AIRCRAFT ACCIDENT REPORT AND EXECUTIVE SUMMARY

Transcription

1 Section/division Accident and Incident Investigations Division Form Number: CA 12-12a AIRCRAFT ACCIDENT REPORT AND EXECUTIVE SUMMARY Aircraft Registration Type of Aircraft Reference: CA18/2/3/9424 ZU-DOU Date of Accident 14 March 2015 Time of Accident 0430Z North Wing 582 Trike (Microlight) Type of Operation Private Pilot-in-command Licence Type National Pilot Age 36 Licence Valid Yes Pilot-in-command Flying Experience Last point of departure Next point of intended landing Total Flying Hours Microland Flight Park (FABA) Gauteng Microland Flight Park (FABA) Gauteng 53.3 Hours on Type 9 Location of the accident site with reference to easily defined geographical points (GPS readings if possible) Bapsfontein airfield at GPS co-ordinates as: S ', E ' and a field elevation of 5476ft AMSL Meteorological Information Number of people on board Synopsis Wind direction: 35º at 8kt, Air temp: 17º C, Dew point: 21ºC, Visibility: CAVOK 1+1 No. of people injured 1+1 No. of people killed 0 The pilot accompanied by a passenger took off from Bapsfontein for a private flight. The pilot stated that he stalled the microlight during take-off. The microlight landed onto some vegetation around the airfield. The aircraft sustained substantial damages during the accident sequence whereby the pilot and his passenger experienced minor injuries. The investigation revealed that the cause of the accident was lack of control of the aircraft configuration due to insufficient operational experience on the aircraft type. Probable Cause The pilot stalled the aircraft during take-off due to lack of experience on taking off with extra load on carriage on the aircraft type. IARC Date Release Date CA 12-12a 11 JULY 2013 Page 1 of 14

2 Section/division Accident and Incident Investigation Division Form Number: CA 12-12a AIRCRAFT ACCIDENT REPORT Name of Owner : Becker M Name of Operator : Becker M Manufacturer Model Nationality Registration Marks Place Date : 14 March 2015 Time : 04:30Z : NORTHWING Design USA : ASM 582E : South African : ZU-DOU : Benoni, Crystal Park at Microland Flight Park 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 The pilot was intending to conduct a private flight accompanied by a passenger around the airfield general flying area. The pilot stated that during take-off, the aircraft stalled and crash landed into the crop field. The microlight sustained substantial damages. The pilot and passenger were injured during the sequence of the accident. CA 12-12a 11 JULY 2013 Page 2 of 14

3 1.1.2 The aircraft accident occurred in daylight conditions (VMC) visual meteorological conditions on a place with GPS co-ordinates as: S ', E ' and a field elevation of 5476ft AMSL (above mean sea level) 1.2 Injuries to Persons The pilot and passenger sustained minor injuries Injuries Pilot Crew Pass. Other Fatal Serious Minor None Damage to Aircraft The aircraft sustained substantial damage Figure 1: Shows the microlight after the accident CA 12-12a 11 JULY 2013 Page 3 of 14

4 1.4 Other Damage The microlight crashed into the crop field damaging the maize vegetation. 1.5 Personnel Information Nationality South African Gender Male Age 35 Licence Number Licence Type NPL Licence valid Yes Type Endorsed Yes Ratings Weight Shift Controlled Microlight Medical Expiry Date 31 May 2018 Restrictions None Previous Accidents None Flying Experience: Total Hours 53.3 Total Past 90 Days 9 Total on Type Past 90 Days 9 Total on Type The pilot was also the owner of the microlight. The pilot prior to flying solo did a conversion of 2 hours over 2 days whereby he flew only once with an instructor for 1 hour. The pilot prior to the accident flight attained a total of 9 flying hours with the aircraft type whereby 8 hours were as a solo operator According to the pilot flying records, he conducted his training on a different trike design from the accident aircraft. Aircraft type features Windlass Apache Wing Span 10.5m 9.5 Empty weight 150 kg kg Maximum load 330 kg 450 kg Best angle climb 30º 30º Never exceed 13kph 50kph Stall with full load 52 kph 33kph CA 12-12a 11 JULY 2013 Page 4 of 14

