NTSB Factual Report

On May 6, 2010, about 1030 central standard time, kit built RV-8 airplane, N127TT, impacted terrain during a forced landing following a the loss of a propeller blade while in cruise flight near Prague, Oklahoma. The private pilot, sole occupant, received minor injuries. The airplane sustained substantial damage during the accident. The aircraft was registered to and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed for the flight, which operated without a flight plan. The flight originated from the Prague Municipal Airport (O47), Prague, Oklahoma, at about 1000.

The pilot reported that he was in cruise flight for about 30 minutes when a blade from the 3-bladed propeller separated from the airplane. Due to the vibration, he shut the engine down and pulled the nose of the airplane up to stop the prop from turning. Unable to return to the airport, he elected to conduct a forced landing in a field. During the landing, the airplane missed a fence, bounced, and then flipped over, coming to rest in the inverted position. The airplane's fuselage, left wing, and vertical stabilizer were all structurally damaged in the accident. The pilot (and aircraft builder) added that he had recently installed the propeller and the accident flight was about the fifth flight, with approximately 8 flight hours on the new propeller. The propeller was identified as a ground-adjustable, 3-bladed propeller manufactured by Props, Inc.

The propeller blade lost in-flight was not located; however, the remaining part of the propeller and hub was sent to the US Forest Products Laboratory, for further examination. Without the missing propeller blade, the laboratory could not determine the reason for the separation.

NTSB Probable Cause

The in-flight separation of a propeller blade for undetermined reasons.