Pilot Debrief

HUGHES 269C near Asotin, WA — 2015-07-01

Final reportWPR15FA204
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Date
2015-07-01
Location
Asotin, WA, USA
Aircraft
HUGHES 269C
Registration
N9490F
Category
Helicopter
Highest injury
Fatal
Fatalities
2
Phase of flight
Maneuvering

Probable cause

The pilot's failure to maintain adequate clearance from power lines while maneuvering in a canyon.

NTSB narrative

**This report was modified on September 30, 2016. Please refer to the public docket for this accident to view the original report.** The private pilot and passenger were on a local area flight. While maneuvering in a canyon, the helicopter impacted power lines and descended to the canyon's wall. A fire ensued and burned the surrounding area. The power lines were located 350 ft south of the wreckage with two 35-ft support structures (wood poles) on either side of the canyon about 1,452 ft apart. The two 5/16-inch diameter power lines were oriented east-west and ran horizontally parallel to one another. Ground scar analysis and wreckage fragmentation revealed that the helicopter contacted the power lines in the area of the swashplate. According to the helicopter manufacturer, if the helicopter were in level flight at cruise speed, 0.11 seconds would transpire between the contact with the first wire (canopy) and the second wire (slat and mast). Given the damage and rub marks, it is likely that, after the second wire impact, the helicopter pitched up and yawed left. Examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The private pilot had about 55 hours total time, most of which was accumulated around the accident area.

Analysis

Primary failure mode
Loss of control
First missed decision gate
Pilot could have avoided flying near powerlines in the canyon.

NTSB coding

Evidence available

  • 7 docket documents
View NTSB final reportView NTSB docket

Docket documents7

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