Piper PA-25-235 N7313Z accident near Westerly, Rhode Island

Probable cause

A total loss of engine power for reasons that could not be determined due to the postaccident salt water-damaged state of the engine.

NTSB analysis

About 12 minutes into a local banner towing flight, while flying 650 feet above the ocean, the airplane’s engine began running roughly. The pilot responded by increasing the throttle to full, richening the mixture, and applying carburetor heat, all to no avail. Shortly thereafter, the engine lost power completely, so the pilot performed a forced landing to the ocean and was later rescued by civilian boaters. The airplane was recovered from the ocean more than 1 week after the accident. The pilot/operator was able to perform a cursory inspection of the engine at the time, but no definitive cause for the loss of power was identified. Due to the salt water-damaged state of the engine, no further detailed examination could be completed. At the time of the accident, the engine had accumulated nearly 2,300 hours since its most recent overhaul and 150 hours since its most recent annual inspection. Weather conditions at an airport 6 miles from the accident location were conducive to the formation of serious carburetor ice at glide power settings.

Text from the NTSB. Open the NTSB docket for ERA12LA474 for the full record.