Accident Overview
A helicopter pilot was providing a ride to a passenger at a local festival when the engine began to run rough approximately 100 feet above ground and subsequently quit. The pilot initiated an emergency descent, during which the helicopter impacted trees, resulting in damage to the uninsured aircraft.
Fuel Contamination Allegation
The operator claimed that the fuel in the helicopter, his fuel truck, and his ground supply tank had been contaminated with jet fuel prior to the accident. However, subsequent testing by the National Transportation Safety Board (NTSB) revealed that the fuel could not have been contaminated. The NTSB determined that jet fuel must have been added to the helicopter and the operator's self-tested fuel samples after the accident.
Engine Examination
The engine was examined in detail and tested by the NTSB. No evidence of damage due to jet fuel contamination was found. The engine initially ran rough due to a restricted fuel nozzle; after the nozzle was changed, the engine ran within specifications (with no turbocharger). The restriction in the original nozzle was not found.
Maintenance Discrepancies
Several maintenance discrepancies were identified, including a leaking turbocharger, improperly installed fuel nozzles, a crimped fuel vent line, and a separated magneto cap. However, no conclusive evidence associated with the accident power loss was found.