What happened
On August 29, 2007, a Fouga Magister CM-170, registration F-GSHG, was performing a training flight at De Kooy Airport. The flight, which included a captain and a passenger, involved several maneuvers, including aerobatics and stalls. During a touch-and-go procedure on runway 04, the aircraft's landing gear retracted unexpectedly immediately after the main wheels touched the runway.
As the pilot attempted to maintain the nose up and apply takeoff thrust, the aircraft failed to accelerate as expected. Instead, the fuselage belly made contact with the concrete, causing the aircraft to slide several hundred meters down the runway before coming to a halt. There were 0 fatalities and no injuries to the two occupants, though the aircraft sustained severe damage.
The investigation
The Dutch Safety Board conducted an investigation involving interviews with the crew and air traffic controllers, as well as an examination of the runway markings and the aircraft's condition. Investigators noted that while the front cockpit gear lever was in the "up" position, the rear cockpit lever was positioned between "up" and "down."
A technical inspection of the landing gear system revealed no mechanical or electrical malfunctions. The investigators confirmed that the anti-retraction mechanism, which is designed to prevent gear movement while the aircraft is on the ground, was functioning correctly. Furthermore, the safety wires on the electrical override buttons were found to be intact, ruling out accidental activation of the override system.
Findings
The investigation concluded that the gear retraction was caused by human error rather than mechanical failure. The most likely cause was a misinterpretation of a verbal command during the landing flare. The captain called out "flaps 15" to indicate the required flap setting, but the passenger, who was operating the controls under the captain's direction, mistakenly believed this was a command to move the gear lever.
Several factors contributed to this error:
- The passenger was not fully familiar with the specific cockpit layout of the Fouga Magister CM-170.
- The shape of the gear lever in the Fouga Magister is similar to the flap levers found in the passenger's primary training aircraft, such as Cessna or Beechcraft models.
- The passenger's confusion was exacerbated by the fact that the specific procedure for the landing flare had not been briefed.
- The retraction occurred at the precise moment the left main gear strut was fully extended during the flare, which provided the mechanical opportunity to move the lever to the upward position.