On September 11, 1984, a Beech 95-B55 (registration N20148) was involved in an aviation accident near Altus, OK. Investigators recorded the probable cause as: The pilot's encounter with a windshear during the flare, which resulted in an excessive rate of descent on touchdown, leading to the collapse of the left main landing gear and the left wing scraping the runway. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
An aircraft encountered a windshear during the flare at Altus Air Force Base, leading to an excessive descent rate, runway contact, collapsed left main gear, and wing scrape.
What happened
The pilot reported that while extending full flaps, the aircraft encountered a windshear during the flare phase of landing. This sudden change in wind conditions caused an excessive rate of descent upon touchdown. The impact with the runway resulted in the collapse of the left main landing gear. Subsequently, the left wing scraped along the runway surface.
The investigation
Prior to the landing attempt, personnel at Altus Air Force Base advised the pilot of the current weather conditions. Specifically, they reported winds coming from the southwest at 19 knots, with gusts reaching up to 29 knots. These wind conditions were significant factors in the encounter with the windshear during the final approach.
Findings
The primary factor contributing to the incident was the encounter with a windshear during the critical flare phase of landing. The combination of the windshear and the reported gusty southwest winds led to an excessive rate of descent. This hard landing directly caused the structural failure of the left main landing gear and the subsequent damage to the left wing.
Probable cause
The pilot's encounter with a windshear during the flare, which resulted in an excessive rate of descent on touchdown, leading to the collapse of the left main landing gear and the left wing scraping the runway.