Maule M-5-235C N6224M accident near Three Forks, Montana

Probable cause

A loss of engine power due to degraded and incorrectly maintained ignition system components. Contributing to the accident was the pilot’s delay in turning the airplane towards the runway when the engine began to lose power.

NTSB analysis

During the first flight after the installation of avionics, and an overhauled engine, the engine started to lose power in the traffic pattern. The pilot continued to fly straight in the downwind leg of the traffic pattern and attempted to troubleshoot the problem. Despite his actions, he was unable to regain engine power and subsequently pitched for best glide and made a 180° right turn to land on the runway. By this time, the airplane had traveled too far on the downwind leg, and the airplane landed short of the runway.

Postaccident examination of the engine’s single-drive dual magneto revealed that the right magneto capacitor wire was attached utilizing an automotive terminal, however, the wire had separated from the crimped portion of the terminal. Additionally, the left magneto P-lead had areas of exposed wire, which grounded the left magneto and prevented its operation. The compounded anomalies, on both the left and right magnetos, would have resulted in a total loss of engine power.

Text from the NTSB. Open the NTSB docket for WPR22LA262 for the full record.