Casualties unknown

Nose Gear Fails to Lock Due to Incorrect Rigging and Low Cable Tensions (N890US)

Charlotte, NC, US

On May 1, 1994, a Fokker F28 MK 0100 (registration N890US) operated by Usair, Inc. was involved in an aviation accident near Charlotte, NC. Investigators recorded the probable cause as: Incorrect rigging of the nosewheel steering system and low nosewheel steering cable tensions, resulting in the nose gear impinging on the side wall of the gear well and preventing extension. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 3 related events involving the same aircraft type or operator are linked below.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-06-10Data APIEditorial standards

A flightcrew reported that during landing gear extension, the nose gear did not indicate down and locked. After multiple attempts, the aircraft was landed with the nose gear not locked. Inspection revealed the nosewheel steering system was incorrectly rigged with low cable tensions, causing the nose gear to impinge on the gear well sidewall.

Summary

During a landing, the flightcrew reported that while extending the landing gear, the nose gear did not indicate down and locked. After further attempts to lower the nose gear were unsuccessful, the aircraft was landed with the nose gear not in the down-and-locked position.

Inspection Findings

A post-incident inspection revealed that the nosewheel steering system was incorrectly rigged. The nose gear could not properly center itself, and the nosewheel steering cable tensions were below required limits. This condition resulted in a situation where the nose gear would impinge on the side wall of the gear well, preventing extension.

Background

The aircraft manufacturer reported that a combination of nose gear misrigging and reduced cable tensions was required to duplicate this scenario. Approximately two weeks prior to the incident, the nosewheel steering control valve had been replaced. This replacement would have required a check of the nose gear rigging.

Probable cause

Incorrect rigging of the nosewheel steering system and low nosewheel steering cable tensions, resulting in the nose gear impinging on the side wall of the gear well and preventing extension.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001206X01204. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.