Probable cause
The pilot did not maintain rotor blade clearance from an installation rope while maneuvering to install power lines.
NTSB analysis
A lineman was on the skid of the helicopter installing high-power electrical lines on a power line structure. The pilot positioned the helicopter about 30 to 50 feet from the structure. The main rotor blades made contact with an installation rope, which then wrapped around the mast as the blades pulled it in. The pilot lost control of the helicopter, and it began an uncontrolled descent to the ground. A postaccident examination of the airframe and engine revealed no mechanical anomalies that would have precluded normal operation. It is likely that the pilot misjudged the distance between the rotor blades and the installation rope.
Text from the NTSB. Open the NTSB docket for WPR11LA122 for the full record.
Event
- Date
- Feb 4, 2011
- Type
- Accident
- Place
- Elverta, California
- Highest injury
- Minor
- Minor injuries
- 2
- Weather
- Visual (VMC)
- Light
- Dawn
Mcdonnell Douglas Helicopters 369E (MD500E)
- N-number
- N416WC
- Category
- Helicopter
- Damage
- Substantial
- Operating rule
- Part 133 (external load)
- Purpose of flight
- Other work use
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.