NTSB Factual Report

The certified flight instructor (CFI) stated that she had relocated the helicopter from a dolly to the taxiway in order for the student to conduct the takeoff from the taxiway. The student pilot took control of the helicopter and lifted the collective, and the helicopter began to roll to the right. The CFI stated that she lowered the collective and applied left cyclic, but the helicopter continued to roll to the right. The helicopter came to rest on its right side and sustained substantial damage to the tail boom. The CFI reported there were no mechanical malfunctions or anomalies with the helicopter.

NTSB Probable Cause

The certified flight instructor's delayed remedial action, which resulted in a loss of control and subsequent rollover.