Robinson Helicopter R22 BETA N8356R accident near Temecula, California

Probable cause

The certified flight instructor's failure to maintain adequate rotor rpm during a simulated approach to landing under variable wind, and high density altitude conditions.

NTSB analysis

The certified flight instructor (CFI) was showing the student how to make a landing approach to 2,500-foot mean sea level hilly terrain. The student had about 13 hours of total flying experience, and the CFI was handling the controls. According to the CFI, the first approach to the landing site was uneventful. During the second approach the low rotor rpm warning horn activated. The CFI reported that he tried to "milk collective and get it back," but he was not successful. The CFI opined that the wind direction may have changed, and he attempted to redirect the helicopter's course into the wind. The CFI was unable to regain rpm and stop the descent. The helicopter impacted the field and rolled over. The CFI reported that when the accident occurred, the helicopter was operating near its maximum certificated gross weight. The out of ground effect hover ceiling was about 3,000 feet, and the density altitude was about 3,200 feet.

Text from the NTSB. Open the NTSB docket for WPR09CA023 for the full record.