Pilot Debrief

McDonnell Douglas Helicopters 369E (MD500E) near Elverta, CA — 2011-02-04

Final reportWPR11LA122
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Date
2011-02-04
Location
Elverta, CA, USA
Aircraft
McDonnell Douglas Helicopters 369E (MD500E)
Registration
N416WC
Category
Helicopter
Highest injury
Minor
Fatalities
0
Phase of flight
Maneuvering

Probable cause

The pilot did not maintain rotor blade clearance from an installation rope while maneuvering to install power lines.

NTSB narrative

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.

Analysis

Primary failure mode
Loss of control
First missed decision gate
Pilot could have repositioned helicopter to avoid sock line entanglement.

NTSB coding

Evidence available

  • 4 docket documents
View NTSB final reportView NTSB docket

Docket documents4

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