Pilot Debrief

MOONEY M20C near Visalia, CA — 2010-09-21

Final reportWPR10LA465
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Date
2010-09-21
Location
Visalia, CA, USA
Airport
VIS
Aircraft
MOONEY M20C
Registration
N6090Q
Category
Airplane
Highest injury
None
Fatalities
0
Phase of flight
Takeoff roll

Probable cause

A partial loss of engine power during takeoff, which resulted from the failure of the spark plug retention mechanism.

NTSB narrative

The pilot applied full engine power, took off, and climbed to about 300 feet above the runway. The engine suddenly lost partial power, and the pilot elected to return to the airport for a forced landing. The airplane’s altitude was insufficient to complete the turn, and the airplane impacted the ground adjacent to the departure runway, substantially damaging the right wing. An examination of the engine revealed that the retention mechanism for the bottom No. 3 spark plug failed and the spark plug had blown out of its cylinder. Its failure appeared related to excessive wear and the loosening over time of the Heli-Coil insert. According to the Federal Aviation Administration, evidence of the Heli-Coil’s loosening would not, necessarily, have been apparent to a mechanic during routine maintenance.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Pilot could have aborted takeoff after hearing loud pop noise.

NTSB coding

Evidence available

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

Docket documents6

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