Casualties unknown

1989-06-24: DE Havilland DHC-2 (N5595M) — Gay, Kirk — Iliamna, AK

Iliamna, AK, US

On June 24, 1989, a DE Havilland DHC-2 (registration N5595M) operated by Gay, Kirk was involved in an aviation accident near Iliamna, AK. Investigators recorded the probable cause as: A malfunction of the magneto caused by a thick crust coating both poles, which resulted in internal binding and subsequent engine failure. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

A light aircraft crashed into a wooded area while on final approach due to a magneto malfunction that caused the engine to quit, resulting in serious injuries to both occupants.

What happened

The flight was proceeding normally until the aircraft reached the final approach phase. At this critical juncture, the engine abruptly stopped producing power. Without propulsion, the airplane lost altitude and control authority necessary to complete the landing. The pilot attempted to manage the descent but was unable to prevent impact with the terrain. The aircraft crashed into a wooded area located near the intended landing site.

The investigation

Following the accident, investigators conducted a thorough examination of the airframe and its mechanical systems to determine the root cause of the engine failure. The focus was primarily on the propulsion system, given the sudden loss of power during flight. Technicians disassembled relevant components to inspect for signs of wear, damage, or foreign object debris.

Findings

The technical analysis revealed a specific malfunction within the engine's ignition system. A detailed inspection of the magneto showed that a thick crust had formed and coated both poles. This accumulation caused the internal mechanism to bind, preventing proper operation. The binding of the magneto directly led to the cessation of engine function, which was the primary factor in the accident sequence. Both the pilot and the passenger sustained serious injuries in the impact.

Safety message

Regular inspection and maintenance of ignition components are critical to preventing internal binding and ensuring reliable engine performance during all phases of flight.

Probable cause

A malfunction of the magneto caused by a thick crust coating both poles, which resulted in internal binding and subsequent engine failure.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X28466. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.