5 1.6 Aircraft Information Airframe: Information was extracted from: FAA Weight-Shift Control Aircraft (WSC) is a single- and two-place trikes that do not meet the criteria of an ultralight vehicle but do meet the criteria of LSA. Flight control of the aircraft depends on the wing s ability to flexibly deform rather than on the use of control surfaces. Weight-shift control (WSC) aircraft means a powered aircraft with a framed pivoting wing and a fuselage controllable only in pitch and roll by the pilot s ability to change the aircraft s center of gravity (CG) with respect to the wing. Flight control of the aircraft depends on the wing s ability to deform flexibly rather than on the use of control surfaces. Type ASM 582E Serial Number Manufacturer North wind Design USA Date of Manufacture 2004 Total Airframe Hours (At time of Accident) Last MPI (Date & Hours) 21 January Hours since Last MPI 7.8 C of ATF (Issue Date) 22 January 2015 C of ATF (Expiry Date) 20 January 2016 C of R (Issue Date) (Present owner) 19 January 2015 Operating Categories NTCA Engine: Type Rotax 582 Serial Number Hours since New Hours since Overhaul TBO not yet reached Propeller: CA 12-12a 11 JULY 2013 Page 5 of 14

6 Type Aero (X3) Serial Number 5816, 5817, 5818 Hours since New Hours since Overhaul TBO not yet reached There are several unique features of the Weight Shift Controlled (WSC) aircraft: Different wings can be put on a single carriage. This allows the pilot to have a large wing that can take off in short distances, which would be good for low and slow flying. A large wing with a lightweight carriage can also be used for soaring and is capable of flying at speeds below 30 miles per hour (mph). At the other extreme, a smaller high performance wing can be used for flying long distances at high speeds. With a small wing and a larger motor, WSC aircraft can fly at speeds up to 100 mph. Figure 2: Shows the weight shift controlled aircraft Since the WSC aircraft is designed without the weight and drag of a tail, the performance is significantly increased. The aircraft can take off and land in short fields, has good climb rates, can handle a large payload, has a good glide ratio, and is fuel efficient. The WSC LSA typically can carry 600 pounds of people, fuel, and CA 12-12a 11 JULY 2013 Page 6 of 14

7 baggage. There were no mass and balance calculations done for the flight. The aircraft type has a maximum permissible mass of 450kg (992lbs). The pilot and his passenger had a mass of 83kg(182.98lbs) and 110kg(242.5lbs) with a fuel of approximately 35liters(55lbs). All this added to a total mass of lbs and was carried during the aircraft take-off. The aircraft has an empty mass of 222.8kg (491.18lbs). The aircraft had a total take-off mass of lbs. The aircraft mass was within limits by -20lbs. Information obtained from North Wing S-LSA Pilot Operating Handbook page 12 Center of Gravity Limits Center of gravity limits are not critical on a trike (flex wing aircraft). Having the trike carriage attached to the wing at a single point (tether point) with a universal bracket, variations in weight in the cockpit or fuel loading cannot influence the aircraft balance. The weight loading in the trike only has an effect on the angle of attack at which the trike moves through the air. The range that you can move the trike forwards or back on the keel of the wing is 50½ to 52½. Operating Weight Limits Max. take-off weight 990 lbs Wet trike weight (with gal fuel) 550 lbs Empty Weight w/fairing 480 lbs wo/fairing 450 lbs Front seat load range: lbs Rear seat load range: lbs Total max crew weight w/full fuel 440 lbs Sport X2/ Apache Total max crew weight w/full fuel 460 lbs Sport X2 NOTE: Max crew weight can change depending if the trike is full of fuel. NOTE: Minimum flight crew is 1 person (Front Seat). Maximum crew is 2 persons. The aircraft must be maintained properly by the aircraft owner or other qualified personnel and have the aircraft logbooks available for inspection. Dual flight controls are required in two-seat aircraft used for training. The carriage is comprised of the engine and flight deck attached by a structure to wheels, floats, or skis; it may also be referred to as the fuselage. The wing is the sail, structure that supports the sail, battens (ribs) that form the airfoil, and associated hardware Aircraft documentation maintenance records, certificates and service bulletin CA 12-12a 11 JULY 2013 Page 7 of 14

8 letters were studied and reviewed. According to these, the aircraft had been equipped and maintained according to existing regulations. All service bulletins published by the engine and helicopter manufacturers had been adhered to and complied with by both the owner and the approved personnel (AP). 1.7 Meteorological Information The meteorological information as obtained from the South African weather Service website. Wind direction 35º Wind speed 08 kts Visibility CAVOK Temperature 17ºC Cloud cover 0/8 Cloud base None Dew point 12 ºC 1.8 Aids to Navigation The microlight was equipped with the standard factory-fitted navigational equipment approved by the Regulator. There were no recorded defects to navigational equipment prior to the flight. 1.9 Communications The microlight was equipped with one VHF (Very High Frequency) radio approved by the Regulator. There were no recorded defects regarding the communication equipment prior to the flight Aerodrome Information The airfield is an unmanned with limited operation activities. It is equipped with a gravel runway and is situated around the farming area. CA 12-12a 11 JULY 2013 Page 8 of 14

9 Figure 3: Shows the area FABA aerodrome Aerodrome Location Bapsfontein, Benoni, Gauteng Aerodrome Co-ordinates S ', E ' Aerodrome Elevation 5476 ft Runway Designations 02/20 Runway Dimensions 1188m 40m Runway Used 02 Runway Surface Grass Approach Facilities None 1.11 Flight Recorders The microlight was not equipped with a flight data recorder or a cockpit voice recorder. Neither recorder was required by the relevant aviation regulations Wreckage and Impact Information The aircraft impact was on the crop field. CA 12-12a 11 JULY 2013 Page 9 of 14

10 During take-off the microlight stalled with the left hand side wing resulting with a banking attitude towards the left hand side. The microlight impacted with the vegetation and sustained substantial damages Medical and Pathological Information The injury assessment came with the conclusion that no medical attentions require after the accident as the occupants sustained minor injuries Fire There was no post or pre-impact fire during the accident sequence 1.15 Survival Aspects The aircraft accident was considered survivable. Due to the height and the attitude at which the aircraft stalled and impacted the ground, the occupants sustained minor any injuries during the accident sequence. The aircraft is equipped with shoulder harness which the pilot and his passenger were making use and prevented them from sustaining minor injuries during the accident sequence Tests and Research Take Off and Initial Climb The initial take off roll can be performed with the base tube in the fully extended position or in the trim position. Until you become familiar with your trike, it is usually better to start with the bar in the fully extended position. This will lift the trike off the ground as soon as it achieves flying speed and will minimize the stresses on the trike during the ground roll. This is especially true on rough or grass runways. Do NOT use this technique for cross wind take-offs as these require greater lift off speed to overcome any turbulence or loss of lift at the critical lift off point. CA 12-12a 11 JULY 2013 Page 10 of 14

11 When starting from the fully extended position Apply full power using foot throttle only while holding the base tube against the front compression strut (nose tube) When the nose wheel lifts off the ground, smoothly, but without hesitation, bring the base tube back until it is about 2 behind the normal trim position. This will provide a little excess speed in case of an engine out while close to the ground. Keep the base tube behind the trim position (faster) until an altitude of at least 300 feet AGL is achieved. At that point, the base tube can go to trim and the engine power can be slightly reduced. Continue climbing at trim position to the desired altitude staying within glide distance of an emergency landing site. NOTE! This may require staying near the airport until sufficient altitude is achieved to leave the field pattern. On initial climb out where engine failure is most dangerous, do not pitch the nose up more than 45 degrees. Very steep climbs are dangerous and cause a full stall followed by rapid pitch down moment especially if the engine quits. **** Never operate your trike where you leave yourself no option to bailout to a safe landing area if your engine were to stop or any other mechanical failure. Research Stalls: Exceeding the Critical AOA As the AOA increases to large values on the wing chord, the air separates starting at the back of the airfoil. As the AOA increases, the separated air moves forward towards the leading edge. The critical AOA is the point at which the wing is totally stalled, producing no lift regardless of airspeed, flight attitude, or weight. Because the AOA of the WSC wing root chord/nose is so much higher than the AOA of the tips, the nose stalls before the tips. It is similar to stalling with the airplane canard in which the nose stalls first, the main wing (or tips for the WSC aircraft) continues to CA 12-12a 11 JULY 2013 Page 11 of 14

