ROBINSON R44 - II
Flagstaff, AZ — September 25, 2013
Event Information
| Date | September 25, 2013 |
| Event Type | ACC |
| NTSB Number | WPR13CA424 |
| Event ID | 20130925X93321 |
| Location | Flagstaff, AZ |
| Country | USA |
| Coordinates | 35.36833, -111.85583 |
| Highest Injury | MINR |
Aircraft
| Make | ROBINSON |
| Model | R44 - II |
| Category | HELI |
| FAR Part | 135 |
| Aircraft Damage | SUBS |
Conditions
| Light Condition | DAYL |
| Weather | VMC |
Injuries
| Fatal | 0 |
| Serious | 0 |
| Minor | 3 |
| None | 1 |
| Total Injured | 3 |
Event Location
Probable Cause
The pilot's failure to maintain rotor rpm while landing in a gusty wind at a high density altitude.
Full Narrative
The pilot reported that he was landing the helicopter in a bowl-shaped meadow surrounded by mountains and trees. While circling the landing zone to determine the surface winds and descending, about 20 feet above ground level, the helicopter encountered a wind gust. The low rotor horn sounded and the pilot regained rpm, but another wind gust from behind again resulted in a loss of rotor rpm. The pilot said he was too low to recover, so he performed a run-on landing. The helicopter struck an earthen berm and rolled onto its left side, which resulted in substantial damage to the fuselage and tail boom. The elevation at the accident site was 8,411 feet; the density altitude was calculated to have been 10,059 feet. The pilot reported no preimpact mechanical malfunctions or failures with the helicopter that would have precluded normal operation.
About This NTSB Record
This aviation event was investigated by the National Transportation Safety Board (NTSB). NTSB investigates all U.S. civil aviation accidents to determine probable cause and issue safety recommendations to prevent future accidents.