Crash of an Antonov AN-26B in Omega

Date & Time: Nov 30, 2013
Type of aircraft:
Registration:
NAF-3-642
Flight Type:
Survivors:
Yes
Schedule:
Windhoek - Omega AFB
MSN:
144 01
YOM:
1985
Country:
Region:
Crew on board:
6
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
0
Circumstances:
The aircraft departed Windhoek on a special flight to the disused Airfield of Omega (ex airbase), carrying six crew members and various equipment in order to collect the bodies of all 33 people who have been killed in the crash of the LAM Embraer ERJ-190AR C9-EMC that occurred in the Bwabwata National Park the previous day. The aircraft landed too far down the airstrip that was overgrown by grass and bushes. Unable to stop within the remaining distance, the aircraft overran and collided with trees, causing severe damages to the wings (the right wing was partially torn off). All six occupants escaped unhurt while the aircraft was damaged beyond repair. Hulk still in situ in FEB2014 and may be disassembled and trucked back to Windhoek.
Probable cause:
Wrong landing configuration. Disused airport and runway in poor condition.

Crash of a Cessna 208B Grand Caravan in Saint Mary's: 4 killed

Date & Time: Nov 29, 2013 at 1824 LT
Type of aircraft:
Operator:
Registration:
N12373
Survivors:
Yes
Schedule:
Bethel - Mountain Village - Saint Mary's
MSN:
208B-0697
YOM:
1998
Flight number:
ERR1453
Crew on board:
1
Crew fatalities:
Pax on board:
9
Pax fatalities:
Other fatalities:
Total fatalities:
4
Captain / Total flying hours:
25000
Captain / Total hours on type:
1800.00
Aircraft flight hours:
12653
Circumstances:
The scheduled commuter flight departed 40 minutes late for a two-stop flight. During the first leg of the night visual flight rules (VFR) flight, weather at the first destination airport deteriorated, so the pilot diverted to the second destination airport. The pilot requested and received a special VFR clearance from an air route traffic controller into the diversion airport area. Review of automatic dependent surveillance-broadcast data transmitted by the airplane showed that, after the clearance was issued, the airplane's track changed and proceeded in a direct line to the diversion airport. Postaccident examination of the pilot's radio showed that his audio panel was selected to the air route traffic control (ARTCC) frequency rather than the destination airport frequency; therefore, although the pilot attempted to activate the pilot-controlled lighting at the destination airport, as heard on the ARTCC frequency, it did not activate. Further, witnesses on the ground at St. Mary's reported that the airport lighting system was not activated when they saw the accident airplane fly over, and then proceed away from the airport. Witnesses in the area described the weather at the airport as deteriorating with fog and ice. About 1 mile from the runway, the airplane began to descend, followed by a descending right turn and controlled flight into terrain. The pilot appeared to be in control of the airplane up to the point of the right descending turn. Given the lack of runway lighting, the restricted visibility due to fog, and the witness statements, the pilot likely lost situational awareness of the airplane's geographic position, which led to his subsequent controlled flight into terrain. After the airplane proceeded away from the airport, the witnesses attempted to contact the pilot by radio. When the pilot did not respond, they accessed the company's flight tracking software and noted that the airplane's last reported position was in the area of the airplane's observed flightpath. They proceeded to search the area where they believed the airplane was located and found the airplane about 1 hour later. Postaccident examination of the airframe and engine revealed no mechanical malfunctions or anomalies that would have precluded normal operation. About 3/4 inch of ice was noted on the nonprotected surfaces of the empennage. However, ice formation on the airplane's inflatable leading edge de-ice boots was consistent with normal operation of the de-ice system, and structural icing likely was not a factor in the accident. According to the company's General Operations Manual (GOM), operational control was held by the flight coordinator for the accident flight, and the flight coordinator and pilot-in-command (PIC) were jointly responsible for preflight planning, flight delay, and release of the flight, which included the risk assessment process. The flight coordinator assigned the flight a risk level of 2 (on a scale of 1 to 4) due to instrument meteorological and night conditions and contaminated runways at both of the destination airports. The first flight coordinator assigned another flight coordinator to create the manifest, which listed eight passengers and a risk assessment level of 2. According to company risk assessment and operational control procedures, a risk level of 2 required a discussion between the PIC and flight coordinator about the risks involved. However, the flight coordinators did not discuss with the pilot the risks and weather conditions associated with the flight. Neither of the flight coordinators working the flight had received company training on the risk assessment program. At the time of the accident, no signoff was required for flight coordinators or pilots on the risk assessment form, and the form was not integrated into the company manuals. A review of Federal Aviation Administration (FAA) surveillance activities revealed that aviation safety inspectors had performed numerous operational control inspections and repeatedly noted deficiencies within the company's training, risk management, and operational control procedures. Enforcement Information System records indicated that FAA inspectors observed multiple incidences of the operator's noncompliance related to flight operations and that they opened investigations; however, the investigations were closed after only administrative action had been taken. Therefore, although FAA inspectors were providing surveillance and noting discrepancies within the company's procedures and processes, the FAA did not hold the operator sufficiently accountable for correcting the types of operational deficiencies evident in this accident, such as the operator's failure to comply with its operations specifications, operations training manual, and GOM and applicable federal regulations.
Probable cause:
The pilot's decision to initiate a visual flight rules approach into an area of instrument meteorological conditions at night and the flight coordinators' release of the flight without discussing the risks with the pilot, which resulted in the pilot experiencing a loss of situational awareness and subsequent controlled flight into terrain. Contributing to the accident were the operator's inadequate procedures for operational control and flight release and its inadequate training and oversight of operational control personnel. Also contributing to the accident was the Federal Aviation Administration's failure to hold the operator accountable for correcting known operational deficiencies and ensuring compliance with its operational control procedures.
Final Report:

