Amateur-built SEAREY N453TS accident near New Ipswich, New Hampshire

Probable cause

A total loss of engine power due to the exhaust muffler and tailpipe assembly separating from its attach points and impacting the propeller.

NTSB analysis

The pilot reported that shortly after reaching his initial cruise altitude, he heard a “loud bang” and the pusher-style engine lost all power. The pilot unsuccessfully attempted to restore engine power multiple times. After he determined that he would be unable to restore power to the engine, the pilot performed a forced landing in a wooded area, resulting in substantial damage to the airplane.

Postaccident examination of the airplane at the accident site revealed that the exhaust muffler and tailpipe assembly was separated from the engine and not located at the accident site.

Following recovery, a postaccident examination of the airframe and engine revealed the only anomaly to be the missing exhaust muffler and tailpipe assembly. Two of the propeller blades, which were mounted aft of the engine, displayed impact damage signatures and portions of the blades had broken free, which were also not located. Only one of the eight exhaust springs that attach the exhaust muffler and tailpipe assembly to the exhaust risers remained with the exhaust risers. The spring displayed deformation on the exhaust muffler end consistent with being pulled out of position. It is likely that the exhaust muffler and tailpipe assembly had separated from the exhaust risers during flight and impacted the propeller, which resulted in a loss of power of the engine. The reason for the exhaust muffler and tailpipe separation could not be determined.

Text from the NTSB. Open the NTSB docket for ERA24LA276 for the full record.