What happened
On 21 January 2019, a Piper PA-46-310P Malibu, registration N264DB, crashed approximately 22 nautical miles north-north-west of Guernsey. The flight had originated from Nantes, France. During the flight, technical issues were noted, and the aircraft eventually entered a period of uncontrolled flight. The impact resulted in all fatalities on board.
The investigation
The AAIB investigation focused on the presence of carbon monoxide (CO) within the aircraft cabin and the mechanical integrity of the engine exhaust system. Investigators examined the wreckage and analyzed the flight path, noting that the aircraft's control became erratic during the final stages of the flight. The investigation also reviewed maintenance records and the engine's turbocharger components to identify potential leak paths for exhaust gases.
Findings
- Carbon monoxide had leaked from the engine exhaust system into the aircraft cabin.
- The inflow of carbon monoxide caused the pilot to become incapacitated, leading to the loss of control of the aircraft.
- The aircraft experienced an in-flight structural failure during a final descending turn, likely due to the extreme loads placed on the airframe during the uncontrolled descent.
- Maintenance procedures for inspecting the exhaust system were reviewed, specifically regarding the detection of cracks or leaks in the heater muff and exhaust stacks.