Casualties unknown

Nose Gear Collapse on Landing Due to Faulty Micro Switch Wiring (N67876)

Miami, FL, US

On October 25, 1985, a Cessna 402C (registration N67876) operated by Gull Air,inc. was involved in an aviation accident near Miami, FL. Investigators recorded the probable cause as: The broken lead wire on the #5 pole of the nose landing gear position micro switch caused a false down-and-locked indication, leading to the nose gear not being locked in the down position and subsequent collapse on 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 rollout on Runway 12, the nose gear assembly folded after touchdown. Investigation revealed a broken lead wire on the #5 pole of the nose landing gear position micro switch caused a false down-and-locked indication.

Incident Overview

The pilot reported conducting a normal approach to Runway 12. During the landing rollout, as the nose of the aircraft touched down, the nose gear assembly folded, causing the aircraft to slide to a stop.

Post-Crash Examination

A post-crash examination of the aircraft disclosed that the green light for the nose gear remained illuminated regardless of the landing gear position. This anomaly was traced to a broken lead wire on the #5 pole of the nose landing gear position micro switch. This micro switch serves a dual function: it activates the green indicator light and also controls the hydraulic pressure that holds the gear in the locked position.

Findings

Due to the broken lead wire, the micro switch failed to properly sense the gear position. Consequently, the pilot received a down-and-locked indication even though the nose gear was not actually locked in the down position. The absence of hydraulic pressure to secure the gear allowed it to fold upon touchdown.

Probable cause

The broken lead wire on the #5 pole of the nose landing gear position micro switch caused a false down-and-locked indication, leading to the nose gear not being locked in the down position and subsequent collapse on landing.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001214X38078. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.