What happened
On August 5, 2004, a Cessna U 206 F Stationair, registered F-GPRM, was performing a flight departure from the Les Sables-d’Olonne aerodrome. During the rotation phase on runway 07, the pilot noticed that the elevator was stuck. In response, the pilot attempted to abort the takeoff. During the subsequent emergency braking, the left main tire burst midway down the runway. Fearing the aircraft would overshoot the runway end, the pilot made the decision to continue the takeoff by applying full power.
The aircraft failed to become airborne and instead exited the runway, crossing the aerodrome perimeter fence, a hedge, a ditch, a field, and a road. The aircraft eventually came to rest in an uncultivated field approximately 100 meters beyond the runway end. The aircraft was destroyed in the accident.
The investigation
Investigators examined the wreckage and identified a break in the elevator trim control cable near its attachment point to the compensator. Metallurgical analysis revealed that the failure was not caused by a sudden, intense load, but rather by a prolonged period of tension.
Physical evidence showed deep transverse scratches on the cable. These marks were determined to be the result of using an improper tool during a maintenance procedure when installing the cable end fitting. This damage went undetected until the cable failed under tension during the takeoff roll.
Findings
- The primary cause of the accident was the rupture of the elevator trim control cable.
- The cable failure caused the trim to move into a full nose-down position, making it impossible for the pilot to counteract the aerodynamic forces on the elevator.
- The damage to the cable was caused by the inappropriate use of a tool during a maintenance operation.
- The accident sequence was compounded by the pilot's decision to continue the takeoff after the initial aborted attempt was compromised by a tire burst.