Casualties unknown

1983-06-09: Learjet 35 (N1976L) — Seattle, WA

Seattle, WA, US

On June 9, 1983, a Learjet 35 (registration N1976L) was involved in an aviation accident near Seattle, WA. Investigators recorded the probable cause as: The captain and co-pilot failed to correctly identify the red door warning light, misinterpreting it as a malfunctioning fuel warning light, and the cargo handler closed the door without latching it, as latching required a key that was typically used by the… 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

During takeoff, a passenger door opened, leading to an aborted takeoff. The aircraft oscillated and the right wing tip tank ruptured after ground contact. The crew had misidentified a door warning light as a fuel warning.

Incident Overview

During the takeoff roll, the passenger door of the aircraft opened, prompting an aborted takeoff. The aircraft oscillated right, left, and right before the right wing made ground contact, rupturing the right wing tip tank. The highest altitude attained during the event was about 100 feet above ground level.

Pre-Takeoff Events

Before takeoff, a cargo handler from Purolator interrupted the captain while he was closing the door to hand him a package. The captain then went to secure the package, and the cargo handler closed the door. According to the handler's interview, he closed the door but did not latch it, as latching requires a key that was typically used by the crew.

Crew Actions and Warning Light

After the captain was seated, he and the co-pilot failed to properly identify the red door warning light. They mentally dismissed it, regarding it as a malfunctioning fuel warning light, despite the fact that the door and fuel warning lights are separated by three other lights.

The Incident

During the takeoff, at approximately 110 knots, the door opened, and the abort was initiated. During the abort, the aircraft oscillated and the right wing tip tank struck the ground and ruptured.

Aftermath

The cargo handler was interviewed and confirmed closing the door but stated he never latched it because that operation required a key and was always performed by the crew. The investigation logically concludes that the door was not properly latched before takeoff, leading to its opening.

Probable cause

The captain and co-pilot failed to correctly identify the red door warning light, misinterpreting it as a malfunctioning fuel warning light, and the cargo handler closed the door without latching it, as latching required a key that was typically used by the crew.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001214X43522. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.