19990508019969A

On may 8, 1999, at 0830 central daylight time, a Grumman American AA-5B airplane, N4546J, was substantially damaged during a forced landing following the separation of the propeller assembly from the engine while in cruise flight near Claremore, Oklahoma. The commercial rated pilot, sole occupant and owner/operator of the airplane, was not injured. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 code of federal regulations (CFR) part 91 personal flight. The flight originated from the pilot's private grass strip near ketchum, Oklahoma, at 0615, and was destined for the oklhoma city downtown airport. During an interview conducted by the investigator-in-charge, the pilot stated that he was in level cruise flight at 2,500 feet MSL, when he noticed a vibration in the aircraft. According to the pilot, the vibration became more violent and subsequently, the propeller departed the aircraft's engine. The pilot initiated an emergency landing to a field; however, noticing that his glide ratio had improved without the propeller, he elected to land at the Claremore Municipal Airport. The pilot stated that during the approach, the airplane started to porpoise, so he elected to touch down in the grass section between runway 34 and the taxiway to absorb some of the landing energy. During the landing roll, the nose landing gear collapsed and separated from the aircraft. The airplane slid across the runeay and came to rest between two runway lights. The propeller assembly (propeller with approximately 5 inches of one blade tip missing, spacer, and forward bulkhead assembly) were located three miles west of the airport. The blade tip was found in the engine cowling and the starter flywheel was located in the grass section between the runway and taxiway. The propeller flange was found intact with the engine crankshaft. The airplane's firewall was buckled, the landing gear-to-fuselage attachment points were structurally damaged, and the wing roots showed evidence of structural damage. (-23)the flight originated from the pilot's private grass strip near ketchum, Oklahoma, at 0815, and was destined for the Oklahoma city downtown airpark. The pilot stated that he was in level cruise flight when he noticed a vibration in the aircraft. The vibration became more violent and then the propeller left the aircraft. The pilot glided to an emergency landing at the Claremore Municipal Airport. On landing rollout on the grass beside therunway the nose gear buckled and separated from the aircraft.