Casualties unknown

Baggage Doors Separated in Heater-Related Explosion During Taxi (N36990)

Dickinson, ND, US

On August 30, 1993, a Cessna 414A (registration N36990) operated by Fisher Sand And Gravel Co. was involved in an aviation accident near Dickinson, ND. Investigators recorded the probable cause as: the total failure of the airplane's heater system combustion air pressure safety switch. 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 taxi, a corporate twin-engine airplane experienced an explosion after the pilot activated the heater. Two baggage doors separated; a third hung by a hinge. Investigation found a faulty combustion air pressure switch.

Incident

A corporate twin-engine airplane was taxiing for departure when the pilot turned on the cockpit/cabin heater. Approximately five minutes later, an explosion occurred. The explosion caused two of the three baggage doors to completely separate from the airframe. The third door remained attached by a single hinge.

Investigation

On-scene examination revealed no explosion or flame damage to the baggage compartment interior or the interior sides of the doors. Inspection of the heater unit determined that the combustion air pressure switch failed to interrupt electrical power to the fuel solenoid valve when air pressure was removed from it. As a result, the solenoid allowed fuel to enter the heater until conditions led to the explosion. The absence of burn marks inside the baggage compartment indicates that the explosion was confined to the heater unit or its immediate vicinity, yet its force was sufficient to blow open the baggage doors.

Probable Cause

Not stated in the source.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X13086. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.