Pilot Debrief

ZENITH CH-750 near Morristown, MN — 2016-10-20

Final reportCEN17LA021
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Date
2016-10-20
Location
Morristown, MN, USA
Aircraft
ZENITH CH-750
Registration
N8681
Category
Airplane
Highest injury
Serious
Fatalities
0
Phase of flight
Initial climb

Probable cause

A total loss of engine power due to fuel vapor lock. Contributing to the loss of engine power were the corrosion of the spark plugs and the spacing of the electrode gaps.

NTSB narrative

The private pilot reported that he had started, warmed up, and then shut down the engine about 1 hour before the accident flight. Shortly after takeoff for the personal flight, the airplane's engine lost total power. Subsequently, the pilot conducted a forced landing on a hill, which resulted in substantial damage to the nose landing gear, fuselage, and left wing. The pilot said that he had fueled the airplane that morning with 82-octane automotive fuel that he had recently purchased from a service station. However, postaccident examination revealed that the fuel was yellow in color and smelled like "aged" automobile fuel. The top spark plugs appeared aged, and the electrodes were corroded, which could have affected engine performance. The airplane was not equipped with a fuel vapor return line to prevent fuel vapor lock. Given that old automotive fuel was found in the fuel system and that a fuel vapor return line had not been installed, it is likely that the engine lost power due to vapor lock. It is also likely that the corrosion of the spark plugs and the spacing of the electrode gaps contributed to the loss of engine power.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Pilot could have checked fuel selector valve before takeoff.

NTSB coding

Evidence available

  • ADS-B / radar
  • Photos
  • 11 docket documents
View NTSB final reportView NTSB docket

Docket documents11

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