CircumFlightN58424 Hughes 369D accident
NTSB CEN17LA314 · 2017-08-10 · Villa Grove, CO
Docket — crew, injuries and powerplant
Summary
The commercial pilot was conducting external load operations in the helicopter to assist power line construction. While maneuvering the helicopter away from a tower at low altitude, the pilot flew the helicopter to the right while planning on backing up at the same time. The helicopter's speed to the right was faster than he had planned. Subsequently, the helicopter's main rotor hit a tower before it came into the pilot's view, and the helicopter then impacted terrain. The pilot reported that the helicopter did not have any mechanical malfunctions or failures that would have precluded normal operation. Given the pilot's statement, it is likely that he was not adequately monitoring the environment during low-level maneuvering among power line towers and failed to see a tower before the main rotors hit it.
Full narrative
"***This report was modified on June 3, 2019. Please see the docket for this accident to view the original report.***
On August 10, 2017, about 1400 mountain daylight time, a Hughes 369D helicopter, N58424, had its tail rotor impact a powerline near Villa Grove, Colorado. The pilot received serious injuries. The helicopter sustained substantial tailboom and fuselage damage. The helicopter was registered to Quicksilver Air Inc. and operated by Patrol Helicopters Inc. as a 14 Code of Federal Regulations Part 133 rotorcraft external load flight. Day visual meteorological conditions prevailed in the area about the time of the accident, and the flight was not operated on a flight plan. The local flight originated from a field near the accident site.
According to the pilot's accident report, the purpose of the flight was to assist power line construction. After pulling a sock line through several structures, the helicopter was flown inside an angle tower. As the pilot was flying the helicopter away from the angle tower, he flew the helicopter to his right while planning on backing up at the same time. The helicopter's speed to the right was faster than planned. He stated that the helicopter's main rotors contacted a tower before it came into view, and the helicopter subsequently "crashed." The pilot indicated that the helicopter did not have any mechanical malfunctions. The pilot was not wearing a helmet.
Probable cause
The pilot’s failure to maintain main rotor clearance from a power line tower during low-level maneuvering. The National Transportation Safety Board determined the probable cause of this accident.
Circumstances
- Event type
- Accident
- Highest injury
- Serious
- Weather conditions
- Visual Meteorological Cond
- Light condition
- Day
- Sky condition
- NONE
- Ceiling (ft)
- 0
- Visibility (sm)
- 10
- Wind direction
- 0
- Temperature (F)
- 79
- Distance from field
- 0.0
Aircraft
| Registration | Make | Model | Damage | FAR part |
|---|---|---|---|---|
| N58424 | HUGHES | 369D | SUBS | 133 |
Sequence of events
| # | Occurrence | Phase |
|---|---|---|
| 2 | Maneuvering-low-alt flying Low altitude operation/event defining | Climb |