Aerospatiale AS350
Sula, MT — April 30, 2019
Event Information
| Date | April 30, 2019 |
| Event Type | ACC |
| NTSB Number | GAA19CA238 |
| Event ID | 20190502X63800 |
| Location | Sula, MT |
| Country | USA |
| Coordinates | 45.85944, -113.96806 |
| Highest Injury | NONE |
Aircraft
| Make | Aerospatiale |
| Model | AS350 |
| Category | HELI |
| FAR Part | 137 |
| Aircraft Damage | SUBS |
Conditions
| Light Condition | DAYL |
| Weather | VMC |
Injuries
| Fatal | 0 |
| Serious | 0 |
| Minor | 0 |
| None | 1 |
| Total Injured | 0 |
Probable Cause
The pilot's failure to maintain adequate clearance from ground equipment, which resulted in a tail rotor blade impact.
Full Narrative
The helicopter pilot reported that, after an aerial application flight, he set the bucket down in a pre-determined operations zone near a semi-truck loading hopper to be refilled. He added that another truck arrived to top off the semi-truck hopper, which emitted fertilizer dust that caused the pilot concerns for his deteriorating visibility. He advised the ground crew that he was going to move out of the operations zone temporarily.
The pilot reported that he set the bucket in the new temporary operations zone. As the skid steer approached, he eased the helicopter backward to keep the other ground equipment in his view. The pilot heard a "bang", disconnected from his long-line, and landed the helicopter without further incident.
Postaccident examination revealed that the auger from the semi-truck hopper was fully extended behind the helicopter and tail rotor blade sustained substantial damage. The pilot suspected that he backed the helicopter into the extended auger.
The pilot reported that there were no preaccident mechanical failures or malfunctions 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.