What happened
On November 18, 2015, an Extra 200, registration HB-MSW, was conducting a training flight at Bex Aerodrome (LSGB) under visual flight rules. The flight, intended as a check flight for a pilot who had not flown the type since late 2014, involved a series of touch-and-go maneuvers and a simulated engine failure exercise.
During the third circuit, the instructor instructed the pilot to perform a simulated engine failure. The pilot executed a high-gliding approach, utilizing a left slip to manage the descent. The aircraft landed on the first third of runway 33. To provide further training, the instructor ordered a subsequent touch-and-go maneuver. As the pilot applied power, the engine experienced a loss of power at an altitude of approximately 2 to 3 meters.
The instructor took control and attempted to land the aircraft within the remaining runway distance. However, the aircraft overran the runway, struck a perimeter barrier, and the propeller became entangled with wire from the fence. The aircraft then struck small trees, causing the landing gear to catch, which forced the aircraft to nose over and come to rest on its back.
The investigation
The Swiss Transportation Safety Investigation Board (SUST) examined the flight sequence, the aircraft's fuel system, and the cockpit configurations. The investigation focused on the engine's failure to provide adequate power during the takeoff phase of the touch-and-go. Investigators also reviewed the fuel selector settings and the pilot's procedures for switching between wing tanks and the center tank during the circuit.
Findings
- The accident was caused by a collision with obstacles following a runway excursion.
- The primary cause was a loss of engine power during a touch-and-go maneuver following a simulated engine failure.
- The investigation could not rule out that the fuel selector was left in the 'WING TANKS' position, which would have interrupted the fuel supply to the engine during the exercise.
- The aircraft's occupants, the pilot and the instructor, sustained two light injuries.
- The aircraft sustained significant damage, and the perimeter barrier and nearby trees were also damaged.
Safety action
Following the investigation, SUST issued a safety notice regarding fuel management for Extra 300/200 operators. The board noted that frequent switching between fuel tanks during circuit patterns increases the risk of error. Specifically, the notice advised instructors and operators to evaluate the risks of using wing tanks during circuits versus the risk of forgetting to switch to the center tank before landing, particularly as fuel transfers can occur unnoticed during slipping approaches.