Pilot Debrief

ROBINSON HELICOPTER R44 near North Myrtle Beach, SC — 2022-05-26

Final reportERA22LA256
Sign in to save
Date
2022-05-26
Location
North Myrtle Beach, SC, USA
Airport
CRE
Aircraft
ROBINSON HELICOPTER R44
Registration
N132TC
Category
Helicopter
Highest injury
None
Fatalities
0
Phase of flight
Hover

Probable cause

The fractured attachment lug on the forward clutch shaft yoke due to fatigue failure with multiple origins.

NTSB narrative

Seconds after liftoff to a hover, the helicopter began to “aggressively shudder.” Loud, rapid reports were heard, and the nose of the helicopter yawed to the left. The instructor assumed control of the helicopter, closed the throttle, and performed an autorotation from a hover, landing the helicopter upright on its skids; however, the airframe sustained substantial damage. The instructor completed an engine shutdown, egressed the helicopter, and noticed that the main rotor was still turning while the tail rotor remained stationary. A cursory examination of the helicopter revealed that the clutch shaft yoke fractured at one of its two bolt lugs where the yoke attached to the flex plate. All other damage depicted appeared to be impact damage from the rotating assemblies left unsecured by the fractured lug. Examination of the damaged yoke and flexplate in the NTSB materials laboratory revealed a fractured attachment lug on the forward clutch shaft yoke due to fatigue failure with multiple origins.

Analysis

Primary failure mode
Mechanical failure
First missed decision gate
Instructor could have aborted the takeoff after initial shudder.

NTSB coding

Evidence available

  • Video
  • Photos
  • 8 docket documents
View NTSB final reportView NTSB docket

Docket documents8

Related mishaps