Pilot Debrief

EUROCOPTER AS 350 B2 near South Pass 93A — 2011-10-07

Final reportCEN12LA039
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Date
2011-10-07
Location
South Pass 93A, USA
Aircraft
EUROCOPTER AS 350 B2
Registration
N183EH
Category
Helicopter
Highest injury
None
Fatalities
0
Phase of flight
Ground

Probable cause

Improper centering of the cyclic during a start in gusty wind conditions.

NTSB narrative

During an engine start on a helipad, the helicopter's main rotor blade contacted the tailboom, which resulted in substantial damage to the tailboom. The reported wind about the time of the accident was about 23 knots. The pilot reported that when the wind was from the east, as it was at the time of the accident, wind contact with a generator room west of the helipad resulted in occasional updrafts on the helipad. An examination of the helicopter did not reveal any preexisting anomalies that would have precluded normal operation. In the helicopter's flight manual checklist for the "Checks Before Starting the Engine," the helicopter's cyclic is to be in the neutral position and the cyclic stick friction lock adjusted. Note 1 of the checklist states, "In strong wind, apply a little forward cyclic and accelerate the engine, up to approx. 320 rpm, as fast as in compatible with t4 limitations, then follow normal procedure." A review of accidents involving the same make and model helicopters, revealed that in all of the recorded tail boom strikes by main rotor blades during start, two conditions needed to be present: cyclic not centered and air turbulence pushing strongly on the main rotor blades.

Analysis

Primary failure mode
Human factors
First missed decision gate
Pilot could have adjusted cyclic for wind conditions before engine start.

NTSB coding

Evidence available

  • 4 docket documents
View NTSB final reportView NTSB docket

Docket documents4

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