Crash of a Boeing 737-53A in Kazan: 50 killed

Date & Time: Nov 17, 2013 at 1924 LT
Type of aircraft:
Operator:
Registration:
VQ-BBN
Survivors:
No
Schedule:
Moscow - Kazan
MSN:
24785/1882
YOM:
1990
Flight number:
TAK363
Country:
Region:
Crew on board:
6
Crew fatalities:
Pax on board:
44
Pax fatalities:
Other fatalities:
Total fatalities:
50
Captain / Total flying hours:
2783
Captain / Total hours on type:
2509.00
Copilot / Total flying hours:
2093
Copilot / Total hours on type:
1943
Aircraft flight hours:
51547
Aircraft flight cycles:
36596
Circumstances:
On final approach to Kazan from Domodedovo in marginal weather conditions, crew was forced to make a go around as the aircraft was not correctly aligned with the runway centerline. While climbing to a height of 700 meters, the aircraft went out of control, nosed down and hit the ground. The aircraft disintegrated on impact and all 50 occupants were killed. MAK reported in a first statement that the crew did not follow the standard approach profile and the approach was unstable. TOGA mode was selected, autopilot deactivated and flaps raised from 30 to 15 degrees. As gear were retracted, the aircraft pitched up to about 25 degrees nose up and the indicated airspeed decreased from 150 to 125 knots. Crew countered the nose up by control inputs and the climb was stopped. Aircraft reached a maximum height of 2,300 feet and began to rapidly descend until it impacted the ground with a near vertical angle of 75 degrees at a speed of 242 knots, some 20 seconds after reaching the height of 2,300 feet. The crash was no survivable.
Probable cause:
Systemic weaknesses in identifying and controlling the levels of risk, non-functional safety management system in the airline and lack of control over the level of crew training by aviation authorities at all levels (Tatarstan Civil Aviation Authority, Russian Civil Aviation Authority), that resulted in an unqualified crew being assigned to the flight.
During the go-around the crew did not recognize that the autopilot had disconnected resulting in the aircraft impacting ground in a complex spatial position (nose up upset). The captain, pilot flying, lacked the skills to recover the aircraft from the complex spatial upset (lack of Upset Recovery), that led to significant negative G-forces, loss of spatial orientation sending the aircraft into a steep drive (75 degrees nose down) until impact with ground.
The go around was required because the aircraft on its final approach arrived in a position from which landing was impossible as result of a map shift by about 4000 meters (aircraft systems determining the position of the aircraft in error), the inability of the crew in those circumstances to combine aircraft control and navigation with needed precision, and the lack of active support by air traffic control during prolonged observation of significant deviation from the approach procedure.
The following factors were considered as contributory:
The captain not having had primary flight training,
The flight crew members being allowed to upgrade to Boeing 737 without satisfying the required qualifications including the English language,
Methodical shortcomings in retraining as well as verification of results and quality of training,
Insufficient level of organisation of flight operations at the airline, which resulted in failure to detect and correct shortcomings in working with the navigation equipment, pilot technique and crew interaction, including missed approaches,
Systematic violation of crew work and rest hours, a large debt of holidays, which could have resulted in accumulation of fatigue adversely affecting crew performance, Simulator training that lacked a missed approach with intermediate height and all engines operating,
Increased emotional stress to the flight crew before deciding to go around because they could not establish the position of their aircraft with the necessary precision to accomplish a successful landing,
