Casualties unknown

Engine Failure During Cruise Descent Preparation (N6312H)

Quinhagak, AK, US

On February 28, 1992, a Cessna 207A (registration N6312H) operated by Markair Express, Inc. was involved in an aviation accident near Quinhagak, AK. Investigators recorded the probable cause as: THE TOTAL LOSS OF ENGINE POWER FOR UNDETERMINED REASONS. A CONTRIBUTING FACTOR WAS THE LACK OF SUITABLE TERRAIN ON WHICH TO MAKE THE FORCED LANDING. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 1 related events involving the same aircraft type or operator are linked below.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-06-10Data APIEditorial standards

A pilot reported a sudden engine failure while reducing power to descend from 3,700 feet. Post-accident inspection and test stand evaluation revealed no fuel or electrical issues, with the engine operating normally after disassembly.

What happened

The pilot was conducting flight operations at a cruise altitude of 3,700 feet mean sea level. During this phase of flight, he initiated a power reduction procedure in preparation for descending to an altitude of 3,000 feet. At the moment the throttle was adjusted, the engine ceased operation suddenly and completely. The pilot reported hearing a loud bang coinciding with the loss of power.

The investigation

Following the incident, investigators examined the aircraft's fuel systems and electrical components to determine the root cause of the failure. No anomalies were detected within these systems that could account for the sudden shutdown. To further isolate the issue, the engine was removed from the aircraft and subjected to a test stand evaluation.

Findings

The test stand operation demonstrated that the engine functioned normally under controlled conditions. Subsequently, the engine was disassembled for a detailed internal inspection. No mechanical defects or damage were identified during this process. The engine was reassembled and returned to service without any further issues being noted. The investigation concluded that the failure was not attributable to fuel supply problems or electrical system malfunctions.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X14065. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.