AIRCRAFT ACCIDENT REPORT AND EXECUTIVE SUMMARY

Transcription

1 Section/division Accident and Incident Investigation Division Form Number: CA 12-12a AIRCRAFT ACCIDENT REPORT AND EXECUTIVE SUMMARY Reference: CA18/2/3/9398 Aircraft registration ZU-BBW Date of accident 22 January 2015 Time of accident 0845Z Type of aircraft Bushbaby 450 (Aeroplane) Type of operation Private Pilot-in-command licence type National pilot Age 44 Licence valid Yes Pilot-in-command flying experience Last point of departure Next point of intended landing Total flying hours Hours on type 6,3 Mossel Bay Aerodrome (FAMO), Western Cape Province Mossel Bay Aerodrome (FAMO), Western Cape Province Location of the accident site with reference to easily defined geographical points (GPS readings if possible) 10 m to the left of runway 09 at FAMO (GPS position: South East) Meteorological information Number of people on board Synopsis Surface wind 135 /5 kt, Temperature 24 C, Visibility + 10 km No. of people injured 1 No. of people killed 0 After the pilot had conducted a pre-flight inspection of the aircraft, he boarded the aircraft with the intention to conduct a local private flight over the area and to return to FAMO. He taxied the aircraft to the holding point of runway 09, as he had elected to use this runway for take-off because the prevailing wind at the time was from the southeast. At the holding point he performed engine power checks, which included checking the magnetos, which were satisfactory. He then lined up on the runway and again checked the wind, which was unchanged. As the aircraft accelerated, the tail lifted and the aircraft became airborne at an indicated airspeed of approximately 70 mph. The pilot stated that he kept the wings level, but at a height of approximately 100 feet above the runway surface the left wing suddenly lifted; he then corrected the attitude of the aircraft with opposite control stick input. Then the right wing lifted; this happened twice, and as the right wing lifted again he applied opposite stick and rudder, but it had no effect and the left wing tip impacted the runway surface, which caused the aircraft to swing to the left and impact the ground next to the runway. Available evidence indicate that a cross wind from the right was blowing at the time in access of approximately 10 knots. The pilot suffered a laceration to his lower left leg and both hands and was taken to hospital. Probable cause The left wing of the aircraft impacted with the runway surface following an abrupt change in the attitude of the aircraft during a cross wind take-off with the prevailing wind being from the right. ASP date Release date CA 12-12a 11 JULY 2013 Page 1 of 20

2 Section/division Accident and Incident Investigation Division Form Number: CA 12-12a AIRCRAFT ACCIDENT REPORT Name of Owner : M.C. Meiring Name of Operator : Private Manufacturer : Kitplanes for Africa Model : Bushbaby 450 Nationality : South African Registration Marks : ZU-BBW Place : Mossel Bay Aerodrome Date : 22 January 2015 Time : 0845Z All times given in this report are Co-ordinated Universal Time (UTC) and will be denoted by (Z). South African Standard Time is UTC plus 2 hours. Purpose of the Investigation: In terms of Regulation of the Civil Aviation Regulations (1997) this report was compiled in the interest of the promotion of aviation safety and the reduction of the risk of aviation accidents or incidents and not to establish legal liability. Disclaimer: This report is produced without prejudice to the rights of the CAA, which are reserved. 1. FACTUAL INFORMATION 1.1 History of flight After the pilot had conducted a pre-flight inspection of the aircraft, he boarded the aircraft with the intention to conduct a local private flight over the area and return to FAMO. He taxied the aircraft to the holding point of runway 09, as he had elected to use this runway for take-off because the prevailing wind at the time was from an south-easterly direction At the holding point he performed engine power checks, which included checking the magnetos, which were satisfactory. He then lined up on the runway and again checked the windsock, which indicated the wind to be calm. As the aircraft CA 12-12a 11 JULY 2013 Page 2 of 20

