What happened
On June 8, 2013, an instructional flight involving an APM30, registration F-GRRY, ended in a fatal accident near Arnouville-lès-Mantes. The flight began at Saint-Cyr-l'École, where the instructor and student pilot had originally planned to fly an HR200. However, after discovering a nose gear anomaly during the pre-flight inspection of the HR200, the crew opted to use the available APM30 instead.
During the flight, the crew performed several stall recovery exercises. Following the first two maneuvers, the aircraft experienced significant altitude loss and heading changes. During the third stall exercise, the aircraft entered a state of uncontrolled flight, eventually impacting a field with high energy and a slight nose-down attitude.
The investigation
Investigators examined the wreckage and found that the engine was receiving fuel and the flight controls were functional at the time of impact. No mechanical failures prior to the collision were identified. Data recovered from the aircraft's APIBOX flight parameter recorder provided critical insights into the flight profile.
The flight data revealed that during the third exercise, the aircraft experienced a significant increase in load factor, exceeding 2.5 g, alongside an increase in airspeed. Analysis of the flight path indicated that the third maneuver resembled a sustained stall, where the elevator was held in the aft position with reduced engine power for approximately ten to twelve seconds. This maneuver likely induced significant pitch and roll excursions.
Findings
- The primary cause of the loss of control was the instructor's decision to prolong a stall exercise at an insufficient altitude to allow for a full recovery.
- The instructor's limited experience with the APM30 (having flown it only twice) likely led to an overestimation of the safety margin, potentially applying techniques used in more familiar aircraft like the HR200 or C172.
- The decision to proceed with the planned training syllabus despite the change in aircraft type contributed to the accident, as the student had no prior experience in the APM30.
- The presence of Class A airspace restricted the crew's ability to perform the exercise at higher, safer altitudes.