What happened
On April 22, 2017, at Speck-Fehraltorf Airport (LSZK), a GY 201 aircraft, registration HB-SPH, was being prepared for flight. The pilot intended to start the engine manually while the aircraft was parked on the grass near Hangar West. To ensure safety during simultaneous hangar movements of other aircraft, the pilot repositioned the aircraft to face south toward the grass runway.
Upon starting the engine, the aircraft began to move forward without a pilot on board. This movement occurred because the brakes were not sufficiently applied and no wheel chocks were in place. In an attempt to intercept the moving aircraft, the pilot ran around the vehicle and jumped into the cockpit. Once seated, the pilot applied the brakes with significant force, causing the tail of the aircraft to lift approximately 20 meters from the grass runway. This maneuver resulted in the propeller tips striking the ground.
The investigation
SUST examined the sequence of events leading to the ground incident. The investigation established that the aircraft was not secured with chocks and that the braking was inadequate to prevent initial movement during the manual start. The investigation also confirmed the physical impact of the propeller with the terrain.
Findings
- The aircraft began moving autonomously because insufficient braking and the absence of wheel chocks allowed the engine's thrust to move the plane.
- The sudden application of heavy braking by the pilot after boarding caused the aircraft to pitch forward.
- The incident resulted in light injuries to the crew and light damage to the GY 201.