Pilot Debrief

FAIRCHILD HILLER FH-1100 near Cody, WY — 2012-07-31

Final reportWPR12LA341
Sign in to save
Date
2012-07-31
Location
Cody, WY, USA
Aircraft
FAIRCHILD HILLER FH-1100
Registration
N5038F
Category
Helicopter
Highest injury
None
Fatalities
0
Phase of flight
Cruise

Probable cause

The failure of a tail rotor driveshaft coupling due to fatigue.

NTSB narrative

The pilot reported that while in cruise flight, the rear of the helicopter suddenly began to vibrate. He performed an autorotation to a field, and the helicopter landed hard. The tailboom and main transmission mounts were substantially damaged. The pilot reported that a tail rotor driveshaft coupling had split in half, which resulted in a loss of tail rotor drive. Postaccident examination of the tail rotor driveshaft coupling revealed that the coupling failure was initiated by fatigue cracking. A complete history of the part was not available; therefore, the total time in service of the part could not be determined.

Analysis

Primary failure mode
Mechanical failure

NTSB coding

Evidence available

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

Docket documents5

Related mishaps