SEA97LA186

The pilot reported that while in cruise flight, the engine rpm dropped and the airplane began to shake. The pilot checked the gauges, the throttle and mixture, the magnetos, fuel valve position, and found nothing wrong. The pilot stated that he notified air traffic of the loss of engine power, and diverted to a nearby airpark. The pilot entered the pattern and set-up for a short field landing, however, due to a tailwind, sloping terrain, and excess airspeed, the airplane floated a considerable distance down the runway. The pilot stated that when the airplane touched down, he realized that he did not have enough runway left to stop, and opted to turn off the runway onto a steep uphill taxiway. During the roll up this taxiway, the right wing struck trees and spun the airplane around 180 degrees. During the postcrash inspection of the engine, the exhaust valve for the number three cylinder was found broken.

On August 5, 1997, at 1400 Pacific daylight time, a Cessna 172M, N73158, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, collided with trees when the airplane veered off the runway at Whidbey Airpark, Langley, Washington. Visual meteorological conditions prevailed at the time and no flight plan was filed. The airplane was substantially damaged and the private pilot and his passenger were not injured. The flight had departed from Bellingham, Washington, about one hour prior to the accident. The flight was destined for Everett, Washington.

The pilot reported in a written statement that, while in cruise flight the engine rpm dropped and the entire airplane began to shake. The pilot stated that he checked all of the gauges, throttle and mixture control, magnetos, fuel valve position, and found nothing wrong. The pilot reported to air traffic that he had a loss of engine power and was diverting to Whidbey Air Park.

After the pilot located the Air Park, he executed an emergency descent and entered the pattern for runway 16. The pilot stated that he chose runway 16, because runway 34 has a radio mast near the approach end. The pilot reported that he set-up for a short field landing, however, due to a tailwind, sloping terrain, and excess airspeed, the airplane floated a considerable distance down the runway. The airplane touched down and the pilot realized that he did not have enough runway left to stop. The pilot stated that he elected to veer off onto a steep uphill taxiway to slow the airplane down. During the landing roll up this hill, the right wing struck trees and spun the airplane around 180 degrees.

During the post crash inspection of the engine, the exhaust valve for the number three cylinder was found broken.