Casualties unknown

2001-12-01: Bell 206B (N911KH) — Alladin Air Service — Bryce, UT

Bryce, UT, US

On December 1, 2001, a Bell 206B (registration N911KH) operated by Alladin Air Service was involved in an aviation accident near Bryce, UT. Investigators recorded the probable cause as: loss of engine power for reasons undetermined. Contributing factors were the low airspeed and altitude at which to perform an autorotation. 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 helicopter experienced an engine flameout shortly after departure, leading to a hard landing during autorotation. The rotor head separated due to mast bumping, and the fuel tank was punctured. No fuel remained in the postaccident examination. The pilot suspected sabotage.

Preflight and Departure

The helicopter was fueled to capacity the evening before departure. The engine compartment was preheated prior to start. A preflight inspection revealed no frost on the airframe or rotor blades. The particle separator was found to be clean and dry. Engine start and takeoff were normal.

Engine Failure and Autorotation

After crossing a highway approximately one-half mile south of the heliport, while at an airspeed in excess of 50 miles per hour and an altitude of about 50 to 70 feet, the engine flamed out. The pilot noticed a yaw and heard the sound of the engine shutting off. He initiated an autorotation toward a highway right-of-way.

Impact and Damage

The helicopter struck the ground hard and slid 20 to 30 feet. Mast bumping caused the rotor head to break off. The detached rotor head struck the rear of the helicopter, severing the tail section. The helicopter then spun around and rolled over onto its right side.

Postaccident Examination

Postaccident examination disclosed no fuel remaining, as the rear skid leg had punctured the fuel tank during the impact. All fuel lines and the fuel filter were intact, free of debris, and contained fuel. The turbine and compressor turned freely by hand. The pilot noted dirt on the inside of the fuel cap, initially described as consistent with dirt at the crash site. He later clarified that the dirt inside the cap was orange, similar to dirt at the heliport, while the crash site dirt was brown native soil.

Pilot's Suspicions

The pilot observed vehicle tracks in the snow behind the helipad, with footprints leading from the tire tracks to a small dirt pile and back to the helipad. Suspecting the helicopter may have been sabotaged, he contacted the Federal Bureau of Investigation (FBI) field office in St. George, Utah. He reported that over the six years the company had operated in the Bryce Canyon area, he had experienced slander, vandalism, and death threats. According to the FBI special agent, the agency would not become involved without conclusive evidence that a crime had been committed.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20011204X02354. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.