What happened
On August 22, 2012, at approximately 19:3 and 30 local time, a private McDonnell Douglas MD-500, registration F-GHLF, was performing a general aviation flight from Avignon Caumont aerodrome to a private helipad in Lançon-de-Provence.
During the final approach for a westward landing, the pilot was flying at a slow forward speed and outside of ground effect when unusual vibrations were felt. The aircraft began to yaw to the left and entered a nose-down attitude. In an attempt to correct the leftward rotation, the pilot applied right pedal. This caused the rotation to reverse, resulting in a rapid yaw to the right while the aircraft continued its descent. Despite an increase in power, the pilot lost control of the MD-500, and the aircraft struck the ground. The aircraft was destroyed.
The investigation
The investigation focused on the mechanical state of the aircraft and the flight dynamics during the loss of control. Technical examinations of the wreckage and a review of video footage captured by a witness on the ground confirmed that the aircraft did not strike any obstacles prior to the impact.
Investigators verified that the aircraft had been fully refueled at Avignon Caumont and that the weight and balance were within the manufacturer's specified limits. No mechanical malfunctions were identified through the technical inspection or the video analysis that could have contributed to the accident. The pilot, a private helicopter pilot with approximately 700 total flight hours (including 200 on type), reported a sensation of losing control over the tail rotor following the rightward correction.
Findings
- The pilot's attempt to counter the initial leftward yaw with right pedal was likely excessive.
- The combination of this excessive pedal input and a subsequent increase in power prevented the pilot from arresting the resulting rapid rightward yaw.
- The investigation could not determine the specific cause of the initial leftward yaw rotation.