Final Report: Mechanical Led to LongRanger Power Loss
Bell 206L-1 LongRanger, Patterson, La., March 14, 2006–The LongRanger’s loss of power during cruise, the NTSB said, was due to the improper installation of an engine fuel line fitting by maintenance personnel, which resulted in a loose fitting. The NTSB listed a tailwind and the lack of a suitable site for a forced landing as factors.
When the engine quit, the commercial pilot made a hard forced landing in tall vegetation and soft ground. The two rear-seat passengers got out of the helicopter with only minor injuries, before it was engulfed in flames. The pilot and the third passenger were killed.
The fuel line to the fuel nozzle B nut could be turned by hand and did not contain a lock wire as required. The maintenance records revealed that a 50-hour fuel nozzle inspection was performed the evening before, but maintenance personnel said that engine manufacturer’s fuel nozzle installation procedures had not been followed.
Tests to determine what effect a loosefuel nozzle B nut would have on the engine’s operation found that the engine would experience a substantial loss of power that could conclude in a flameout. Conditions would have been conducive to an in-flight fire, but investigators could not determine if the fire originated in flight or during the ground impact.