gatwick Director, pass your message. This document has been created for the purpose of training in the UK division on the VATSIM network. This document should not be considered a reference for any real-world procedures, nor should be used by other organisations without the prior permission of the author. 4 / 24
Section - 2 Introduction to Services 2.1 Basic Principles Aircraft operating in Class G airspace are considered to be Outside Controlled Airspace (OCAS) and as such then become responsible for collision avoidance and terrain clearance. Whilst in Class G airspace, pilots do not have to be in contact with an ATSU (Air Traffic Service Unit) and those which are in contact are not required to comply with ATC instructions. Because of this aircraft are not offered a Control Service OCAS, but instead are offered one or more of four Flight Information Services (FIS). There is no Class F airspace in the UK. The UK Flight Information Services are: Basic Service (IFR and VFR traffic) Traffic Service (IFR and VFR traffic) Deconfliction Service (IFR traffic only) Procedural Service (IFR traffic only) All of these services can be offered in ANY meteorological conditions. However, as pilots are expected to accept advice given under the service they should not request a service which isn t suitable to their qualification/ability/situation and should select the most appropriate to their conditions. 2.1.1 Class E Airspace Class E airspace is controlled airspace. Significantly there is no requirement for VFR flights to gain clearance to enter or to communicate with ATC. VFR flights operating in Class E airspace who contact ATC and request a service are to be provided with one of the Flight Information Services (Basic Service or Traffic Service), not a 'Control Service'. IFR flights in Class E airspace (on a Radar Control Service) are to be provided with traffic information on all known VFR flights. Traffic avoidance will be given only if requested. 2.2 Provision, Upgrade and Downgrade When a pilot is provided with a service the controller is to inform them of the service they will receive. Should the service subsequently change, the pilot must be informed so that they are aware of what information they can expect to receive. Example: Pilot requests Basic Service KK INT Gatwick Director, request Basic Service, Gatwick Director, pass your message. 5 / 24
Gatwick Director,, Cessna 172, routing Biggin to Shoreham 3 miles west of Mayfield, at 1700ft VFR, QNH 1004 request Basic Service KK INT G-CD, roger. Basic Service, Gatwick QNH 1003. Basic Service, QNH 1003, G-CD. If you are unable to provide the service anymore, the service should be downgraded or cancelled. Example: G-AADF, IFR currently under Deconfliction Service agreed to maintain 2300ft but now requests descent G-AADF G-AADF G-DF, request to descend to altitude 1000ft, VFR G-DF, roger VFR, Traffic Service. Taking your own terrain clearance, descent approved Traffic Service, my terrain clearance, descending to 1000ft, G-DF. The reason for the downgrade in this situation is due to the pilot requesting VFR. Because he is descending below terrain safe level he is also provided with a terrain warning this is explained in the deconfliction section. You should not provide information that isn t specified under the service you are providing (unless you deem imminent danger to the flight). If you are going to provide further service, you should inform the pilot of the upgrade. Example: G-BFCK, IFR currently under Basic Service due to being outside of radar coverage, though Traffic Service previously requested asked to report abeam GWC. G-BFCK G-CK passing abeam Goodwood at altitude 2600ft. G-CK, squawk 3661 G-BFCK Squawk 3661, G-CK G-CK, identified. Traffic Service. Traffic South, 6 miles, tracking north indicating 3200ft unverified. 6 / 24
Example: Pilot switching to a different station and service being cancelled G-AFDC G-DC, request a frequency change to Biggin Approach 129.4 Gatwick G-AFDC G-DC, squawk 7000, radar service terminated. Frequency change approved. Squawk 7000, G-DC Section - 3 Services 3.1 Basic Service A Basic Service is: an ATS provided for the purpose of giving advice and information useful for the safe and efficient conduct of flights. Examples of information you could give under a Basic Service: Weather information Aerodrome Conditions/services General Airspace activity information Safety related information Generic traffic information (See Example 3-1) 3.1.1 Responsibility As with all FISs, it is the pilot s responsibility to avoid traffic, maintain terrain clearance and comply with the rules of flight. Additionally under a Basic Service, there is no requirement for the pilot to notify you of routing or level changes unless they have entered into an accord with you (see 4.5). 3.1.1 Generic Traffic Information You do not need to identify or monitor a flight under a Basic Service unless to do so would be beneficial to the controller e.g. for reasons of coordination. As such, traffic information is not a requirement under a Basic Service (the exception being when controlling ATZ in Class G airspace). Any traffic information given should not be surveillance derived and should be in general terms only (see note below). Example: Generic Traffic Information for aircraft under Basic Service G-EA gliding activity at Kenley to altitude 2000ft. G-DC, Police helicopters operating north of M11 junction 5 below altitude 1000ft G-OA, Fast Jets operating south of St Catherine s point below altitude 3000ft 7 / 24
