Floatplane Forced Landing After Engine Failure Due to Fatigue Fracture (N5312T)

Incident Overview

A commercial sight-seeing flight was operating over a river valley when the engine began to run rough and subsequently lost all power. The pilot, flying a float-equipped airplane, attempted to reach a river slough for an emergency landing but could not glide far enough. The aircraft was forced to land in brush and on a sand bar, coming to rest inverted near the edge of the river.

Investigation Findings

Postaccident investigation revealed that the engine lost power due to a fatigue-induced fracture of the number five cylinder connecting rod wrist pin. The engine had been overhauled approximately two months and 180 service hours prior to the accident.

Conclusion

The forced landing was necessitated by the sudden engine failure. The pilot's attempt to reach a suitable landing area was unsuccessful due to insufficient glide distance.