Seized piston leads to total loss of engine power in plane not flown in 10 years

The pilot told investigators that after an uneventful preflight inspection and engine run-up of the Avid Aircraft, he departed Runway 1 at the airport in Knoxville, Tennessee, with the engine power set to 6,300 rpm.

At 100 feet above the runway, he adjusted the engine RPM to 6,000. After about 1 minute of flying at an altitude of 400 feet AGL, the engine decreased from 6,000 rpm to totally stopped within seconds.

The pilot elected to land on a riverbank, however the airplane hit trees and a metal fence before coming to rest in the river.

The pilot conducted a post-accident examination of the airplane’s two-stroke engine and found that the piston in the power takeoff cylinder had seized during the flight. He subsequently started the engine and it operated without any anomalies.

The airplane’s most recent maintenance records were not located. The pilot reported the engine had accumulated about 177 hours of operation before the accident.

He also told investigators the airplane had not been flown for about 10 years and was in poor condition when he purchased it.

He reported that he did not perform any internal maintenance on the engine but did extensive work on the external components.

Probable Cause: A total loss of engine power due to a seized piston in the power takeoff cylinder.

NTSB Identification: 193290

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This October 2023 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.