3 accelerated, the tail lifted and the aircraft became airborne at an indicated airspeed of approximately 70 miles per hour (mph) according to the pilot. Once airborne he kept the wings level, but at a height of approximately 100 feet above the runway surface the left wing suddenly lifted; he then corrected the attitude of the aircraft with opposite control stick input. Then the right wing lifted; this happened twice, and as the right wing lifted again he applied opposite stick and rudder, but it had no effect and the left wing tip impacted the runway surface, which caused the aircraft to swing to the left and impact the ground next to the runway in a substantial nosedown attitude, with the aircraft coming to rest in an upright position facing in a south-easterly direction. The pilot suffered a laceration to his lower left leg and both hands and was taken to hospital by an aircraft maintenance engineer (AME) based at the aerodrome, who rushed to the scene with his vehicle and assisted the pilot The accident occurred during daylight conditions at a geographical position determined to be South East at an elevation of 569 feet above mean sea level (AMSL). Threshold runway 09 Figure 1. Google Earth image of the Mossel Bay aerodrome indicating the final position of ZU-BBW CA 12-12a 11 JULY 2013 Page 3 of 20

4 1.2 Injuries to persons Injuries Pilot Crew Pass. Other Fatal Serious Minor None Damage to aircraft The aircraft sustained substantial damage during the impact sequence. Figure 2. The aircraft as it came to rest to the left of runway Other damage No other damage was caused. CA 12-12a 11 JULY 2013 Page 4 of 20

5 1.5 Personnel information Pilot-in-command Nationality South African Gender Male Age 44 Licence number Licence type National pilot Licence valid Yes Type endorsed Yes Ratings None Medical expiry date 31 October 2015 Restrictions None Previous accidents None Flying experience: Total hours Total past 90-days 30.9 Total on type past 90-days 3.9 Total on type The pilot conducted his conversion onto the Bushbaby type aircraft over a period of 9½ months. During this period he flew four flights with a flight instructor; the first flight was on 4 February 2014 and the last flight on 25 November His conversion onto type was conducted via an approved aviation training organisation (ATO), and his logbook was endorsed accordingly The table below contains a summary of the pilot s flying experience on the Bushbaby type aircraft. The information was obtained from the ATO, the pilot s logbook as well as the flight folio of the aircraft ZU-BBW, of which the pilot was the owner. Date Registration Pilot-in-command Duration 4/02/2014 ZU-BJI Type conversion flight with flight instructor /02/2014 ZU-BJI Type conversion flight with flight instructor /10/2014 ZU-BJI Type conversion flight with flight instructor /11/2014 ZU-BJI Type conversion flight with flight instructor /12/2014 ZU-BBW Self /01/2015 ZU-BBW Self /01/2015 ZU-BBW Self (accident flight) Total hours flown on type 6.3 CA 12-12a 11 JULY 2013 Page 5 of 20

6 1.5.4 The pilot mentioned during an interview that during the accident flight he was not wearing shoes, but was flying in his socks. He indicated that during his training onto the aircraft type, a tail dragger, one needed to be responsive/quick on the rudder pedals, and in order to get a better feel on the pedals one needed shoes with very thin soles or fly barefooted or with socks, which he opted to do The pilot was also the owner of a Jabiru type aircraft and had flown most of his hours as a pilot on the Jabiru, which had a fixed tricycle undercarriage (with nose wheel). 1.6 Aircraft Information Airframe: Type Bushbaby 450 Serial number SN-08 Manufacturer Kitplanes for Africa Year of manufacture 1996 Total airframe hours (at time of accident) Last Annual inspection (hours & date) September 2014 Hours since last Annual inspection 2.3 Authority to Fly (issue date) 7 October 2014 Authority for Fly (expiry date) 18 September 2015 C of R (issue date) (present owner) 27 August 2014 Operating categories Private According to the accident and incident investigation database, the aircraft was involved in a previous accident on 21 April 2000 when the engine failed in flight near the Albert Falls Dam in KwaZulu-Natal. The pilot was unable to restart the engine and executed a forced landing in an orange orchard, which resulted in substantial damage to the aircraft. According to available information (page 6 of the aircraft logbook), the aircraft was involved in a hard landing incident on 14 August 2010, during which the right main landing gear strut was bent. Following the incident the undercarriage was replaced and the landing gear configuration was converted from a fixed tricycle gear (with nose wheel) to a tail dragger. It was the decision of the new owner of the aircraft to reconfigure the undercarriage to a tail dragger, as he wanted to gain experience in CA 12-12a 11 JULY 2013 Page 6 of 20

7 flying a tail dragger type aircraft. The table on the next page contains a summary of the aircraft s flying hours since the annual inspection was certified on 19 September 2014 until the last flight prior to the accident flight on 22 January The information was acquired from the aircraft flight folio. The aircraft was flown on both days prior to the accident flight. The pilot who flew it the day before the accident flight was interviewed and indicated that the aircraft was airworthy during the flight. Date Journey Duration 11/12/2014 Local flight from FAMO back to FAMO 1.2 7/01/2015 Local flight from FAMO back to FAMO /01/2015 Local flight from FAMO back to FAMO /01/2015 Local flight from FAMO back to FAMO 0.3 Total hours flown since Annual Inspection 2.3 Engine: Type Rotax 912 UL Serial number Hours since new Hours since overhaul TBO not yet reached Propeller: Type Warp Drive Serial number Unknown Hours since new 52.3 Hours since overhaul TBO not yet reached The propeller listed above was fitted to the aircraft during the last Annual inspection (certified on 19 September 2014). The propeller had been in operation for 50 hours prior to it being installed on this aircraft. Weight and balance The aircraft was weighed on 19 September 2014 and the empty weight was calculated to be kilograms (kg). This weight included unusable fuel as well as engine oil. CA 12-12a 11 JULY 2013 Page 7 of 20

8 The pilot was the sole occupant on board the aircraft and weighed 98 kg. The fuel state according to him was 50 litres (36 kg) on take-off. The take-off weight was found to be within the operating limits of the aircraft, with the maximum take-off weight not allowed to exceed 450 kg. 1.7 Meteorological information The weather information table below was acquired from the pilot s questionnaire. Wind direction 135 Wind speed 5 knots Visibility + 10 km Temperature 24 C Cloud cover Clear Cloud base Clear Dew point Unknown Meteorological Aeronautical Report (METAR) There was no weather station at FAMO and therefore no official weather data was available for the aerodrome. The closest licensed aerodrome to FAMO that had an official weather office and for which a METAR was available for that time was George Aerodrome (FAGG), which is located 18.5 nm (34 km) to the northeast of FAMO. (All wind directions issued by the South African Weather Services are reflected in True North) FAGG Z VRB04KT 9999 FEW008 24/18 Q1018= Time Z Wind - Variable 4 knots Visibility m Cloud cover - Few (1 to 2 octas) at 800 feet Temperature - 24 C Dew point - 18 C Barometric pressure hpa (hectopascal) FAGG Z 21007KT 180V FEW008 25/20 Q1018= Time Z Wind /7 knots, variable between CA 12-12a 11 JULY 2013 Page 8 of 20

9 Visibility m Cloud cover - Few (1-2 octas) at 800 feet Temperature - 25 C Dew point - 20 C Barometric pressure hpa (hectopascal) Wind assessment after the accident The photo below was taken approximately 20 minutes after the accident occurred by a person who was at the aerodrome at the time and went to the scene. The windsock, which is visible in Figure 3, indicates the prevailing wind to be from the right of runway 09, approximately 90 to the runway heading (crosswind) at approximately 10 knots. Figure 4 on the next page is an enlargement of the same photo to illustrate the windsock orientation. Windsock indicating a cross wind from the right. Runway Figure 3. A view of the windsock in relation to the runway and the wreckage CA 12-12a 11 JULY 2013 Page 9 of 20

10 Windsock Figure 4. A photo of the windsock in relation to the wreckage 1.8 Aids to navigation The aircraft was equipped with basic navigational aids required to conduct the flight. 1.9 Communication FAMO is an unmanned aerodrome facility; the pilot broadcast his intentions on the designated aerodrome frequency of MHz. CA 12-12a 11 JULY 2013 Page 10 of 20

11 1.10 Aerodrome information Aerodrome location 4 nm WNW of Mossel Bay town Aerodrome co-ordinates South East Aerodrome elevation 562 feet above mean sea level (AMSL) Runway designations 09/27 Runway dimensions 1126 m x 18 m Runway used 09 Runway surface Asphalt Approach facilities Runway lights Aerodrome status Licensed Air traffic control service No 1.11 Flight recorders The aircraft was not equipped with a flight data recorder (FDR) or a cockpit voice recorder (CVR), nor was it required by the regulations to be fitted to this type of aircraft Wreckage and impact information The left wing tip of the aircraft impacted the asphalt runway surface approximately 332 m from the threshold of runway 09 and 5 m from the runway edge to the left of the runway centreline, leaving a scrape mark approximately 4 m in length on the runway surface. The aircraft came to rest approximately 10 m to the left of the runway edge in an upright position, right wing low, facing in a south-easterly direction, which was 90 opposite to the direction of take-off. CA 12-12a 11 JULY 2013 Page 11 of 20

12 Figure 5. Scrape mark visible on the runway surface caused by the left wing tip Figure 6. Damage to the left wing tip following runway surface contact CA 12-12a 11 JULY 2013 Page 12 of 20

13 The left wing contact with the runway surface caused the aircraft to cartwheel and impact the ground to the left of the runway edge in a substantial nose-down attitude, as was evident from the deformation caused to the spinner, propeller, engine and forward structure of the aircraft, including the cockpit/cabin area and the main undercarriage (being a tail dragger). One of the propeller blades separated from the propeller hub on impact and a second blade, visible in Figure 7, fractured in close proximity to the root. Both carburettor bowls were removed during the on-site investigation and both still contained fuel, as can be seen in Figures 8 and 9 respectively. The right-wing tank still contained a substantial amount of fuel, as the tank remained intact. The pilot stated in an interview that the engine delivered full power during take-off and no engine-related malfunction was encountered during the flight. Figure 7. Damage to the spinner and propeller CA 12-12a 11 JULY 2013 Page 13 of 20

14 Carburettor bowl still contained some fuel. Figure 8. Photo of the fuel content in the right-hand carburettor bowl Carburettor bowl still contained some fuel. Figure 9. Photo of the fuel content in the left-hand carburettor bowl CA 12-12a 11 JULY 2013 Page 14 of 20

15 Both main wheels bent outwards; the tail wheel remained intact and undamaged. The right wing tip sustained damage, with the outer section of the canvas being torn. The aft fuselage and empennage sustained minor damage. A detailed inspection was performed of the flight controls and continuity was determined throughout the system. Impact damage did cause some distortion in the area of the cockpit/cabin area, with substantial deformation being evident in the area of the rudder pedals and floor structure. The flaperon linkage on the left wing separated from the wing attachment during the impact sequence. The right-wing linkage remained secured to the flaperon, but displayed distortion due to impact. Both rudder cables were found to be intact and secured at both ends (rudder pedal as well as the rudder control surface end). (a) Figure 9. Left wing flaperon linkage that separated from the wing (a); and right wing flaperon still intact but distorted (b) (b) (a) Figure 10. Photo of right rudder cable still attached to the rudder (a); as well as the left rudder cable still attached (b) (b) CA 12-12a 11 JULY 2013 Page 15 of 20

16 1.13 Medical and pathological information Not applicable Fire There was no evidence of a pre- or post-impact fire Survival aspects The accident was survivable, although the cockpit/cabin area was substantially deformed when the aircraft impacted the ground in a substantial nose-down attitude. The pilot sustained a laceration to his lower left leg and both hands. He was making use of the aircraft-equipped four point safety harness Bystanders at the aerodrome rushed to the scene of the accident in aid of the pilot. An aircraft maintenance engineer (AME) working at the aerodrome responded to the accident scene with his vehicle, and he took the pilot to a private hospital in Mossel Bay where he received medical treatment Tests and research None was considered necessary Organisational and management information This was a private flight, with the pilot also being the owner of the aircraft The Approved Person (AP) No. 336 who certified the last Annual Inspection on the aircraft prior to the accident flight was in possession of a valid AP approval that was issued by the Aero Club of South Africa. CA 12-12a 11 JULY 2013 Page 16 of 20

17 1.18 Additional information Crosswind limitation The aircraft crosswind component limit, according to the aircraft manufacturer, was 12 knots. However, there was no official pilot s operating handbook (POH) to support this figure. This aircraft being one of the first aircraft manufactured of its kind (serial number 8) in South Africa, no standard POH was available at the time. The 12 knot crosswind value was incorporated into the standard POH for aircraft of this type, which followed several years after the aircraft in question was manufactured. The illustration below sets out the procedure to be followed during a crosswind take-off. Figure 11. Illustration of crosswind take-off technique 1.19 Useful or effective investigation techniques No new methods were applied. CA 12-12a 11 JULY 2013 Page 17 of 20