Violation of the principle "Aviate, Navigate, Communicate" by both flight crew and air traffic control, which resulted in the flight crew not following standard operating procedures at the time of initiating the go around because the pilot monitoring was diverted from his duties for a prolonged period and did not monitor the flight parameters,
The fact that the crew did not recognize the autopilot had disconnected and delayed intervention by the crew, that resulted in the aircraft entering a complex spatial position (nose up upset),
Imperfection of simulator training programs for Upset Recovery Procedures as well as lack of criteria for assessing the quality of training, which resulted in the crew being unable to recover the aircraft from the upset,
The possible impact of somatogravic illusions,
The non-addressing of prior accident investigation recommendations, geared towards elimination of risks and establishing risk level management, had prevented the prevention of this accident,
Lack of proper supervision of issuance of pilot certificates in accordance with achieving specified requirements and qualifications,
Failure of safety management system (SMS) in the airline, lack of guidelines for SMS development and approval, lack of a formal approach to approve/agree on SMS and pilot training by the related authorities,
Deficiencies in aviation training centers' performance and absence of verification of training quality,
Lack of requirements for flight crew to be proficient in English Language for retraining on foreign aircraft types and lack of formal approach to verify language proficiency,
lack of formal approach to conduct periodic verification of flight crew qualification,
systematic violation of crew work and rest times,
lack of training of flight crew on go around from intermediate heights in manual control potentially leading to complex spatial position (e.g. nose high upset),
The map shifts in aircraft without GPS without training of crew to operate in such conditions,
Lack of active assistance by air traffic control when the approach procedure was deviated from over a prolonged period of time,
Breach of principle "Aviate, Navigate, Communicate".
Translation via www.avherald.com
Final Report:

Crash of a Swearingen SA227AC Metro III in Red Lake: 5 killed

Date & Time: Nov 10, 2013 at 1829 LT
Type of aircraft:
Operator:
Registration:
C-FFZN
Survivors:
Yes
Schedule:
Sioux Lookout - Red Lake
MSN:
AC-785B
YOM:
1991
Flight number:
BLS311
Country:
Crew on board:
2
Crew fatalities:
Pax on board:
5
Pax fatalities:
Other fatalities:
Total fatalities:
5
Captain / Total flying hours:
5150
Captain / Total hours on type:
3550.00
Copilot / Total flying hours:
2200
Copilot / Total hours on type:
1060
Aircraft flight hours:
35474
Circumstances:
Flight from Sioux Lookout was uneventful till the final descent to Red Lake completed by night and in light snow with a ceiling at 2,000 feet and visibility 8 SM. On final approach to runway 26, crew reported south of the airport and declared an emergency. Shortly after this mayday message, aircraft hit power cables and crashed in flames in a dense wooded area located 800 meters south of the airport. Two passengers seating in the rear were seriously injured while all five other occupants including both pilots were killed.
Probable cause:
A first-stage turbine wheel blade in the left engine failed due to a combination of metallurgical issues and stator vane burn-through. As a result of the blade failure, the left engine continued to operate but experienced a near-total loss of power at approximately 500 feet above ground level, on final approach to Runway 26 at the Red Lake Airport. The crew were unable to identify the nature of the engine malfunction, which prevented them from taking timely and appropriate action to control the aircraft. The nature of the engine malfunction resulted in the left propeller being at a very low blade angle, which, together with the landing configuration of the aircraft, resulted in the aircraft being in an increasingly high drag and asymmetric state. When the aircraft’s speed reduced below minimum control speed (VMC), the crew lost control at an altitude from which a recovery was not possible.
Final Report:

