Pilot Debrief

PZL-SWIDNIK SW-4 near Fairbanks, AK — 2012-01-15

Final reportANC12LA017
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Date
2012-01-15
Location
Fairbanks, AK, USA
Airport
FAI
Aircraft
PZL-SWIDNIK SW-4
Registration
SP-SSW
Category
Helicopter
Highest injury
None
Fatalities
0
Phase of flight
Maneuvering

Probable cause

A loss of control during a simulated hydraulic emergency, which resulted in an inadvertent dynamic rollover from the which the pilot could not recover.

NTSB narrative

During a hover test above the departure end of the runway, the flight test technician turned the hydraulics system off to simulate an in-flight hydraulic failure. During a series of prearranged hover maneuvers, the pilot began to hover the helicopter to the left, at which time, the cyclic and collective became very "stiff and ratchety," which was followed by a forward and left movement of the cyclic that the pilot was unable to physically overcome. The helicopter subsequently descended, the left skid struck the runway, and the helicopter rolled onto its left side, which resulted in substantial damage to the fuselage, tail boom, and main rotor drive system. A postaccident examination revealed no evidence of any preimpact mechanical anomalies that would have precluded normal operation.

Analysis

Primary failure mode
Loss of control
First missed decision gate
Pilot could have aborted the hover test before losing control.

NTSB coding

Evidence available

  • Photos
  • 2 docket documents
View NTSB final reportView NTSB docket

Docket documents2

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