2000 DHC-3T Otter accident at Saint-Didier-la-Forêt (N9758N)

Accident Overview and Aircraft Details On 1 July 2000, a DHC-3T Otter seaplane, registration N9758N, operated by a club, was destroyed during a forced landing in a field at Saint-Didier-la-Forêt (03), France. The aircraft was a single-engine turboprop model equipped with a Pratt & Whitney PT6A-135 engine, two floats, and a retractable conventional landing gear. The flight was a passenger trip from Lyon-Bron to Saint-Brieuc Armor, carrying a pilot and three passengers. The 57-year-old pilot held a Canadian PPL and had 14,200 flight hours, including 200 on type. The right-seat passenger was a 52-year-old ATPL holder with 13,000 hours. ## In-Flight Incident and Forced Landing During cruise at flight level 45, shortly after passing north of Vichy-Charmeil, the pilot experienced a sudden turbine surge and loss of propeller thrust. The propeller had feathered, rendering it unable to provide traction. The pilot attempted to return to Vichy but, unable to reach the airfield, executed a forced landing in a field used for equestrian training. The left float struck a dirt embankment, causing the aircraft to break apart. The fuselage subsequently caught fire and burned, leaving only the tail, wingtips, and nose section intact. ## Investigation Findings and Probable Cause The BEA investigation determined that the accident was caused by a hard shock to the propeller governor's beta disc guide pad, likely inflicted by a tool during non-compliant maintenance. This impact had previously cracked the pad, which eventually fragmented during the flight. The fragmentation caused the beta disc to rupture, preventing the governor from delivering oil and forcing the propeller into the feather position. The investigation noted that corrosion on the pad indicated the crack predated the accident and was unrelated to earlier maintenance work in Lyon on the reverse command cam. The right-seat passenger had attempted to contact Vichy Information multiple times without success before assisting the pilot in selecting the landing site.