Note: although traffic information should be generic, a controller has a duty of care to the pilot and therefore should he have information relating to safety (e.g. if the aircraft was identified under a Basic Service and a hazard appears) then this should be passed. 3.1.2 Correct Pressure When providing any Air Traffic Service it is useful to know what pressure setting to provide a pilot with. In general, the pilot should be on one of three categories of pressure: Standard Pressure (1013.2hPa) Local Pressure (i.e. the pressure at an aerodrome) Regional Pressure (e.g. Chatham, Portland, Barnsley etc) An aircraft operating above the transition altitude should operate on standard pressure. Transition altitudes are different depending on the airspace so the transition altitude where the aircraft is may be different to the facility you are covering. You should not need to provide this pressure setting to a pilot (it is standard!). The transition altitude in the UK is 3000ft unless otherwise specified (e.g. in the London TMA it is 6000ft). Local pressure (where available) is to be provided to aircraft operating outside of controlled airspace under airspace with a base which is an altitude. The pressure of the most appropriate facility available should be passed along with the identity of the facility that the pressure is obtained from: G-FC, Southampton QNH 998 hectopascals Regional pressure is provided when the aircraft is operating under airspace with a base of a flight level where they are also below transition altitude. When providing an RPS you only need to specify the regional name and the pressure (the phrases regional or QNH are not included). G-AB, for coordination request maintain altitude 2000ft, Portland 1030. 3.2 Traffic Service A Traffic Service is a surveillance-based service and as such can only be provided by controllers with appropriate radar coverage (usually a minimum of Primary Radar). Under a Traffic Service a controller provides the same information as under a Basic Service in addition to surveillance derived traffic information. 3.2.1 Responsibility As with all the FISs, it is ultimately the responsibility of the pilot to avoid traffic and the controller does not have to maintain deconfliction minima however a controller may provide headings and levels to assist in navigation or sequencing. 8 / 24
It is important to consider terrain safety before issuing a heading to an aircraft outside of controlled airspace (see 4.2 Terrain Safety). If the pilot requests deconfliction advice for any stated traffic this is to be treated as a request for a Deconfliction Service. The pilot is expected to provide the controller with information on their routing including notification of when they intend to change course or level. 3.2.2 Provision It is required that you identify an aircraft prior to providing a Traffic Service. For information on identification of aircraft, see (4.1 Identification). Gatwick Gatwick Director, request Traffic Service, Gatwick Director, pass your message., Piper Archer, en-route from Bournemouth to Elstree, 5 miles east of Goodwood, tracking East to Handcross at 2100ft, QNH 1017hPa VFR, request Traffic Service Gatwick G-CD squawk 3750 Gatwick QNH 1016 Gatwick Squawk 3750, QNH 1016 G-CD G-CD, Identified. Traffic Service Traffic Service, G-CD. Note that the aircraft has passed his level to you. You have the responsibility of verifying his Mode C readout when providing him with a discrete squawk code as other controllers are therefore able to use this for traffic information (examples below). 3.2.3 Traffic Information 3.2.3.1 Provision of Traffic Information Under a Traffic Service, you pass surveillance-derived traffic that it considered relevant. The general guideline for relevant traffic is traffic that will pass within 3NM and 3000ft. However you have discretion as to what you consider relevant based upon the situation. Ideally the traffic information should be passed before the distance between aircraft is 5NM. As an example, traffic on an opposite heading 1000ft above that will likely pass within 1NM would definitely be relevant whereas an aircraft passing 2NM behind the aircraft under a Traffic Service (i.e. perpendicular to its track and diverging) may not be relevant. If you are in doubt pass the traffic information. Traffic information should be updated if the situation changes and the traffic is still relevant. Should the traffic become a hazard then you should update the pilot immediately. Subject to workload, the pilot may be informed that he is clear of the previously mentioned traffic. 9 / 24
