NTSB Factual Report

HISTORY OF FLIGHT

On July 9, 1994, at 1948 mountain daylight time, N95LG, an Aerospatiale AS350 B2 Ecureuil, was destroyed during hover 10 miles southwest of Granite, Colorado. The commercial pilot and a flight nurse were fatally injured, and three ground personnel received minor injuries. Visual meteorological conditions prevailed for the CFR part 135 flight.

The following is based on the pilot/operator report and interviews with ground rescuers. The helicopter, operating as an air ambulance, was dispatched from Provenant Medical Center in Frisco, Colorado, to 14,003-foot Mount Huron, near Granite, to pick up an injured hiker.

Ground rescue personnel said the pilot was in radio contact with them as he made his approach at the 12,200 foot level. The pilot advised them he would place the helicopter's right skid on the mountain slope to allow them to load the patient on the downhill side. Rescuers said they were beneath the rotor disc and were shielding their faces from flying debris when they heard "chopping" noises. They saw the main rotor blades strike the rocks and saw the helicopter flip over their heads and tumble down the mountain, coming to rest 800 feet away at the 11,400 foot level.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy (report P-94-84) was performed on the pilot by Pathologists Professional Corporation, Pueblo, Colorado. FAA's Civil Aeromedical Institute also performed a toxicological screen, the results of which are attached to this report.

TESTS AND RESEARCH

Examination of the accident site revealed the slope to be approximately 35 degrees. Using the flight manual's three dimensional scale drawing, three lines were drawn from the center of the helicopter, the center of the pilot's seat, and the edge of the right skid, and extended to the tip of the rotor blade. Angles formed by the intersection of these lines with the horizontal plane measured approximately 28 degrees, 28.5 degrees, and 29 degrees, respectively.

ADDITIONAL INFORMATION

The wreckage was released to the operator on July 10, 1994.

NTSB Probable Cause

FAILURE OF THE PILOT TO ASSURE MAIN ROTOR CLEARANCE FROM SLOPING TERRAIN WHILE IN A HOVER. THE TERRAIN CONDITION WAS A RELATED FACTOR.