DEN05LA143

The airplane was eastbound and descending from a cruising altitude of 13,500 feet for landing. The pilot said that during descent, the "cylinder number 1 failed, followed immediately by the failure of cylinder number 2, and within about 4 seconds a total seizure of the engine." The pilot made a forced landing in an alfalfa field, subsequently impacting a berm and substantially damaging the airplane. The engine was later disassembled and examined. The engine had seized and could not be turned because connecting rods 1, 2, 3, 4, 7, and 9 were found broken, and numbers 5 and 6 were found severely damaged. Connecting rod 8 was not broken or damaged. Metal contamination was noted in the push rod housings, oil sump, thrust cover and bearing; cam, cam rollers, cam drive gear and inspection hole; main case, and oil screen. According to the FAA inspector, there were indications that the #7 connecting rod had struck the crankcase between #6 and #7 cylinders, breaking the through bolts.

On September 19, 2005, approximately 1745 mountain daylight time, a North American SNJ-5, N212TC, piloted by a private pilot, was substantially damaged when it impacted terrain during an off-airport forced landing just east of the Torrington Municipal Airport (TOR), Torrington, Wyoming. Visual meteorological conditions prevailed at the time of the accident. The personal cross-country flight was being conducted under Title 14 CFR Part 91 without a flight plan. The pilot reported no injuries. The flight originated in Ogden (OGD), Utah, approximately 1500, and was en route to Scottsbluff (BFF), Nebraska.

According to the Aircraft Accident Report Form 6120.1/2 submitted by the pilot, he was eastbound and descending from a cruising altitude of 13,500 feet for landing at Scottsbluff, Nebraska. During the descent, the "cylinder number 1 failed followed immediately by the failure of cylinder number 2 and within about 4 seconds a total seizure of the engine." The pilot made a forced landing in an alfalfa field approximately 2 miles east of TOR. During the landing, the airplane impacted a berm that separated the left main landing gear and wrinkled the left wing. According to a Federal Aviation Administrationn (FAA) inspector, the left wing was wrinkled, one blade on the propeller was bent, and the right main gear and wheel were destroyed.

On December 24, 2005, the engine was disassembled and examined at Tulsa Aircraft Engines, Inc., Tulsa, Oklahoma, under the direction of the FAA. The engine had seized and could not be turned because connecting rods 1, 2, 3, 4, 7, and 9 were found broken, and numbers 5 and 6 were found severely damaged. Connecting rod 8 was not broken or damaged. Metal contamination was noted in the push rod housings, oil sump, thrust cover and bearing; cam, cam rollers, cam drive gear and inspection hole; main case, and oil screen. According to the FAA inspector's report, there were indications that the #7 connecting rod had struck the crankcase between #6 and #7 cylinders, breaking the through bolts.