3.2.3.2 Format of Traffic Information [CALLSIGN], traffic [POSITION], [DISTANCE], [SPEED], [DIRECTION], [LEVEL] Position: Position can be passed in one of two ways. The preferred method is to provide it as a clock code with respect to the facing direction of the pilot (optionally with a prefix of left or right for convenience for the pilot). However this is not always possible e.g. if the aircraft receiving the service is turning this will not only be hard to ascertain but will become quickly inaccurate. In this situation the position is passed as a cardinal direction. Distance: The distance between the traffic under a service and the conflicting traffic in miles. Speed: If relevant and relative to the aircraft, e.g. fast moving, slow moving. Direction: While it is not always possible to provide the exact intention/routeing of aircraft, you should attempt to give as much information as possible to improve the situational awareness of the pilot. This information is given in one of the following forms: Closing Converging Crossing left to right Crossing right to left Opposite Direction Diverging Same Direction/Parallel Tracking [Cardinal Point] Level: Where available the level of the aircraft should be given by one of the following methods dependent upon situation: indicating xxxxft when traffic has verified Mode C data indicating xxxxft unverified when the traffic has a Mode C readout that is not (or cannot be) verified indicating similar level it is preferable to be more specific than this if possible, however this can be used if the other traffic has a fluctuating level coordinated xxxx feet above/below to be given when the traffic is separated by asking an aircraft to maintain a level, or traffic known to maintain a level due to coordination xxxx feet above/below cleared level given to an aircraft climbing or descending to a known level no height information or height unknown if there is no information on the height (i.e. no Mode C readout, and no reported level) last reported at xxxx feet to be given by a station with primary only radar return The word unverified must be appended to any height information which has not been verified. 10 / 24
3.2.3.3 Examples of Traffic Information G-BD, traffic left 10 o clock, 5 miles, crossing left to right, height unknown G-ZA, traffic East, 3 miles, tracking north, indicating 2300ft unverified Gatwick G-GG, traffic 6 o clock, 6 miles and reducing, fast moving, same direction, no height information G-FA, traffic a Cessna 182, 8 o clock, 5 miles, parallel, coordinated 2000ft below. Fraction 15H, traffic, Piper Seneca 12 o clock, 7 miles, opposite direction indicating similar level 3.3 Deconfliction Service A Deconfliction Service is also a surveillance-based service in which the controller provides a Basic Service, surveillance-derived traffic information (as in a Traffic Service) plus headings/levels to achieve deconfliction minima. It is available only to IFR flights. Traffic information should be passed on all relevant traffic, though you do not need to provide deconfliction advice on traffic which is inside controlled airspace unless there is reason to believe the traffic is exiting. A Deconfliction Service may not under any circumstances be provided below the terrain safe levels. Refer to local documentation to find the MSA (minimum safety altitude) for the area you are controlling. Should the pilot wish to descend below MSA then the service must be downgraded. 3.3.1 Responsibility A common misconception with this service is the responsibility for deconfliction. As stressed in this document, under any FIS (including Deconfliction Service) it is ultimately the responsibility of the pilot to avoid other traffic. As with Traffic Service, the pilot is expected to provide the controller with information on changing their routing and is expected to follow the deconfliction advice given. If the pilot chooses not to follow deconfliction advice (e.g. if they have the traffic in sight) the pilot is only to be passed traffic information until he is clear of the traffic. You may pass further traffic information if you believe there is a hazard. If the pilot is unable to follow deconfliction advice this is to be treated as a request to downgrade his service. 11 / 24