Crash of a Mitsubishi MU-2B-25 Marquise in Owasso: 1 killed

Date & Time: Nov 10, 2013 at 1546 LT
Type of aircraft:
Operator:
Registration:
N856JT
Flight Type:
Survivors:
No
Schedule:
Salina - Tulsa
MSN:
306
YOM:
1974
Location:
Crew on board:
1
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
1
Captain / Total flying hours:
2874
Captain / Total hours on type:
12.00
Aircraft flight hours:
6581
Circumstances:
Radar and air traffic control communications indicated that the Mitsubishi MU-2B-25 was operating normally and flew a nominal flightpath from takeoff through the beginning of the approach until the airplane overshot the extended centerline of the landing runway, tracking to the east and left of course by about 0.2 nautical mile then briefly tracking back toward the centerline. The airplane then entered a 360-degree turn to the left, east of the centerline and at an altitude far below what would be expected for a nominal flightpath and intentional maneuvering flight given the airplane's distance from the airport, which was about 5 miles. As the airplane was in its sustained left turn tracking away from the airport, the controller queried the pilot, who stated that he had a "control problem" and subsequently stated he had a "left engine shutdown." This was the last communication received from the pilot. Witnesses saw the airplane spiral toward the ground and disappear from view. Examination of the wreckage revealed that the landing gear was in the extended position, the flaps were extended 20 degrees, and the left engine propeller blades were in the feathered position. Examination of the left engine showed the fuel shutoff valve was in the closed position, consistent with the engine being in an inoperative condition. As examined, the airplane was not configured in accordance with the airplane flight manual engine shutdown and single-engine landing procedures, which state that the airplane should remain in a clean configuration with flaps set to 5 degrees at the beginning of the final approach descent and the landing gear retracted until landing is assured. Thermal damage to the cockpit instrumentation precluded determining the preimpact position of fuel control and engine switches. The investigation found that the airplane was properly certified, equipped, and maintained in accordance with federal regulations and that the recovered airplane components showed no evidence of any preimpact structural, engine, or system failures. The investigation also determined that the pilot was properly certificated and qualified in accordance with applicable federal regulations, including Special Federal Aviation Regulation (SFAR) No. 108, which is required for MU-2B pilots and adequate for the operation of MU-2B series airplanes. The pilot had recently completed the SFAR No. 108 training in Kansas and was returning to Tulsa. At the time of the accident, he had about 12 hours total time in the airplane make and model, and the flight was the first time he operated the airplane as a solo pilot. The investigation found no evidence indicating any preexisting medical or behavioral conditions that might have adversely affected the pilot's performance on the day of the accident. Based on aircraft performance calculations, the airplane should have been flyable in a one engine-inoperative condition; the day visual meteorological conditions at the time of the accident do not support a loss of control due to spatial disorientation. Therefore, the available evidence indicates that the pilot did not appropriately manage a one-engine-inoperative condition, leading to a loss of control from which he did not recover. The airplane was not equipped, and was not required to be equipped, with any type of crash resistant recorder. Although radar data and air traffic control voice communications were available during the investigation to determine the airplane's altitude and flight path and estimate its motions (pitch, bank, yaw attitudes), the exact movements and trim state of the airplane are unknown, and other details of the airplane's performance (such as power settings) can only be estimated. In addition, because the airplane was not equipped with any type of recording device, the pilot's control and system inputs and other actions are unknown. The lack of available data significantly increased the difficulty of determining the specific causes that led to this accident, and it was not possible to determine the reasons for the left engine shutdown or evaluate the pilot's recognition of and response to an engine problem. Recorded video images from the accident flight would possibly have shown where the pilot's attention was directed during the reported problems, his interaction with the airplane controls and systems, and the status of many cockpit switches and instruments. Recorded flight data would have provided information about the engines' operating parameters and the airplane's motions. Previous NTSB recommendations have addressed the need for recording information on airplane types such as the one involved in this accident. Recorders can help investigators identify safety issues that might otherwise be undetectable, which is critical to the prevention of future accidents.
Probable cause:
The pilot's loss of airplane control during a known one-engine-inoperative condition. The reasons for the loss of control and engine shutdown could not be determined because the airplane was not equipped with a crash-resistant recorder and postaccident examination and testing did not reveal evidence of any malfunction that would have precluded normal operation.
Final Report:

