What happened
On December 30, 1999, a Piper PA 28-180 Archer, registration F-GFYK, departed Nîmes Courbessac for a flight to Cuers. During the transit, the pilot elected to fly a coastal route at approximately 500 feet above sea level, passing near the Marseille Provence airport. Approximately 25 minutes into the flight, the pilot notified Marseille flight information that the engine had stopped.
Following the engine failure, the crew attempted to restart the engine, but the motor failed to restart after a period of sputtering. Due to the low altitude and the density of residential buildings along the coastline, a landing on land was not feasible. The pilot executed a turn toward the coast and performed an emergency ditching in the Boumandariel cove near Sausset-les-Pins. The three occupants on board sustained minor injuries and were rescued by a nearby pleasure boater, though they suffered from mild hypothermia. The aircraft subsequently sank.
The investigation
The investigation focused on the wreckage recovered from a depth of 17 meters. Upon examination, the power lever was found at full throttle, the mixture control was pulled, and the magneto selection was set to the left position. The electric pump was switched off.
While the engine was recovered to the surface, investigators were unable to definitively identify a mechanical defect. The investigation was significantly hindered by corrosion caused by the seawater and the fact that the engine had been dismantled for salvage operations. Consequently, the operational status of the carburetor, the mechanical fuel pump, and the magnetos could not be conclusively determined.
Regarding fuel levels, the aircraft had been refueled the previous day. Although one tank was found to be approximately 15 liters lower than the other, the aircraft had sufficient fuel for the intended flight duration.