NTSB Factual Report

On July 21, 2005, approximately 1100 mountain daylight time, a Hughes 269A helicopter, N801CP, sustained substantial damage when it collided with terrain following a loss of control during a pinnacle approach near Laurel, Montana. The commercial pilot, who was taking a check ride for his initial flight instructor rating, was not injured, and the check pilot, who was an FAA inspector, sustained minor injuries. The helicopter was registered to and operated by Northern Skies Aviation, Inc., of Laurel. Visual meteorological conditions prevailed, and no flight plan was filed for the 14 CFR Part 91 local flight that departed from the Laurel Municipal Airport about 1050.

According to the commercial pilot, during the final approach, about 300 to 400 yards from the pinnacle, he "got a bit shallow." He informed the check pilot that he "was going to level-off to regain a steep approach angle." After correcting the approach angle, he then continued the descent. Toward the end of the approach, the pilot began increasing lift to terminate the approach at a hover. He "had to do this somewhat early as we were still a bit high and a bit too far from the pinnacle." As he started to glance at the instruments, the check pilot called for a go-around. The pilot began the go-around (increasing collective and adding forward cyclic) and "then noticed our RPMs were low." The pilot stated that "the next thing I remember is our being out of control and then hitting the surface with the right side of the cabin striking the ground."

According to the check pilot, "the approach to the pinnacle was a little shallow, but for the wind conditions was acceptable. At approximately 50 feet above the pinnacle, and with about 40 knots airspeed, the approach began to get steeper. I called for a go around. [The pilot] responded by lowering collective and moving aft on the cyclic." The check pilot "noticed the airspeed slow to around 20 knots" and "observed a reduction in rotor RPM and a large increase of manifold pressure." The helicopter began to yaw to the right "rotating approximately 280 to 300 degrees clockwise prior to impact." Following the loss of control, he took the flight controls and attempted to level the helicopter and cushion the impact.

According to the operator, there was damage to the main and tail rotors, drive shafts, gearboxes, tail boom, horizontal stabilizer, cabin section, and cabin glass.

NTSB Probable Cause

the pilot's failure to maintain rotor rpm while executing a pinnacle approach, which resulted in a loss of control and collision with terrain.