Crash of a Swearingen SA227AC Metro III in Riberalta: 8 killed

Date & Time: Nov 3, 2013 at 1556 LT
Type of aircraft:
Operator:
Registration:
CP-2754
Survivors:
Yes
Schedule:
Trinidad - Riberalta
MSN:
AC-721B
YOM:
1989
Flight number:
AEK025
Location:
Country:
Crew on board:
2
Crew fatalities:
Pax on board:
16
Pax fatalities:
Other fatalities:
Total fatalities:
8
Circumstances:
Following an uneventful flight from Trinidad, the crew started the descent to Riberalta Airport in poor weather conditions with a visibility reduced to 3 km due to rain falls. After touchdown on wet runway 14, the aircraft was unable to stop within the remaining distance. It overran, collided with obstacles and came to rest upside down, bursting into flames, some 300 metres short of runway 32 threshold. Ten people were rescued while eight passengers were killed. The aircraft was totally destroyed. The exact circumstances of the accident remains unclear.

Crash of a Beechcraft C90 King Air in Springdale: 2 killed

Date & Time: Nov 1, 2013 at 1742 LT
Type of aircraft:
Operator:
Registration:
N269JG
Flight Type:
Survivors:
No
Schedule:
Pine Bluff - Bentonville
MSN:
LJ-949
YOM:
1981
Crew on board:
1
Crew fatalities:
Pax on board:
1
Pax fatalities:
Other fatalities:
Total fatalities:
2
Captain / Total flying hours:
3367
Captain / Total hours on type:
100.00
Aircraft flight hours:
11396
Circumstances:
As the airplane was descending toward its destination airport, the pilot reported to an air traffic controller en route that he needed to change his destination to a closer airport because the airplane was low on fuel. The controller advised him to land at an airport that was 4 miles away. Shortly after, the pilot contacted the alternate airport’s air traffic control tower (ATCT) and reported that he was low on fuel. The tower controller cleared the airplane to land, and, about 30 seconds later, the pilot advised that he was not going to make it to the airport. The airplane subsequently impacted a field 3.25 miles southeast of the airport. One witness reported hearing the engine sputter, and another witness reported that the engine “did not sound right.” Forty-foot power lines crossed the field 311 feet from the point of impact. It is likely that the pilot was attempting to avoid the power lines during the forced landing and that the airplane then experienced an inadvertent stall and an uncontrolled collision with terrain. About 1 quart of fuel was observed in each fuel tank. No evidence of fuel spillage was found on the ground; no fuel stains were observed on the undersides of the wing panels, wing trailing edges, or engine nacelles; and no fuel smell was observed at the accident site. However, the fuel totalizer showed that 123 gallons of fuel was remaining. Magnification of the annunciator panel light bulbs revealed that the left and right low fuel pressure annunciator lights were illuminated at the time of impact. An examination of the airframe and engines revealed no anomalies that would have precluded normal operation. About 1 month before the accident, the pilot had instructed the fixed-base operator at Camden, Arkansas, to put 25 gallons of fuel in each wing tank; however, it is unknown how much fuel was already onboard the airplane. Although the fuel totalizer showed that the airplane had 123 gallons of fuel remaining at the time of the crash, information in the fuel totalizer is based on pilot inputs, and it is likely the pilot did not update the fuel totalizer properly before the accident flight. The pilot was likely relying on the fuel totalizer instead of the fuel gauges for fuel information, and he likely reported his low fuel situation to the ATCT after the annunciator lights illuminated.
Probable cause:
A total loss of power to both engines due to fuel exhaustion. Also causal were the pilot’s reliance on the fuel totalizer rather than the fuel quantity gauges to determine the fuel on
board and his improper fuel planning.
Final Report:

