History of the Flight
The pilot, who owned the airplane, took off at 10:50 from Belle-Ile-en-Mer airport accompanied by his wife for a VFR flight to Lille Lesquin airport. At 12:43, near the Bay of the Somme, the pilot began maneuvers and descended from flight level 075 to 1,400 ft. After crossing the Somme, he started a right turn toward Amiens. At 12:59, he made several turns in descent. Shortly afterward, a witness on the ground saw the airplane pass at low height with its emergency parachute deployed. The airplane struck the ground at 13:03.
Wreckage and Parachute
The wreckage was oriented 180° in a large, obstacle-free field suitable for a precautionary landing. The absence of scars in the vegetation indicated a high vertical component. The damage showed that the aircraft contacted the ground with reduced horizontal speed and a nose-down attitude. The emergency parachute was found deployed to the rear; the left lateral strap was partially deployed, suggesting the airplane had not yet recovered a level attitude at impact. A large quantity of oil from the engine was observed on the fuselage, indicating an in-flight oil release. The engine was removed for examination. No malfunction that would impair controllability was found.
Witness Accounts
The pilot and his wife stated that the flight was proceeding normally with good weather. Shortly before the Bay of the Somme, the pilot noticed a line of clouds and performed maneuvers to descend below the cloud layer. The pilot reported seeing a warning light for a battery problem. He initially thought he could reach his planned destination but decided to divert to Amiens, where he knew repairs were available. He was maneuvering near Abbeville airport but did not divert there, believing he could extend the flight. Both stated that engine power decreased while approaching Amiens, then the engine stopped, leading to an off-field emergency landing. The pilot was seriously injured. Neither him nor his wife remembered the sequence immediately before the accident. The pilot knew that the emergency parachute should not be used at low altitude and could not explain its activation.
Flight Data Recorder Analysis
The airplane was equipped with an Avidyne EX5000 avionics suite. The Multi-Function Display recorded flight and engine parameters. At 12:33, the battery charge went from low to low: the main bus voltage dropped suddenly from 28 V to 24 V and continued to decrease. The emergency parachute was deployed at an estimated height of less than 300 ft. It appeared that the engine was voluntarily shut down by the pilot, as per the flight manual recommendation to shut down the engine before activating the parachute.
Engine Examination
The engine was a Continental IO-550-N with two alternators. The driven gear of alternator 1 was found embedded in the engine housing wall, having pierced a machined oil duct. The housing contained practically no oil. The thrust washer, which must be installed with its copper-colored face toward the alternator, was found with the copper face on the nut side—incorrect orientation. The alternator shaft was broken into two parts due to a fatigue fracture from rotating bending. The key that positions the driven gear on the shaft was sheared, and the keyway showed substantial wear.
Maintenance History
The alternator was assembled on 17 October 2011 by Aérolithe, the Cirrus importer in France, during scheduled maintenance. A new washer was reportedly installed, but the invoice was not provided. The alternator driven gear was not replaced. Between 2011 and the accident, the engine underwent several inspections but no alternator disassembly. Continental Service Bulletin 11-2 recommends inspection of the alternator driven gear every 500 hours or two years and overhaul every 2,000 hours. Cirrus updated its maintenance manual in 2014 to recommend overhaul every 2,000 hours or 12 years and gear inspection every 500 hours or two years. The version used in a September 2015 inspection recommended inspecting the gear/shaft assembly every 500 hours or two years. The accident occurred after that inspection.