CEN18LA174

The pilot reported that he had departed on a local flight and leveled the airplane at 2,600 ft mean sea level when he observed a drop in engine rpm and heard a "thumping" sound from the engine. The pilot reversed course to return to the airport; the noise increased, he smelled burning oil, and the engine subsequently quit. The pilot conducted a forced landing to a field, during which the nose landing gear collapsed and the wings sustained substantial damage. An examination of the airplane revealed no oil on the engine dipstick; however, oil was coming out of the oil cooler, and oil was visible on the right side of the cowling. Maintenance records indicated that the engine, including the oil cooler, was new and had been installed about 8 hours before the accident flight. An examination of the oil cooler revealed that the leak came from between the plates forming the oil circuit; it was likely due to a defect in the brazed joint between the plates. The engine lost power due to oil starvation.

On May 15, 2018, at 1455 eastern daylight time, a Cessna 177 airplane, N9058F, was substantially damaged during a forced landing near Fort Wayne, Indiana. The commercial pilot and passenger were not injured. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight, which was operated on an instrument flight rules flight plan. The local flight originated from the Smith Field Airport (SMD), Fort Wayne, Indiana, at 1453.The pilot reported that shortly after takeoff as he leveled the airplane at 2,600 ft mean sea level, the engine rpm began decreasing and he heard a "thumping" noise in the engine. He lowered the nose of the airplane to maintain 80 mph and turned back toward the airport. The thumping noise increased, and he smelled burning oil just before the engine quit. The pilot selected a field for a forced landing and as he approached the field, he banked to the left to avoid overrunning the field. As he banked, the left wingtip contacted the ground and the airplane slid sideways collapsing the nose landing gear. Both wings sustained substantial damage. According to the responding Federal Aviation Administration Inspector, an examination of the engine revealed no oil on the engine oil dip stick. Oil was visible on the right side of the cowling and oil was coming from the oil cooler. According to the maintenance records, the engine, including the oil cooler, was new and had been installed about 8 hours prior to the accident flight. The oil cooler was sent to the National Transportation Safety Board Materials Laboratory in Washington, DC, for further examination. Examination of the oil cooler revealed that the leak came from between the plates forming the third oil circuit from the bottom. There was no evidence of mechanical damage from an external source and no evidence of bulging or other distortions.