Casualties unknown

Engine Failure Due to Damper Separation Leads to Crash (N756EA)

Fairbanks, AK, US

On February 9, 1989, a Cessna U206G (registration N756EA) operated by Arctic Circle Air Service Inc was involved in an aviation accident near Fairbanks, AK. Investigators recorded the probable cause as: The separation of a rear torsion vibration damper from the crankshaft boss, which caused massive internal engine damage and loss of power. 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 an engine failure during flight, resulting in a crash into a pine tree stand. Investigation revealed a separated torsion vibration damper caused massive internal damage and loss of power.

What happened

During the course of flight, the pilot experienced a sudden engine failure. Unable to maintain altitude or control, the aircraft descended rapidly and impacted a stand of pine trees while attempting to land.

The investigation

A detailed examination of the failed engine was conducted to determine the root cause of the power loss. Investigators found that one of the rear torsion vibration dampers had separated from its crankshaft boss. This structural failure triggered massive internal damage throughout the engine assembly, leading directly to the subsequent loss of power.

Findings

The separation of the torsion vibration damper was identified as the primary mechanical failure. The resulting internal damage rendered the engine inoperative, leaving the pilot with no option but to attempt an emergency landing in the surrounding terrain.

Probable cause

The separation of a rear torsion vibration damper from the crankshaft boss, which caused massive internal engine damage and loss of power.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X27676. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.