Pilot Debrief

HILLER-TRI-PLEX IND.INC. UH-12B near Okeechobee, FL — 2013-01-26

Final reportERA13LA118
Sign in to save
Date
2013-01-26
Location
Okeechobee, FL, USA
Aircraft
HILLER-TRI-PLEX IND.INC. UH-12B
Registration
N9041U
Category
Helicopter
Highest injury
Minor
Fatalities
0
Phase of flight
Maneuvering

Probable cause

The pilot's failure to monitor carburetor temperature and use carburetor heat in conditions conducive to serious carburetor icing, which resulted in partial loss of engine power.

NTSB narrative

While airborne hunting, the pilot was maneuvering the helicopter at low altitude when the engine experienced a partial loss of power. During the subsequent forced landing, the helicopter struck trees and was substantially damaged. Postaccident examinations of the engine and airframe revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The atmospheric conditions at the time of the accident were conducive to serious carburetor icing at cruise power. During a postaccident interview, the pilot reported that he did not monitor the carburetor temperature or use the engine carburetor heat during the flight or subsequent to the engine power degradation. Therefore, it is likely that the carburetor accumulated ice, which subsequently resulted in a partial loss of engine power.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Pilot did not activate carburetor heat control to prevent icing.

NTSB coding

Evidence available

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

Docket documents8

Related mishaps