What happened
On November 29, 2016, a Piper PA28, registration N691J, was conducting a flight from Cannes Mandelieu to Avignon Caumont for an instrument rating practical exam. During the ILS approach to runway 17 at Avignon, the pilot attempted to extend the landing gear but noted that the red gear-in-motion light and the green down-lock lights failed to illuminate. After deciding to abort the approach and return to Cannes Mandelieu, the pilot attempted to extend the gear using the emergency extension procedure. While the green lights for the main gear illuminated, the nose gear light remained unlit.
To verify the gear position, the pilot performed low-altitude flypasts and executed several aggressive yaw maneuvers to attempt to lock the nose gear. During these maneuvers, the green light for the left main gear flickered off and then back on. Following confirmation from air traffic control that the gear appeared extended, the pilot landed on runway 35. However, during the subsequent taxi, the left main gear retracted, causing the aircraft to sustain heavy damage.
The investigation
The investigation focused on the landing gear system functionality and recent maintenance history. The aircraft had undergone its annual or 100-hour inspection on November 24, 2016, just five days prior to the accident. Records indicated that three days after this inspection, the pilot had experienced a similar gear malfunction and used the emergency extension. Maintenance personnel had subsequently replaced worn carbon brushes in the landing gear electric motor.
Post-accident inspections revealed that the emergency extension mechanism functioned correctly, allowing all three gears to extend and lock. When testing the normal landing gear command, no anomalies were detected during the examination of the aircraft.