3 fatalities

1999-12-12: IAI 1124 Westwind (N50PL) — Panda Leasing Company — Gouldsboro, United States of America

Gouldsboro, United States of AmericaFlight

On December 12, 1999, an IAI 1124 Westwind (registration N50PL) operated by Panda Leasing Company was involved in an aviation accident near Gouldsboro, United States of America in flight. 3 people were killed. Investigators recorded the probable cause as: The improper assembly of the horizontal stabilizer trim actuator unit by maintenance personnel. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A).

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 1781203887Data APIEditorial standards

A Westwind jet crashed while descending, striking treetops and impacting a wooded area. The accident occurred after maintenance that included reassembly of the horizontal stabilizer trim actuator. Investigation found the actuator was improperly assembled, leading to disconnection of the stabilizer.

Accident Narrative

Following a five-hour flight, a Westwind jet began its descent to the airport. Air traffic control instructed the flight crew to cross a VOR at 18,000 feet and then to cross an intersection at 6,000 feet. The crew needed to descend 12,000 feet over 36 nautical miles to meet the crossing restriction. They acknowledged the clearance, and no further transmissions were received from the airplane. The airplane subsequently struck treetops and impacted the ground in a wooded area.

Maintenance Background

The accident flight was the airplane's first flight after maintenance. Maintenance work included disassembly and reassembly of the horizontal stabilizer trim actuator. Examination of the actuator at the accident site revealed that components of the actuator were separated and displayed no damage where they would have been attached.

Examination Findings

Further examination by the Safety Board revealed that the actuator had not been properly assembled in the airplane. A similar actuator was improperly assembled and installed in a static airplane for a ground test. When the actuator was run, the jackscrews were observed backing out of the rod end caps within the first few actuations of the pitch trim toward the nose-down position. As the pitch trim continued toward the nose-down position, the jackscrews became disconnected from the rod end caps, and the horizontal stabilizer became disconnected from the actuator.

The passenger was Peter Lahaye, founder and owner of the Lahaye Laboratories and the aircraft.

Probable cause

The improper assembly of the horizontal stabilizer trim actuator unit by maintenance personnel.