What happened
An Aerospatiale AS350B helicopter experienced a hard landing while conducting training maneuvers. The flight was focused on practicing hovering autorotations under the supervision of a certified flight instructor (CFI). During the final phase of this specific maneuver, the student pilot was operating the controls. The CFI reported that the student abruptly lowered the collective control lever during the last hovering autorotation attempt. This sudden input resulted in the helicopter impacting the ground with significant force.
The investigation
Following the incident, the CFI provided a detailed account of the events leading to the hard landing. The instructor indicated that he failed to adequately guard the collective control during the critical phase of the last hovering autorotation. The lack of corrective input from the instructor allowed the student's abrupt control movement to go uncorrected, directly resulting in the hard landing.
Findings
The primary factor contributing to the accident was the student pilot's abrupt lowering of the collective control. Compounding this error was the CFI's failure to monitor and guard the collective control effectively during the training exercise. The combination of these actions led to the uncontrolled descent and subsequent hard landing.
Safety message
This incident highlights the importance of active monitoring and timely intervention by flight instructors during advanced maneuvering training. Effective guarding of flight controls is essential to prevent student errors from resulting in accidents.