N8948TCessna 182C · 1960

On January 23, 2010, about 1500 Pacific standard time, a Cessna 182C airplane, N8948T, was substantially damaged during a forced landing near Reno, Nevada. The airplane was registered to Alpine Aviation Partners LLC of Reno, and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. The private pilot and passenger sustained minor injuries. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight. The local flight originated from the Reno-Stead Airport (4SD), about 1415.

In a written statement, the pilot reported that during cruise flight, the airplane experienced a “significant shake” similar to a “small strike.” The pilot verified his instruments, noticed the “manifold pressure jumping,” and noted that it felt like the engine was losing power. The pilot applied carburetor heat, checked the fuel selector handle, and reduced the engine power and initiated a precautionary landing to a road. The pilot stated that during the descent and on a base leg to his selected landing area, the “engine failed completely.” Despite his attempts, the engine would not restart and the propeller would not move. Subsequently, the pilot landed on an unoccupied road. During the landing roll, the airplane struck a ditch and nosed over.

Examination of the airplane by the pilot revealed that oil was visible on both sides of the fuselage and wing flaps. The top portion of the vertical stabilizer and rudder were bent and buckled. Buckling in the fuselage was observed just forward of the empennage.

The Continental O-470-L engine, serial number 82178-4-L, was examined at the facilities of Teledyne Continental Motors under the supervision of the Safety Board investigator-in-charge (IIC). Examination of the engine revealed that the number one connecting rod exhibited extreme thermal and mechanical damage and was fractured through at the base of the I-beam. Fragments of the number one connecting rod cap exhibited thermal and mechanical damage. The number two connecting rod exhibited extreme thermal and mechanical damage and the bearing supports were distorted. The number two connecting rod cap exhibited thermal and mechanical damage and was deformed.

The oil sump exhibited impact damage. About five quarts of oil was drained from the oil sump. The oil was dark in color and contained portions of what appeared to be a paper towel and fragments of damaged internal engine components. The oil pickup tube was intact and undamaged. The oil pickup tube was restricted with a paper-towel-like material.

The crankcase exhibited exterior damage concentrated above the number two cylinder bay. The number one and two cylinder bays exhibited mechanical damage at the centerline of the cylinder bore that displaced the intake lifter bore material from the crankcase casting. The remaining cylinder bays were intact and undamaged. The main bearing support mating surfaces were intact and exhibited no signs of fretting or bearing tang lock-slot elongation. The main bearing support diameters were intact and exhibited no signs of bearing movement or rotation. The oil galleys and passages in the left and right crankcase halves were intact, clear and unrestricted.

The rear crankshaft main bearing exhibited lubrication distress and thermal smearing of the surface babbit. The number two intermediate crankshaft main bearings exhibited lubrication distress and thermal smearing of the surface babbit, exposing the copper layer. The number three intermediate crankshaft main bearings exhibited contamination imbedded in the surface layer. The front crankshaft main bearings exhibited contamination imbedded in the surface layer.

The pilot reported that the engine had accumulated a total time in service of 3,039 hours, with 993 since last overhaul.