What happened
On 23 October 1998, a Rockwell Commander 114, registration N5834N, was conducting a private flight over the Bristol Channel. While descending from 2,000 feet to 1,500 feet, the aircraft's engine began to lose power. The pilot attempted to rectify the issue by adjusting the mixture control to the full rich position, but the power loss persisted.
In response to the deteriorating situation, the pilot turned the aircraft toward the coast and declared an emergency. Despite performing engine failure procedures, the engine continued to operate at a low power setting, leading to a rapid descent. The pilot successfully executed a forced landing in a reed bed located below the high water mark on the South Wales side of the channel. While the landing gear collapsed upon impact, the pilot sustained minor injuries and was able to exit the aircraft safely.
The investigation
Following the accident, the AAIB conducted an on-site examination of the aircraft after it was recovered from the tidal area 40 hours later. The investigation focused on the engine's performance and the environmental conditions at the time of the incident.
Technical inspections of the engine and its associated systems revealed no obvious mechanical faults. The engine was capable of turning freely, oil levels were sufficient, and cylinder compressions were within acceptable limits. Furthermore, the single-drive twin magneto and its drive system were found to be serviceable. Fuel was present in both tanks and the supply pipe to the fuel injection unit.
Meteorological data from the time of the accident indicated conditions that suggested a high probability of serious icing. However, because the aircraft was equipped with a fuel-injected engine, traditional carburettor icing was not possible. The investigators also considered the possibility of ice contaminating the air intake filter or impacting the fuel injector nozzles, though such occurrences were deemed unlikely given the aircraft had been operating at high power and was not flying in rain or cloud.
Findings
- The engine experienced a significant loss of power during a descent.
- The pilot was heavily preoccupied with managing the emergency and landing the aircraft, which may have impacted the execution of engine failure drills.
- The engine failure was not attributable to any identifiable mechanical or system malfunction found during the post-accident inspection.