3.3.2 Provision As with Traffic Service, you are required to identify an aircraft before providing a Deconfliction Service. Thames Radar, request Deconfliction Service., Thames Radar, pass your message, Seneca, routing Clacton to Lydd, 15 miles south west of Clacton at FL40 IFR request Deconfliction Service G-CD, Squawk 7070 Squawk 7070, G-CD G-CD identified. Deconfliction Service Deconfliction Service, G-CD G-WXYZ G-WXYZ G-WXYZ Thames Radar, G-WXYZ request Deconfliction Service. G-WXYZ, Thames Radar, pass your message G-WZYZ, Seneca, routing Cambridge to Lydd 5 miles south west of Southend at 1900ft QNH 997hPa IFR, request Deconfliction Service G-YZ, unable at your level. Is Traffic Service acceptable? Affirm, G-YZ G-YZ squawk 7070, London QNH 1023 G-WXYZ G-WXYZ Squawk 7070, QNH 1023 G-YZ G-YZ, identified. Traffic Service Traffic Service G-YZ 3.3.3 Descent below terrain safe levels Should an aircraft request a descent below terrain safe levels, you may no longer provide them with the Deconfliction Service and as such it should be downgraded. G-AADF G-DF, request descent to altitude 1000ft 12 / 24
G-DF, Traffic Service. Taking your own terrain clearance, descent approved G-AADF Traffic Service, my terrain clearance, descending to 1000ft, G-DF. 3.3.4 Deconfliction minima Deconfliction minima change depending upon whether the traffic is controlled/coordinated or uncoordinated. Minima against aircraft under a service from the same controller or have been previously coordinated: 5NM laterally (when approved by the CAA, reduce to 3NM). Refer to local documentation. or 1000ft vertically. Against un-coordinated or unknown traffic the deconfliction minima increases to: 5NM laterally or 3000ft vertically and the radar returns should not be allowed to merge. While you are not ultimately required to achieve these minima, your deconfliction advice should provide a route (where possible) for this separation to be maintained. 3.3.5 Deconfliction advice Deconfliction advice consists of traffic information plus an instruction for if the pilot does not have the aircraft in sight. The pilot will indicate through their response whether they intend to follow the deconfliction advice. If the pilot follows the deconfliction instruction, the controller should inform the pilot when the conflict no longer exists. G-CD, traffic 2 o clock, 6 miles, opposite direction indicating 2500ft unverified. If not sighted turn left heading 210 degrees. Left heading 210 degrees, G-CD. G-CD, clear of traffic resume own navigation direct Southampton. Gatwick G-DHGS G-GS, traffic 3 o clock, 7 miles, converging, indicating FL55 unverified. If not sighted turn left heading 250 degrees. Visual, continuing, G-GS 13 / 24
G-HS, traffic left 7 o clock, 6 miles, converging, no height information. If not sighted turn right heading 360 degrees. G-PPHS Continuing VMC, G-HS 3.3.6 Avoiding Action In cases where the controlled believes there needs to be immediate action by the pilot (i.e. there is imminent risk of collision), avoiding action should be passed which should include the phrases avoiding action, immediately with traffic information being passed after the avoidance instruction. Gatwick G-PF, avoiding action turn left immediately heading 120 degrees. Traffic 12 o clock 2 miles, opposite direction, same level. G-GFPF Left heading 120 degrees, G-PF Again as with deconfliction, the pilot can refuse the instruction and continue as before. Gatwick G-PF, avoiding action turn left immediately heading 120 degrees. Traffic 12 o clock 2 miles, opposite direction, same level. G-GFPF Visual, continuing, G-PF 3.3.7 Exception to terrain safe levels* The only times a Deconfliction Service can be provided when an aircraft is operating below terrain safe levels is when an aircraft is departing from an aerodrome and climbing to terrain safe levels or when flying notified instrument approach procedures. 3.3.7.1 Departure from an Aerodrome* Deconfliction service can be provided to an aircraft departing from an aerodrome and climbing to terrain safe levels. If conflictions exist, ATC will usually pass traffic information without deconfliction advice. However should there be imminent danger or the pilot requests it avoiding action can be given but this must be accompanied with a terrain safety warning. ATC WOW4F Swallow 4F avoiding action, turn left immediately heading 210 degrees. Caution terrain. Traffic 6 o clock, 1 mile, closing indicating 1200ft unverified. Left heading 210 degrees, roger, Swallow 4F 3.3.7.2 Notified Instrument Approach* If under a Deconfliction Service on an instrument approach below terrain safe levels then deconfliction is passed along with a climb to terrain safe levels therefore resulting in the need for repositioning. In cases where the approach is not pilot interpreted (e.g. an SRA) then if the controller can keep the aircraft within terrain safe levels and continue the approach following deconfliction 14 / 24
