Casualties unknown

1990-08-09: Cessna 421 (N76SH) — Concord, CA

Concord, CA, US

On August 9, 1990, a Cessna 421 (registration N76SH) was involved in an aviation accident near Concord, CA. Investigators recorded the probable cause as: THE PILOT'S FAILURE TO FOLLOW THE ELECTRICAL SYSTEM FAILURE CHECKLIST. CONTRIBUTING TO THIS ACCIDENT WAS THE TOTAL ELECTRICAL FAILURE FOR UNDETERMINED REASONS AND THE LANDING GEAR BEING UNLOCKED. 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 1781061362Data APIEditorial standards

A pilot experienced an intermittent then total electrical failure after departure from Concord Airport. During the failure, the landing gear was extended electrically. Upon landing, the main landing gear collapsed. The pilot did not use the handcrank to verify gear locking.

Incident Overview

Shortly after departing from Concord Airport, the pilot encountered an intermittent electrical failure, which soon progressed to a total electrical failure.

Electrical Failure and Landing Gear Extension

During the intermittent phase of the electrical failure, the pilot electronically extended the landing gear. While the gear was being extended, the aircraft suffered a total electrical failure.

Landing and Collapse

The pilot returned to Concord Airport and executed a landing. On touchdown, the main landing gear collapsed.

Post-Accident Actions

After the aircraft came to a stop, the pilot switched off all electrical switches, including the battery and master switch. The pilot later stated that he believed the landing gear had extended and locked before the total electrical failure, and he was unable to check the landing gear warning lights to confirm that the gear was down and locked. According to the pilot, he did not follow the appropriate checklist or use the handcrank to ascertain that the landing gear was fully extended and locked.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X24053. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.