Robinson Helicopter R22 BETA N7026J accident near Albuquerque, New Mexico

Probable cause

The pilot's failure to maintain main rotor rpm during a pinnacle approach, which resulted in a loss of helicopter control and collision with terrain. Contributing to the accident was the pilot's decision to attempt the approach given the helicopter's weight and the high-density altitude.

NTSB analysis

The commercial pilot was practicing pinnacle approaches in the helicopter. The pilot reported that, during the second practice approach, the helicopter gradually slowed, and, when it was about 15 ft above the ground and between 20 and 25 knots, the low-rotor rpm horn sounded. The pilot attempted to increase the rotor rpm by lowering the collective and applying aft cyclic, but the helicopter continued to descend, and the pilot subsequently performed an autorotation. During the landing, the left skid struck a hill, and the helicopter rolled on its side. A postaccident examination of the helicopter did not reveal any preimpact anomalies.

The helicopter was operating at a density altitude of about 7,000 ft, and the pilot reported that the helicopter felt "heavy," likely because the main fuel tank was filled instead of the auxiliary fuel tank before the flight. The combined effects of the helicopter's high weight and the high-density altitude reduced the helicopter's performance and limited the power available, which made it critical for the pilot to maintain rotor rpm while executing the approach.

Text from the NTSB. Open the NTSB docket for CEN14LA520 for the full record.