then a climb is not required. However should deconfliction result in repositioning, a climb will always be given. 3.4 Procedural Service A Procedural Service is not a Surveillance-based service. It consists of a Basic Service plus instructions/restrictions/clearances to achieve procedural deconfliction minima against other aircraft which are participating in a Procedural Service. As such, it cannot deconflict against unknown traffic. Procedural Service is available only to IFR flights. As with all FISs it is the responsibility of the pilot to avoid other aircraft. The pilot will also inform the procedural controller when they have to deviate from procedural instructions. Identification is not required for a Procedural Service, however often a squawk code is given so that other surveillance units are aware that an aircraft is under a Procedural Service with a given unit. 3.4.1 Provision Not every ATC unit without surveillance systems may offer Procedural Service. Usually Procedural Service is provided by an approach controller where there are published instrument approach procedures with no radar facility or at airfields where identification cannot be maintained in the holding pattern. Refer to local documentation to ascertain the unit offers this service to pilots. An IFR arrival making contact with a procedural approach unit will usually be given Procedural Service without the pilot having requested it as would most IFR departures however in other cases the pilot should be asked what service is required. Procedural service is available below terrain safe levels, however this is only usually on a published approach or climbing to MSA. When an aircraft is operating below terrain safe levels for other reasons, the pilot should be reminded that terrain avoidance is his responsibility. 3.4.2 Traffic Information As the controller may well be in contact with other pilots than those under Procedural Service, traffic information can be passed where traffic is known (e.g. under a Basic Service, or coordinated by another unit). While aircraft under Procedural Service should be separated from each other there is no reason why a procedural controller cannot pass traffic information on these flights to others participating, solely to improve situational awareness. 3.4.3 Procedural Deconfliction A procedural controller can achieve deconfliction vertically, or by using radials/tracks from beacons and time restrictions. Vertical deconfliction minima under a Procedural Service are 1000ft vertically or 500ft vertically when applying the quadrantal rule. Lateral and longitudinal minima are detailed in MATS Part 1 Section 1 Chapter 3 paragraphs 6, 7 and 8. Should an aircraft requiring Procedural Service contact the approach unit with a position that means that separation is less than the deconfliction minima then essential traffic information is passed and together with advice to achieve the deconfliction minima (usually a climb to 1000 feet above the traffic already in receipt of a Procedural Service) if possible. 15 / 24
3.4.3.1 Phraseology Examples It is impossible to provide phraseology examples for all eventualities of Procedural Service. Therefore the following is an example of a procedural approach into Shoreham (NDB DME) and an example of traffic information on an aircraft under Basic Service. Refer to other documentation for a more extensive description of Procedural Service. Shoreham Approach,, DA42 inbound from Bournemouth 15 miles west of SHM at 3000ft QNH 1013, IFR estimating SHM at time 16. Shoreham Procedural Service, squawk 0401, cleared to the SHM at 3000 feet, no delay for the NDB DME approach runway 20, QNH 1012 Squawk 0401, Procedural Service, cleared to SHM at 3000ft QNH 1012, no delay Shoreham G-CD Descend to altitude 2200ft, cleared NDB DME approach runway 20 report beacon outbound and passing 2500ft Descend to 2200ft. Cleared NDB DME approach runway 20, wilco, G-CD Shoreham Shoreham Shoreham Beacon outbound, G-CD G-CD, report base turn complete Wilco, G-CD Passing through 2500ft, G-CD G-CD, roger Base turn complete G-CD report 3 DME. Wilco, G-CD Note the use of requesting the pilot to report passing 2500ft in this example. The controller may have another aircraft inbound to SHM wanting to use a lower holding level (i.e. 3500ft), so the pilot is requested to report passing a separated level. G-GFGF Shoreham G-GFGF Shoreham G-GFGF Shoreham Approach, G-GFGF request Basic Service G-GFGF, Shoreham Approach, pass your message. Shoreham Approach, G-GFGF, Cessna 172, inbound from Southampton 2 miles east of Goodwood at FL45 IFR G-GF, roger. Basic Service. For co-ordination request that you descend to not above 3000ft, Shoreham QNH 1015 Basic Service, descending to not above 3000ft, QNH 1015, G-GF 16 / 24
Shoreham G-CD, traffic reported 2 miles east of Goodwood, a Cessna 172 coordinated descending to not above 3000ft. Roger, G-CD 17 / 24
