Casualties unknown

Frost on Wings Found After Floatplane Accident During Training Flight (N144Q)

Bethel, AK, US

On September 20, 2002, a DE Havilland DHC-2 (registration N144Q) operated by Ptarmigan Air was involved in an aviation accident near Bethel, AK. Investigators recorded the probable cause as: The instructor pilot's inadequate preflight by his failure to remove all frost from the wings prior to takeoff, which resulted in an inadvertent stall and in-flight collision with terrain. 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 2026-06-10Data APIEditorial standards

A float-equipped airplane with a flight instructor and commercial pilot aboard struck terrain after takeoff; postaccident inspection revealed frost on the wings.

Circumstances

A certificated flight instructor, occupying the right seat, was providing flight instruction and familiarization training to a commercial pilot in the left seat of a float-equipped airplane. The accident flight was the first flight of the day.

Accident Sequence

According to the instructor, shortly after takeoff, as the airplane climbed to about 50 feet above the water, the airplane began to buffet, and the right wing dropped. The airplane descended and subsequently struck an area of tundra-covered marshy terrain.

Damage

The airplane sustained substantial damage to the wings, fuselage, and empennage.

Postaccident Findings

The instructor reported that a postaccident inspection of the airplane revealed an accumulation of frost on the wings.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20021010X05307. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.