Primary finding
Probable cause
The pilot's failure to maintain rotor RPM during hover taxi. A contributing factor was the high density altitude weather condition.
Investigator assessment
Analysis narrative
The flight instructor said that he was on a cross-country training flight with a student. He said he was going to demonstrate an emergency autorotation to an open plateau with an elevation of approximately 7,000 feet. The flight instructor said the autorotation went well. But when he completed a right pedal turn to taxi back and applied left pedal to stop the yaw, the low rotor RPM horn sounded. He lowered the collective and rolled on the throttle as the helicopter settled to the ground. The left skid impacted first, bending the left aft skid support tube, which transmitted to the fuselage structure bending and deforming it.
Source record
Factual narrative
The flight instructor said that he was on a cross-country training flight with a student. He said he was going to demonstrate an emergency autorotation to an open plateau with an elevation of approximately 7,000 feet. The flight instructor said the autorotation went well. But when he completed a right pedal turn to taxi back and applied left pedal to stop the yaw, the low rotor RPM horn sounded. He lowered the collective and rolled on the throttle as the helicopter settled to the ground. The left skid impacted first, bending the left aft skid support tube, which transmitted to the fuselage structure bending and deforming it.