Section - 4 Themes/Principles 4.1 Identification* In order to provide a Traffic Service or Deconfliction Service, an aircraft has to be identified on radar. The aircraft can then be provided with a surveillance service. Identification can be achieved through one of 4 main methods: SSR, Turn method, Departure Method, Positions Report. The most common of the 4 is often Secondary Surveillance Radar, however this is not always available and as such other methods can be useful. Any time an aircraft is identified when outside of controlled airspace, the pilot is to be informed that they are identified via RT. Additionally, any aircraft identified by the turn method must be told that they are identified, plus their position passed via RT. A previously validated code can be deemed to have had their mode C validated to within 200ft. Further information on the methods of identification can be found in Introduction to Radar (Section 6) produced for VATSIM UK by Chris Pawley. 4.2 Terrain Safety The pilot is not only responsible for avoiding aircraft when outside of controlled airspace, but also terrain. As such there are specific rules as to when you can provide services below terrain safe levels. 4.2.1 Basic Service Agreements to maintain altitudes below terrain safe levels may be made without the need to remind pilots about terrain safety. 4.2.2 Traffic Service Pilots should be reminded of their terrain avoidance responsibility when: You enter an agreement of an altitude below terrain safe levels The aircraft reports his intention to descend below MSA You enter an agreement of a heading while below terrain safe levels This does not apply to notified instrument procedures. Example: Descending below MSA at the request of the controller when under a Traffic Service. Note the change in RT whereby this is usually phrased as a request prior to an instruction. for co-ordination, can you accept a descent to not above altitude 2000ft Affirm, G-CD, taking your own terrain clearance, descend to altitude 1500ft. 18 / 24
My terrain clearance, descending to 1500ft, G-CD Example: Providing a heading to an aircraft below MSA G-AHGV G-ABGV G-GV request a heading to Southend G-GV, taking your own terrain clearance, suggest heading 030 degrees My terrain clearance, flying 030 degrees, G-GV. Examples: Entering controlled airspace with an altitude restriction below MSA Gatwick G-BVOA G-OA cleared to enter the Gatwick Control Zone VFR via the Dorking VRP. Not above altitude 1500ft. Cleared to enter Gatwick Control Zone, VFR via Dorking, not above altitude 1500ft, G-OA 4.2.3 Deconfliction Service Under a Deconfliction Service the pilot is still responsible for terrain safety, however Deconfliction Service is only to be provided to aircraft above the ATC Unit Minimum Safe Altitude. The exceptions to this rule are detailed in the Deconfliction Service section. Should an aircraft wish to descend below terrain safe levels their service should be downgraded. 4.2.4 Procedural Service A pilot may operate below terrain safe levels under a Procedural Service terrain clearance always being the responsibility of the pilot. Except for notified instrument approach procedures or on departure from an aerodrome, the pilot is to be warned of his responsibility for terrain clearance if he wishes to descend below MSA. G-BHDG Shoreham G-BHDG G-DG, request descent to altitude 1000ft G-DG, taking your own terrain clearance, descent approved My terrain clearance, descending to 1000ft, G-DG. 4.3 Co-ordination Aircraft operating in the same (or nearby) area may be receiving a service from different controllers. Co-ordination can therefore be invaluable to controllers for example to eliminate the need for unnecessary deconfliction advice. 19 / 24
In order to co-ordinate, a controller must know which ATSU that aircraft is in contact with. This is most often established through the use of approach unit codes, conspicuity codes or listening codes. For more information on this topic, see Introduction to Radar Section 6 produced by Chris Pawley for VATSIM UK. 4.3.1 Request Co-ordination If you are providing an aircraft with a Deconfliction Service and it comes into conflict with traffic being worked by another controller you can either provide advice to maintain 5nm or 3000ft separation or you can co-ordinate the traffic with the other controller. This means that you call the other controller and both agree a plan of action that will ensure 5nm or 1000ft separation (or 3NM where approved by the CAA refer to local documentation). The telephone call should take the following format: 1. "Request co-ordination" 2. Identify your traffic to the other controller 3. The other controller will respond with "identified" or "contact" 4. Pass details of your traffic and identify the traffic of concern being worked by the other controller 5. The other controller will pass details on his traffic and may suggest a plan 6. Agree the co-ordination Below are a couple of examples of co-ordination. Gatwick Gatwick Gatwick Gatwick INT Thames, request co-ordination, my 7070 squawk, 3 miles East of Biggin tracking West Identified, pass your message. Citation maintaining 2300ft. Request your 3750 squawk not above 1300ft until clear. My 3750 is a PA28 not above 1300ft until clear of your 7070 squawk, coordinated. Gatwick Gatwick Gatwick INT Solent, request co-ordination, my 3660 squawk, 3 miles North East of Goodwood tracking 060 Identified, pass your message Cessna 182 maintaining 3100ft. Request your 3753 squawk not above 2100ft until clear 20 / 24
