What happened
On September 4, 2005, a Hughes MD 500-359 helicopter, registration D-HMOE, operated by Hahn Helicopter, was performing a flight from Germany to Gap Tallard, France. After a long flight of approximately five hours involving two previous stops for refueling, the aircraft arrived at the Gap Tallard aerodrome.
Upon landing on runway 21, the pilot transitioned into a hover within ground effect. The pilot intended to perform a right-hand rotation to vacate the runway and proceed to the parking area. During this maneuver, the aircraft began to rotate uncontrollably. The helicopter gained altitude while spinning rapidly on its vertical axis, eventually descending and impacting the ground near the runway and taxiway. The impact resulted in one fatality and one serious injury. The aircraft was destroyed in the crash.
The investigation
The BEA investigation examined the wreckage, engine, and flight controls. Investigators found no evidence of mechanical failure in the engine, the main rotor, or the flight control systems. The tail rotor and anti-torque components were found to be functional, with damage occurring only upon the final impact. The investigation also reviewed radio communications, which showed the pilot was communicating normally without reporting any onboard issues prior to the event.
Witness testimony from a ground-based pilot and amateur video footage confirmed that the aircraft exhibited an unstable approach and entered a rapid, disorganized rotation before crashing. The pilot's testimony indicated that as the aircraft began to spin, they applied maximum collective pitch to climb away from the ground, which inadvertently increased the rotation speed.
Findings
- The primary cause of the loss of control was inappropriate pedal input during a yaw rotation while hovering.
- The pilot's attempt to stop the rightward rotation with left pedal input was likely insufficient or delayed.
- As the aircraft passed 180 degrees of rotation, a tailwind component further accelerated the rotation.
- The pilot's decision to apply maximum collective pitch to gain altitude increased the torque produced by the main rotor, thereby increasing the rate of rotation.
- The pilot's fatigue following a five-hour flight, combined with relatively low flight experience, likely contributed to the improper use of the anti-torque pedals.