12 fly, and the nose drops due to lack of lift. In most normal situations, the root chord/nose stalls first because it is at a much higher AOA. The tips continue to fly, making the WSC wing resistant to a complete wing stall. A pilot can even bring the aircraft into a high pitch angle stall attitude and keep the nose high. The nose stalls and rotates down because of the loss of lift, while the tips keep flying and maintain control of the aircraft. If flying within the operating limitations of the aircraft and the WSC reaches a high AOA, the nose stalls, but the tips continue flying. However, it must be understood that there are many wing designs with many types of stall characteristics for each unique design. For example, high-performance wings could have less twist to gain performance, which could cause the wing to stall more abruptly than a training wing with more twist Organizational and Management Information This was a private flight The aircraft was maintained and equipped by approved personnel. The last annual maintenance inspection was conducted on 21 January Additional Information The pilot stated that the additional weight of the passenger was caused the aircraft to stall During investigation the pilot stated that he could not conduct the mass and balance calculation during the accident flight as he believes that the WSC is not a fixed wing type of an aircraft. He also stated that the WSC is not equipped with a load sheet Useful or Effective Investigation Techniques None CA 12-12a 11 JULY 2013 Page 12 of 14

13 2. ANALYSIS 2.1 The pilot was license and qualified in accordance with existing regulatory procedures. He was medically fit for the flight with a valid medical certificate expiring on 31 May The pilot had a total of 53.3 flying hours out of which 9 hours was accumulated on the accident aircraft type. The aircraft was endorsed on the pilot s license. Although the pilot was qualified on microlight aircraft, his experience on the aircraft type was insufficient. The pilot has during his training flown a different microlight aircraft type. 2.3 The pilot stated that he stalled the aircraft during take-off due to extra weight (passenger) who was accompanying him. Although the mass calculation was not done during a pre-flight, a considerable calculation was conducted during investigation. The findings where that the aircraft s mass was within limits during take-off, however the pilot during take-off lost control while climbing due to lack of experience in flying with an extra weight on the aircraft type resulting with him experiencing difficulties in controlling the keel control to maintain a desired angle of attack during climb when the aircraft move through the air. The unstable pendulum weight shifting during unstable may have exceed the aircraft type operational limits. The investigation also considered the pilot s aircraft conversion and operation duration. The pilot been the owner of the aircraft had accumulated 9 flying hours over a period of 3 months whereby 8hour was accumulated as a solo operator. This also shows that the pilot s knowledge on the aircraft familiarisation was insufficient more especially in carrying an extra weight, the pilot how flew once with an instructor with aircraft type for one hour aircraft conversion. 2.4 The pilot informed the investigating team that the he could not do the mass and balance calculation because the aircraft was not a fixed wing and also it was not equipped with a load sheet. However the aircraft documents indicated that the aircraft has a maximum permissible mass of 450 kg (600lbs). This raised a concern regarding the pilot s safety operations in aviation more especially for the general aviation training in general. CA 12-12a 11 JULY 2013 Page 13 of 14

14 2.5 Fine weather conditions prevailed in the area of the accident site and weather was not considered a contributing factor to the accident. 2.6 According to the maintenance records, the aircraft was maintained and equipped in accordance with the existing regulatory approved procedures. The last maintenance that was conducted on an aircraft was on 21 January 2015 at airframe hours. 3. CONCLUSION 3.1 Findings The aircraft was maintained and equipped in accordance with regulatory procedures The pilot was license for the flight but did not have sufficient experience of operation on the aircraft type There was no mass calculation conducted for the flight, however the investigation revealed that the aircraft was within limits during take-off The weather was not considered a contributing factor to the accident. 3.2 Probable Cause/s 3.2 The pilot stalled the aircraft during take-off due to lack of experience on taking off with extra load on carriage on the aircraft type. 4. SAFETY RECOMMENDATIONS 4.1 None 5. APPENDICES 5.1 None CA 12-12a 11 JULY 2013 Page 14 of 14