19990329002839A

Acft experienced an engine failure the pilot made an emergency landing in a field, and the acft came to rest inverted, other circumstances are unknown. (From .19) on March 29, 1999, about 1450 hours pacific standard time, a Cessna 172RG, N9451D, sustained substantial damage when it nosed over after an off airport forced landing near moorpark, California. The forced landing was precipitated by catastrophic failure of the engine. The aircraft was owned and operated by ate of California, d.b.a. American flyers, under the provisions of 14 CFR part 91. The flight was a cross-country instrument instructional flight. The aircraft departed montgomery field in san diego, California, about 1315 en-route to Camarillo, California. The instrument flight instructor or private pilot student incurred no injuries. Visual meteorological conditions prevailed and an IFR flight plan was filed. The instructor stated they were in contact with pt. Magu approach control and level at 4,000 feet MSL. After hearing a loud bang in the engine compartment, flames were observed entering the cockpit by the rudder pedals. The instructor immediately turned the fuel selector valve to off and nosed the aircraft over to land. He stated the fire went out and he set up to land in a plowed field. After touchdown, he held the nose up as long as possible. When the nose wheel dropped into the soft dirt, it dug in and the aircraft nosed over. The pilots exited the aircraft without assistance. A federal aviation administration inspector observed that a cylinder had separated from the engine; it and a section of cowling was missing. (-23)on the above date N9451D was at the four thousand feet when the pilot reported a loud bang, loss of power and flames from the engine bay. The pilot shot a emergency landing int a soft plowed field and flipped the aircraft on its bakc. The number 2 engine cylinder separated from the engine casing causing engine failure. No injuries were sustained by the instructor or his student. (.4)the instructor and instrument student were in level flight at 4,000 feet MSL at the initial approach fix for a practice VOR approach. After hearing a loud bang in the engine compartment, smoke and flames were observed entering the cockpit by the rudder pedals. The instructor immediately turned the fuel selector valve to off and nosed the airplane over to land. The fire went out and he set up to land in a plowed field. He secured the airplane, opened the doors, and then executed a soft-field landing with full flaps. When the nose wheel dropped into the soft dirt after touchdown, it dug in and the airplane nosed over. The number two cylinder assembly with its intake and exhaust tubes exited through the cowling and were not recovered. Pieces of piston, compression ring, a push rod, and a piston pin were found in the cowling. The connecting rod fractured at a midpoint along both sides of the wrist pin. Mechanical continuity was established for the remaining engine cylinders, no discoloration was evident, and all fracture surfaces were grainy and angular.