Pilot Debrief

ROBINSON HELICOPTER R44 near Cedar City, UT — 2022-09-30

Final reportWPR22LA363
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Date
2022-09-30
Location
Cedar City, UT, USA
Aircraft
ROBINSON HELICOPTER R44
Registration
N297SU
Category
Helicopter
Highest injury
None
Fatalities
0
Phase of flight
Hover

Probable cause

A partial loss of engine power due to a damaged cylinder intake valve and subsequent collision with terrain during an autorotation.

NTSB narrative

The flight instructor and student had just completed a series of uneventful practice maneuvers and decided to perform off-airport landings at a location that the instructor had used before. After a series of reconnaissance orbits, low passes, and power checks over the landing area and, with the helicopter operating normally, the instructor decided to proceed with a landing. The student was maneuvering at low altitude while attempting to land when they felt a jolt, and the helicopter yawed to the left. The instructor took over the controls, and attempted to maneuver away from trees but the helicopter began to vibrate and yawed aggressively to the left with an accompanying reduction in engine speed. The helicopter began to descend with the low rotor rpm horn sounding, and the instructor performed an autorotation, during which the main rotor blade cut through the tail. Postaccident examination revealed a damaged engine intake valve that would have resulted in a partial loss of engine power. The helicopter’s response during the event was consistent with a loss of engine power, although due to the altitude and environmental conditions, the helicopter was being operated at the upper limits of its performance envelope.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Instructor could have chosen a different landing area to avoid trees.

NTSB coding

Evidence available

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

Docket documents7

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