Casualties unknown

Washer Pull-Through on Left Main Gear Leads to Runway Excursion During Landing (N966JW)

Tatitlek, AK, US

On May 10, 1989, a Cessna C-402 (registration N966JW) operated by Wilburs Incorporated was involved in an aviation accident near Tatitlek, AK. Investigators recorded the probable cause as: A small washer placed beneath the bolt head holding the upper and lower scissors assembly together pulled through on the left main gear, allowing the lower half of the main gear to pivot freely, which led to a loss of directional control during landing. 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

During landing on a gravel runway, the pilot lost directional control after applying brakes, causing the airplane to veer left and exit the runway. Examination revealed a washer pull-through on the left main gear scissors assembly.

Landing and Loss of Control

Upon touchdown on a gravel runway, the pilot-in-command began applying brakes. Shortly after, the airplane commenced veering to the left. The pilot released the brakes and attempted to correct using asymmetric power and braking, but the airplane continued left and departed the runway approximately midway down its length.

Post-Event Examination

Subsequent examination of the left main landing gear identified a failure in the scissors assembly. A small washer, which had been placed beneath the bolt head securing the upper and lower scissors components, had pulled through the assembly. This allowed the lower half of the main gear to pivot freely, compromising directional control.

The investigation did not specify the exact sequence of events leading to the washer pull-through, but the condition rendered the landing gear unable to maintain proper alignment during braking.

No other anomalies were reported in the aircraft's systems or the pilot's actions beyond the described attempts to regain control.

Probable cause

A small washer placed beneath the bolt head holding the upper and lower scissors assembly together pulled through on the left main gear, allowing the lower half of the main gear to pivot freely, which led to a loss of directional control during landing.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001213X28213. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.