Gatwick Unable due traffic. Maximum 2500ft. 3660 to climb to altitude 3500ft, my 3753 to maintain 2500ft until clear? 3660 to maintain 3500ft until clear of 3753 maintaining 2500ft, coordinated. 4.3.2 Radar Handover Following coordination, where an aircraft is to be transferred to another controller to continue the radar service transfer of control is to be completed by radar handover. The radar handover must include transfer of identity. An example of a radar handover is shown below (coordination has already happened and the aircraft has been positioned as agreed): Southend Southend Southend Radar Thames, radar handover on GABCD Pass your message GABCD bearing 350 degrees from Detling, 7 miles, level 2300ft, own navigation Southend, Deconfliction Service, squawking 3214. Southend GABCD identified, expect Deconfliction Service, contact 130.775 4.3.3 Further Co-ordination Further coordination examples can be found in Co-ordination produced by Callum Presley for VATSIM UK. 4.4 Workload 4.4.1 Reduced Traffic Information/Deconfliction Sometimes controllers are unable to provide traffic information before the traffic comes within 5 miles for various reasons. If the controller knows that this is likely to happen, the pilot should be informed including the reason and duration (if known) that the reduced service will continue for. This will prompt the pilot to be more vigilant when looking for traffic rather than relying on the controller. Reasons for reduced traffic information could include: Controller workload Aircraft entering areas where the traffic density is very high Limitations of radar coverage o Limits of primary/secondary coverage o Only primary or secondary coverage of the area of the flight o Clutter on the display (e.g. weather returns, terrain reflections) 21 / 24
G-AF, reduced traffic information, SSR only G-GA, possible late warning of traffic for next 10 miles due high traffic density G-FC, reduced traffic information from below for 5 miles due to radar coverage 4.4.2 Level of Service It is important that both the controller and the pilot are aware at all times what service is being provided and therefore what information is expected to be being transferred. In cases where reduced information is available the pilot should be made aware as soon as possible, preferably with an estimate of the duration of reduced information. If a controller is not going to be able to provide the information relating to the service (or indeed if local documentation stipulates a maximum number of aircraft that can be provided with Flight Information Services) then the service should not be provided to the pilot or downgraded as appropriate. Flight Information Services provision is always subject to controller workload and (where applicable) traffic inside controlled airspace is the radar controller s primary concern. As such the service provided should not be detrimental to the service of aircraft under air traffic control services. 4.5 Agreements A controller can ask a pilot to operate with restrictions for a limited amount of time in order to allow other pilots to use the airspace more efficiently. This can be useful in order to avoid unnecessary deconfliction advice, providing more useful traffic information to pilots or even to coordinate actions with other controllers. When a pilot makes an agreement with a controller (e.g. to keep their altitude to not above a certain level) they shouldn t deviate from this without first informing the controller except during safety critical situations. G-CD, for co-ordination, request maintain altitude 2300ft. Maintaining 2300ft, G-CD G-CD, for co-ordination, request fly heading 010 degrees Unable due IMC, G-CD 22 / 24
G-CD, for co-ordination, request operate no further north of your current position No further north of current, G-CD 23 / 24
Section - 5 Acknowledgements Thanks for help in the production of this document go to Callum Presley, Chris Pawley, George Wright and Daniel Parkin for their contributions, proof reading, corrections and suggestions. Author: Kieran Hardern Section - 6 Other Documentation 6.1 Related VATSIM UK Documents 6.1.1 Introduction to Radar A document produced outlining radar theory, identification, verification and validation. http://www.vatsim-uk.co.uk/website/download/info/?downloadid=00208 Author: Chris Pawley At this time of writing: Version 1.0 (Revision 7), released 26 th Feb 2012 6.1.2 Co-ordination A document produced outlining co-ordination between ATSUs. http://www.vatsim-uk.co.uk/website/download/info/?downloadid=00110 Author: Callum Presley At this time of writing: Version 2.0 (Revision 2), released 16 th January 2012 6.2 Further Reading 6.2.1 CAP493 Part 1 CAA: Manual of Air Traffic Services Part 1 http://www.caa.co.uk/cap493 6.2.2 CAP774 CAA: UK Flight Information Services http://www.caa.co.uk/docs/33/cap774.pdf 6.2.1 CAP413 CAA: Radiotelephony Manual http://www.caa.co.uk/docs/33/cap413.pdf 24 / 24