What happened
On August 15, 2007, at approximately 18:07 UTC, a Robinson R22 Beta helicopter was performing training maneuvers at the Wr. Neustadt Ost (LOAN) airfield in Austria. The pilot, who was practicing for a helicopter instructor rating, was conducting various maneuvers including circuit patterns, hovering, and autorotations. Because solo flights in this aircraft type are only permitted from the right seat, an experienced pilot sat in the right seat as a passenger.
During the final stages of an autorotation, at an altitude of approximately 1500 ft AGL, the pilot moved the throttle to idle. As the aircraft descended to between 30 and 50 ft AGL, the pilot initiated the flare and increased the throttle to full open. During this flare maneuver, the aircraft experienced an uncontrolled yawing motion around the vertical axis. This was followed by oscillating movements across the lateral and longitudinal axes. The pilot attempted to stabilize the aircraft using the pedals and cyclic control, eventually managing to stop the rotation and land on the skids.
Upon impact with the ground, the tail boom, tail rotor gearbox, and tail rotor were damaged. There were no injuries to the pilot or the passenger, and both occupants were able to exit the aircraft independently.
The investigation
The SUB examined the aircraft, the flight conditions, and the pilot's actions. Technical inspections of the Robinson R22 Beta by both the SUB and the manufacturer, Robinson Helicopter Company, found no evidence of mechanical failure or pre-existing technical defects. The investigation also reviewed the pilot's flight experience and the execution of the autorotation procedure.
Findings
- The aircraft was airworthy at the time of the accident.
- The primary cause of the accident was the loss of tail rotor effectiveness resulting from ground contact during the flare.
- The pilot had relatively low total flight experience on helicopters.
- The autorotation was not performed according to established procedures.
- The flare was performed too late and at too steep an angle.
- Incorrect tail rotor pedal positioning, whether by the pilot or the passenger, cannot be ruled out as a contributing factor.