Accident Details
The certified flight instructor (CFI) reported that after takeoff, the helicopter was hovered before beginning a practice straight-in autorotation with a planned power recovery. The autorotation was initiated between 300 and 400 feet above ground level, with a 5 to 6 knot tailwind.
During the descent, the helicopter descended faster than anticipated. Near the end of the autorotation, the CFI stated that they "lost all our lift and started our flare to try and slow us down, but by that point we were too low and still descending [too] fast." The skids then struck a mound of dirt and rock that was approximately 6 to 8 feet above ground level. The CFI did not apply power but attempted to back off the mound and turn around. Because the engine was at idle power and rotor rpm was decreasing, the helicopter spun and came to rest on its left side.
The CFI further reported that there was no preimpact mechanical failure or malfunction.
Damage
Digital pictures provided by the Federal Aviation Administration (FAA) inspector-in-charge depict structural damage to the tailboom and to the right side of the helicopter in the area of the right aft skid.