On September 8, 1989, a Piper PA-31-350 (registration N3554P) operated by Aviation Services West, Inc. was involved in an aviation accident near Monument Valley, UT. Investigators recorded the probable cause as: THE PILOT'S FAILURE TO ADEQUATELY COMPENSATE FOR WINDSHEAR. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
Two preceding aircraft reported windshear on final approach. The pilot experienced airspeed fluctuations, a stall horn, steep sink rate, and the right landing gear struck a sand mound before a safe landing.
Incident Overview
Two aircraft that landed ahead of the flight reported windshear on final approach. According to the pilot, while on final approach approximately one mile from the threshold, the flight encountered a 15-knot increase in airspeed, immediately followed by a 15-knot decrease. After these fluctuations, the aircraft returned to a normal approach profile and speed.
Sequence of Events
On short final, the pilot heard the stall warning horn. In response, he advanced both throttles fully forward. Subsequently, the aircraft entered a steep sink rate. The aircraft struck a sand mound with the right landing gear. The pilot was able to recover and landed the aircraft without further incident.