Piper PA-32-301 N8152Z accident near Kodiak, Alaska

Probable cause

A partial loss of engine power while on approach to land due to a disconnected throttle control linkage, and the maintenance director's inadequate inspection of the throttle linkage during maintenance.

NTSB analysis

The pilot and the operator's director of maintenance (DOM) were on a postmaintenance check flight. According to the pilot, while approaching to land, the throttle control became inoperative, resulting in a partial loss of engine power. The pilot selected a tidal beach as a forced landing site but was unable to reach it and landed in shallow water short of the site. The airplane sustained substantial damage to the wings and fuselage. The DOM reported that, while troubleshooting a recurring complaint of low engine manifold pressure, he noticed that the castellated nut, which connects the throttle linkage to the fuel control servo, was loose. He said that he removed the cotter pin, tightened the nut, and reinstalled the cotter pin. A postaccident engine examination revealed that a self-locking nut was missing from the throttle linkage arm, resulting in the disconnection of the throttle cable. The DOM said that the missing locknut was not the same one that he tightened but was a nut on the other end of the throttle linkage arm, about 2 inches from the castellated nut that he tightened. The DOM noted that he should have checked the security of the self-locking nut, but he did not. The self-locking nut was not recovered.

Text from the NTSB. Open the NTSB docket for ANC11CA075 for the full record.