On October 6, 2004, a Hughes 369HS (registration N74AM) was involved in an aviation accident near Pacific Ocean, PO. Investigators recorded the probable cause as: The pilot's failure to release the left tie-down strap before attempting takeoff, which led to an uncontrolled roll and subsequent structural damage from rotor contact. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter sustained severe damage when its tail boom was severed by main rotor blades during a takeoff attempt from a fishing vessel, caused by the pilot failing to release a tie-down strap.
What happened
The incident occurred while a helicopter was attempting to depart from a fishing vessel located on the high seas. The pilot initiated the takeoff sequence but failed to ensure that all ground restraints were removed prior to applying power. Specifically, the left tie-down strap remained attached to the helicopter's landing gear during the ascent.
As the aircraft attempted to lift off, the residual tension from the unreleased tie-down caused the helicopter to roll violently onto its side. This uncontrolled lateral movement resulted in the main rotor blades striking the tail boom. The impact was severe enough to sever the tail boom completely and destroy the main rotor blades.
Probable cause
The pilot's failure to release the left tie-down strap before attempting takeoff, which led to an uncontrolled roll and subsequent structural damage from rotor contact.