Crash of a Antonov AN-2 in Tayozhny: 2 killed

Date & Time: Oct 26, 2013 at 2015 LT
Type of aircraft:
Operator:
Flight Type:
Survivors:
Yes
Schedule:
Yerbogachon - Tayozhny
Country:
Region:
Crew on board:
2
Crew fatalities:
Pax on board:
2
Pax fatalities:
Other fatalities:
Total fatalities:
2
Circumstances:
Following an illegal flight from Yerbogachon (Irkutsk region), the crew started a night approach to Tayozhny (Boguchany district of the Krasnoyarsk region) Airfield. In poor visibility due to the night, the crew was unable to establish a visual contact with the abandoned airstrip. Two approaches were abandoned. During a third attempt, the single engine airplane impacted trees and crashed in a wooded area located 35 metres short of runway, bursting into flames. Both pilots were killed and both passengers were seriously injured.
Probable cause:
According to investigations, the aircraft did not have any CofA or registration certification, and it was unknown to the Russian registry. It is believed that the flight was illegal as the crew was attempting to land on an abandoned airfield and therefore not equipped for night operations.

Mishap of a Fokker F27 Friendship 500F in Paris-Roissy-CDG

Date & Time: Oct 25, 2013 at 0125 LT
Type of aircraft:
Operator:
Registration:
I-MLVT
Flight Phase:
Flight Type:
Survivors:
Yes
Schedule:
Paris - Dole
MSN:
10373
YOM:
1968
Flight number:
MNL5921
Country:
Region:
Crew on board:
2
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
0
Circumstances:
The crew was performing a night mail flight from Paris-Roissy-CDG Airport to Dole-Jura (Tavaux) Airport on behalf of Europe Airpost. Shortly after takeoff, while climbing to an altitude of 1,000 feet, the left propeller detached and impacted the left part of the fuselage, causing a large hole. The crew declared an emergency and was cleared for an immediate return. The aircraft landed safely less than 10 minutes later and was parked on the apron. Both pilots were uninjured and the aircraft was damaged beyond repair. The propeller was found in an open field in Mesnil-Amelot, near the airport. Nobody on ground was injured.
Probable cause:
The n°2 propeller blade root on the left engine failed due to fatigue, resulting in separation from the propeller hub and then interaction with the n°1 blade and its disconnection from the propeller hub. The imbalance created by the loss of these two blades led to the front part of the engine being torn off. The cause of the fatigue cracking could not be determined with certainty. The following may have contributed to the fatigue fracture of the propeller blade root:
- Insufficient preloading of the propeller, increasing the stress exerted on it. The lack of maintenance documentation made it impossible to determine the preload values of the bearings during the last general overhaul;
- The presence of manganese sulphide in a heavily charged area of the propeller. The presence of this sulphide may have generated a significant stress concentration factor, raising the local stress level.
The tests and research carried out as part of this investigation show that the propeller blade root is made of a steel whose microstructure and composition are not optimal for fatigue resistance. However, the uniqueness of the rupture more than 50 years after commissioning makes it unlikely that the rate of inclusions, their distribution, size, or sulphur content of the propeller is a contributing factor in the accident.
Final Report:

Crash of a Pilatus PC-6/B2-H4 Turbo Porter near Namur: 11 killed

Date & Time: Oct 19, 2013 at 1535 LT
Operator:
Registration:
OO-NAC
Flight Phase:
Survivors:
No
Schedule:
Namur - Namur
MSN:
710
YOM:
1969
Location:
Country:
Region:
Crew on board:
1
Crew fatalities:
Pax on board:
10
Pax fatalities:
Other fatalities:
Total fatalities:
11
Captain / Total flying hours:
2919
Captain / Total hours on type:
332.00
Aircraft flight hours:
16159
Aircraft flight cycles:
34903
Circumstances:
On 19 October 2013, the Pilatus Porter was being used for parachute drops. The day started normally with the first take-off at 07:21. Each flight transported 9 or 10 passengers. Except for the first two, all the flights of that day were conducted by the same pilot. The aircraft’s last landing in EBNM was at 13:20 to board the next group of 10 parachutists. After the take-off, the aircraft appeared again on the radar at 13:28 at an altitude of 1200 ft. At 13:28:52, the EBCI Air Traffic Control Officer (ATCO) instructed the aircraft to remain at 2000 ft AMSL to allow for crossing traffic, a B737 landing at EBCI, and to proceed further to the east. After the crossing, the Pilatus was authorized to climb to 5000 ft. At 13:33:32, when the aeroplane was flying at 4400 ft, the pilot was authorized to turn back to the drop zone and turned towards its target, the EBNM airfield. Shortly after, a witness observed the aeroplane making a wide turn to the left. This witness monitored the aeroplane for about 40 seconds. He indicated the engine was making an abnormal noise which he compared with the explosions made by the exhaust of a rally car when decelerating. Finally, the witness heard a loud explosion ending by the dive of the aeroplane. He believed that the sound of an explosion was caused by the “engine turbine disintegration”. Another witness driving on the E42 highway saw the aeroplane performing what he perceived as being some aerobatic manoeuvers. The aeroplane was diving and was spinning. A moment later, he saw the wing break-up, including the separation and falling of smaller parts. A sailplane pilot was standing in his garden not far from the crash site. He first heard the sound of the Pilatus which he described as being typical, smooth and constant. He looked at the aeroplane and noticed it was flying at a lower altitude than usual. He stopped observing after a few seconds. 30 to 40 seconds later, he heard an abnormal noise change which he thought was a propeller pitch change or an engine power change. He looked for the aeroplane in the sky and saw the aeroplane diving with an angle of more than 45° immediately followed by a sharp pull-out angle of over 70°, followed by the upwards breaking of a wing. The aeroplane went down “as in a stall”. The witness still heard “the sound of propeller angle moving” after the wing separation. Another witness standing approximately at an horizontal distance of 600 m from the aeroplane described having heard a sound change. He looked at the aeroplane and saw the aeroplane flying horizontally, making several significant left and right roll movements of the wings before it disappearing from his view. The aeroplane crashed on a field in the territory of Gelbressée, killing all occupants. The aeroplane caught fire shortly after the impact. A big part of the left wing, elements thereof and the right sliding door of the cabin were found at 2 km from the main wreckage. Of the aircraft’s occupants, 4 parachutists were ejected from the aircraft just prior to impact.
Probable cause:
The cause of the accident is a structural failure of the left wing due to a significant negative g aerodynamic overload, leading to an uncontrollable aeroplane and subsequent crash. The most probable cause of the wing failure is the result of a manoeuvre intended by the pilot, not properly conducted and ending with an involuntary negative g manoeuvre, exceeding the operating limitations of the aeroplane.
Contributing safety factors:
• The weakness of the monitoring of the aeroplane operations by the operator.
• The lack of organizational structure between the operator and the parachute club [safety issue].
Other safety factors identified during the investigation:
• The performance of aerobatics manoeuvre with an aircraft not certified to perform such manoeuvres.
• The performance of aerobatics manoeuvre by a pilot not adequately qualified and/or trained to perform such manoeuvres.
• Transportation of unrestrained passengers, not sitting on seat during dangerous phase of the flight.
• The weakness of the legal framework and guidance for aerial work [safety issue].
• The lack of effective oversight of aerial work operations by the BCAA [safety issue].
• The lack of mandatory requirement to install devices recording flight data on board aeroplane used for parachuting [safety issue].
• Insufficient back protection for the pilot [safety issue].
• No easy determination of the weight and balance of the aeroplane due to the passengers not sitting in predetermined positions [safety issue].
• The issuing by BCAA of two distinct authorizations to the aeroplane operator and the parachute club incorporating some overlaps, which does not encourage the awareness of responsibility of the stakeholders involved [safety issue].
• Possible erroneous interpretation of the maintenance manual [safety issue].
• Violations and/or safety occurrences not reported as required by the Circular GDF-04, preventing the BCAA from taking appropriate action.
• Peer pressure of parachutists sometimes encouraging pilots to perform manoeuvres not approved for normal category aeroplanes.
• Flying at high altitude without oxygen breathing system although required by regulation.
Final Report: