Casualties unknown

2007-11-09: Bell 407 (N555BH) — Morristown, TN

Morristown, TN, US

On November 9, 2007, a Bell 407 (registration N555BH) was involved in an aviation accident near Morristown, TN. Investigators recorded the probable cause as: The pilot's failure to maintain adequate clearance from the idling main rotor blade. Contributing to the accident was the pilot's failure to comply with the manufacturer's procedure for securing the helicopter. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 8 related events involving the same aircraft type or operator are linked below.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

A pilot, after taxiing to the wrong fuel pump and assisting passengers, was struck by the helicopter's idling main rotor upon return. The cyclic friction lock was not tightened, and the flight manual did not include a procedure for exiting with rotors turning.

Incident Details

Upon arrival at the destination airport, the pilot taxied the helicopter to the fuel pumps. After stopping, the pilot realized that the pumps dispensed aviation gasoline rather than jet fuel. The pilot informed the passengers that he would assist them in unloading their baggage and then reposition the helicopter to a different fuel pump. The pilot proceeded to carry the passengers' bags and used the restroom at the fixed base operator. Later, the pilot returned to the unoccupied helicopter. While walking toward the helicopter, the pilot was struck by the idling main rotor.

Flight Manual Considerations

The helicopter's rotorcraft flight manual did not describe a procedure for the pilot to exit the helicopter while the engine and rotor continued to operate. However, the manual stated that during shutdown, the pilot should "Remain on the flight controls until the rotor has come to a complete stop." This guidance was not followed in this instance, as the pilot exited the helicopter while the rotors were still turning.

Post-Accident Examination

A post-accident examination of the helicopter revealed that the cyclic friction lock was not tightened. This condition contradicted the instructions in the flight manual's shutdown checklist. Additionally, post-mortem toxicological testing of the pilot detected a substance that, according to the testing, would not normally be expected to cause impairment of psychomotor or cognitive functions.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20071227X01994. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.