Airbus AS350 N253HP accident near Draper, Utah

Probable cause

The ground recovery team member's failure to secure a rescue rope during the helicopter loading process in steep terrain, resulting in the rope fouling the helicopter's main rotor system.

NTSB analysis

The pilot reported that he and a tactical flight officer were conducting a high altitude rescue mission in "remote and nearly vertical" terrain with a public use helicopter, by doing a one-skid recovery. The purpose of this mission was to recover a fallen hiker.

A member of the three person ground recovery team had secured himself to a rescue rope that was anchored to the steep terrain above the plane-of-rotation of the main rotor system blades. Once the helicopter's right skid landed on a rock outcrop, the ground recovery team approached the helicopter to begin the loading process. During the approach to the helicopter, the rescue rope came in contact with a main rotor blade.

The pilot reported that the helicopter then, "rotated abruptly to the left and began to shake violently." The helicopter impacted terrain, the pilot regained control, and he then made an emergency landing at a lower altitude. He reported that upon applying power to land, the helicopter "began to shake violently again until touching down and reducing collective pitch." A postflight inspection revealed substantial damage to the main rotor system, the tail boom, and the empennage.

The pilot reported there were no pre-impact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for GAA15CA258 for the full record.