18 2. ANALYSIS 2.1 Man (Pilot) The pilot was the holder of a valid National pilot s licence. He had conducted his conversion onto the Bushbaby type aircraft via an approved ATO over a period of 9½ months. During this period he flew 4.6 hours on the aircraft type. Subsequent to the aircraft type being endorsed in his logbook, he conducted two solo flights with the aircraft ZU-BBW, which amounted to 1.7 hours of flight time. The accident flight would have been the pilot s third solo flight on type. The pilot had flown many hours on the Jabiru type aircraft, which was equipped with a fixed tricycle landing gear (nose wheel) instead of the tail wheel configuration of the Bushbaby. The take-off and landing technique with a tail wheel equipped aircraft differs from that of a conventional tricycle undercarriage aircraft, as the tail of the aircraft needs to lift as the aircraft accelerates during the take-off roll and needs to be lowered again during the landing phase. The pilot states that he was airborne off runway 09 and was at a height of approximately 100 feet AGL when he experienced a sudden wing lift from the left and then to the right. This phenomenon repeated itself twice, but he was unable to gain control of the aircraft before the left wing made contact with the runway surface. The pilot further stated in an interview that he did not encounter any engine power related malfunction during the duration of the flight. Inspection of the aircraft revealed that flight control continuity was not compromised. The failure of the left wing flaperon linkage was associated with the left wing impacting the runway surface. All other control linkages, control rods and cables were intact and secured, which eliminates the possibility of a control failure in flight that could have contributed or have caused the accident. The pilot who flew the aircraft the day prior to the accident flight was also interviewed, and he indicated that the aircraft was serviceable during the flight. No official weather data was available for FAMO. The pilot indicated in his questionnaire that the wind on take-off was from the southeast (135 ) at 5 knots, with FAGG weather data indicating the wind to be variable between 180 and 270 during the time of the accident. However, FAGG was some 18.5 nm away. Photographic evidence of the wreckage, windsock and runway that was taken approximately 20 minutes after the accident indicates a crosswind from the right on CA 12-12a 11 JULY 2013 Page 18 of 20

19 runway 09. The pilot did not indicate that he applied any crosswind take-off technique, even though he had assessed the wind to be from the right prior to takeoff. The possibility that the aircraft may have encountered a sudden gust of wind or a whirlwind shortly after take-off resulting in the sudden abrupt change in the attitude of the aircraft that caught the pilot off guard could therefore not be ruled out. 2.2 Machine (Aircraft) The pilot indicated that the engine produced power during the flight. This observation was consistent with the damage to the propeller. There was ample fuel on board the aircraft, which was of the correct grade and free of contamination. Damage to the aircraft was consistent with the impact sequence. A detailed inspection of the flight controls revealed that continuity was not compromised and all flight controls were accounted for. 2.3 Environment The pilot indicated that he assessed the wind to be from the southeast at 5 knots before take-off. A photograph that was taken approximately 20 minutes after the accident occurred by a person who responded to the accident scene bears out the pilots observation of a possible variation in wind strength and direction and indicate the wind to be at approximately 10 knots from the right, when referring to Figure 4 on page 10 of this report. The possibility that a sudden change in wind conditions occurred during this period was highly improbable. 3. CONCLUSION 3.1 Findings The pilot was the holder of a valid National pilot s license and had the aircraft type endorsed in his logbook He had concluded his conversion onto the Bushbaby type aircraft on 25 November During the 9½ month period he had flown 4.6 hours in four flights According to the available information the pilot had flown a total of 6.3 hours on the Bushbaby aircraft type when the accident occurred The aircraft was in possession of a valid Authority to Fly. CA 12-12a 11 JULY 2013 Page 19 of 20

20 3.1.5 The take-off weight was found to be within the operating limitations of the aircraft, with the pilot being the sole occupant The pilot stated that the engine was delivering full power and the fuel quantity was 50 litres prior to take-off Damage to the aircraft was consistent with the impact sequence Flight control continuity was not compromised Crosswind conditions (from the right) prevailed during take-off. Photographic evidence that was taken approximately 20 minutes after the accident indicates the wind to be a cross wind from the right at approximately 10 knots. 3.2 Probable cause The left wing of the aircraft impacted with the runway surface following an abrupt change in the attitude of the aircraft during a cross wind take-off with the prevailing wind being from the right. 4. SAFETY RECOMMENDATIONS 4.1 None. 5. APPENDICES 5.1 None. CA 12-12a 11 JULY 2013 Page 20 of 20