On January 13, 1988, a Bell 47G-2A1 (registration XBDGH) operated by Atunera Maya SA DE Cv. was involved in an aviation accident near San Diego, CA. Investigators recorded the probable cause as: The pilot's failure to release the right side tie-down straps before attempting to hover, which resulted in the helicopter rolling over upon lift-off. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter parked on a docked ship rolled over when the pilot failed to release tie-down straps before hovering, rupturing fuel tanks and causing a fire that destroyed the aircraft and damaged the vessel.
What happened
The helicopter was secured on a helipad located aboard a ship that was currently docked. The pilot, who also served as the mechanic, failed to release two tie-down straps positioned on the right side of the aircraft before attempting to hover. When the helicopter lifted from the pad, it rolled over due to the restraints.
The investigation
The impact sequence ruptured the aircraft's fuel tanks. The spilled fuel provided the necessary conditions for a post-crash fire. This fire substantially damaged the ship and completely destroyed the helicopter.
Findings
The primary factor was the pilot's failure to release the tie-down straps before flight.
Probable cause
The pilot's failure to release the right side tie-down straps before attempting to hover, which resulted in the helicopter rolling over upon lift-off.