Casualties unknown

Piper PA-18 Stalls During Turn in Low Visibility After Glacier Departure (N159T)

Sheep Mountain, AK, US

On July 12, 1987, a Piper PA-18 (registration N159T) was involved in an aviation accident near Sheep Mountain, AK. Investigators recorded the probable cause as: The pilot inadvertently stalled the aircraft while turning from downwind to base leg. 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 pilot and two passengers took off from a glacier in a Piper PA-18 after repair work. Approaching a mountain pass airstrip in deteriorating weather, the pilot stalled while turning from downwind to base leg.

Flight Details

The flight originated from a glacier where the pilot and his two passengers had been performing repair work on a previously crashed aircraft. The aircraft involved was a two-place Piper PA-18. The destination was an airstrip located in a nearby mountain pass.

Weather Conditions

As the aircraft approached the destination, weather conditions were deteriorating. The ceiling was estimated at 200 feet above ground level (AGL), and visibility ranged between one-half and three miles.

Accident Sequence

Upon nearing the airstrip, the pilot reported feeling intimidated by the low clouds and rising terrain surrounding the area. While executing a turn from the downwind leg to the base leg of the traffic pattern, the pilot inadvertently stalled the aircraft. No further details about the outcome or damage were provided in the source.

Probable cause

The pilot inadvertently stalled the aircraft while turning from downwind to base leg.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X31349. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.