What happened
On 19 July 2021, a Cessna 182, registration F-HAEB, was conducting a cross-country flight from Avignon-Caumont airport to Propriano. The aircraft was carrying a pilot and two passengers under VFR conditions. While cruising at 9,500 feet, the pilot observed low manifold pressure. Upon attempting to adjust the pressure, a loud suction noise occurred, followed by a sudden and significant reduction in engine power. An engine failure warning light illuminated on the instrument panel.
The pilot attempted the prescribed emergency procedures for an engine failure in flight, eventually switching the engine to "Mechanical Backup" mode. During the subsequent descent, the pilot notified the Ajaccio flight information service of the engine problem. Following instructions from the controller, the pilot aimed for a coastal area near passing vessels. An EC120 helicopter pilot nearby observed a trail behind the aircraft and diverted to assist by directing the crew toward nearby sailing boats.
As the aircraft approached the water, the pilot configured the plane with full flaps. During the ditching in the Gulf of Porto, the aircraft struck the water, overturned, and sank rapidly. The crew and passengers successfully evacuated the aircraft and deployed a life raft. The occupants were rescued by the crew of a nearby catamaran within minutes of the impact.
The investigation
The investigation focused on the sequence of events leading to the power loss and the subsequent ditching. Because the aircraft sank in deep water, the wreckage could not be recovered for examination. The BEA examined engine parameters, flight manual procedures for the SAFRAN SMA SR305-230-E-MA02 turbocharged diesel engine, and the pilot's communications with air traffic control.
Findings
- The pilot reported that the manifold temperature reached 890°C, significantly exceeding the maximum limit of 790°C specified in the flight manual.
- The engine failure was characterized by a sudden loss of power following a suction noise, though the propeller continued to rotate.
- The activation of the emergency locator transmitter (ELT) at a high altitude (approximately 6,500 feet) created significant radio interference. This noise made it difficult for the pilot to understand instructions from the controller and hindered the execution of emergency procedures.
- The successful evacuation was attributed to the pilot's familiarity with ditching procedures and the timely assistance of the helicopter pilot and nearby maritime vessels.