Casualties unknown

1991-08-20: Bell 47G (N4062G) — Shafter Aviation, Inc. — Kettleman City, CA

Kettleman City, CA, US

On August 20, 1991, a Bell 47G (registration N4062G) operated by Shafter Aviation, Inc. was involved in an aviation accident near Kettleman City, CA. Investigators recorded the probable cause as: The pilot's failure to ensure adequate fuel supply for the intended flight duration, which resulted in fuel exhaustion during an aerial application mission. 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 helicopter pilot lost engine power during an aerial application mission and executed a hard landing. The cause was determined to be fuel exhaustion, as the pilot could not confirm the initial fuel quantity despite estimating sufficient reserves.

What happened

During an aerial application mission, the pilot experienced a loss of engine power after approximately one hour of flight time. Unable to maintain altitude, the pilot executed a landing that resulted in significant impact with the ground. The aircraft sustained substantial damage during this hard landing event.

Prior to the incident, the pilot had estimated that the fuel quantity on board was sufficient for 1 hour and 20 minutes of operation. However, the pilot admitted to not knowing the exact quantity of fuel loaded at the time of takeoff. No mechanical failures or malfunctions were reported with the aircraft prior to the accident.

The investigation

Investigation of the wreckage revealed no evidence of pre-impact mechanical failure. The engine continued to function normally until fuel was depleted. The pilot's inability to verify the initial fuel load meant that the actual endurance of the flight could not be accurately calculated against the known consumption rate.

Findings

The primary factor in this accident was the depletion of usable fuel. The pilot failed to ensure adequate fuel reserves were loaded at takeoff and did not monitor fuel quantity effectively during the mission. This lack of precise fuel management led directly to the engine stopping due to starvation.

fuel exhaustion was the critical issue that caused the loss of power. The aerial application phase requires careful planning, and the pilot's assumption about remaining flight time proved incorrect because the starting fuel amount was unknown.

Probable cause

The pilot's failure to ensure adequate fuel supply for the intended flight duration, which resulted in fuel exhaustion during an aerial application mission.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X17905. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.