Pilot Debrief

CUB CRAFTERS INC CC11-100 near Dillingham, AK — 2013-06-19

Final reportANC13CA056
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Date
2013-06-19
Location
Dillingham, AK, USA
Airport
PADL
Aircraft
CUB CRAFTERS INC CC11-100
Registration
N620Y
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Cruise

Probable cause

A loss of engine power due to carburetor icing.

NTSB narrative

The airplane departed with 24 gallons of usable fuel, which normally allows for 4.5 hours of flight. About 2.5 hours into the flight, the engine started running rough. The pilot confirmed the mixture was rich and the carburetor heat was on. About 5 minutes later the engine quit and the pilot executed a forced landing to an area of tundra-covered terrain, substantially damaging the undercarriage, fuselage, and left wing strut. A postaccident examination by a Federal Aviation Administration inspector revealed that the carburetor had separated from the engine during the forced landing, and the gascolator drain had tundra embedded in it. The pilot stated that he had turned the fuel selector to the OFF position about 30 minutes after the landing. The carburetor icing chart indicated the possibility of serious carburetor icing at the reported atmospheric conditions. The Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25A) states that first indication of carburetor ice in an airplane with a fixed-pitch propeller is a decrease in engine rpm. Additionally, it states that when conditions are conductive to carburetor icing that carburetor heat should be applied immediately and should be left ON until the pilot is certain all the ice has been removed. If ice is present applying partial heat or leaving heat on for an insufficient time might aggravate the situation. Postaccident examination of the airframe and engine revealed no preimpact mechanical malfunctions or failure that would have precluded normal operation.

Analysis

Primary failure mode
Fuel management
First missed decision gate
Pilot should have applied carburetor heat immediately upon engine roughness.

NTSB coding

Evidence available

  • 4 docket documents
View NTSB final reportView NTSB docket

Docket documents4

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