Amateur-built SEAREY N452TR accident near Cokato, Minnesota

Probable cause

Separation of the composite skin on one of the three propeller blades that resulted in an in-flight vibration, and the pilot's failure to maintain clearance with the water while maneuvering to avoid obstacles in preparation for a precautionary landing.

NTSB analysis

The pilot reported that shortly after takeoff the propeller began making excessive noise and vibration. He reduced the engine power and looked for an area to make a precautionary landing. While the pilot executed a 180-degree turn in an effort to avoid obstacles in his flight path, the airplane decreased in altitude quicker than he anticipated and subsequently impacted the water. The airplane came to rest upright in approximately 3.5 feet of water. A postaccident examination of the airplane revealed that there was a separation of the composite skin on the forward face of one of the propeller blades. The separation in the skin was located about mid-span and ran the full width (chord) of the blade. The remainder of the blade appeared to be intact. The other two propeller blades appeared to be undamaged. The propeller had accumulated approximately 33 hours time in service at the time of the accident. The pilot reported that he conducted a preflight inspection and there was no visible damage to the subject propeller blade.

Text from the NTSB. Open the NTSB docket for CEN10LA484 for the full record.