LAX08LA153

During an instrument flight rules cross-country flight at 16,000 feet msl, the pilot reported to air traffic control that he had a total loss of engine power and was attempting to land at an airport about 12 miles from his current position. The pilot was unable reach the airport, and while trying to land on the desert floor, one of the main landing gear wheels hit a cactus and the airplane nosed over. During the recovery of the airplane, internal components of the engine where found in the debris field. The time recorded on the engine at the last annual inspection was 978 hours since major overhaul. A review of the airplane logbooks revealed that a top overhaul was completed on March 21, 2007, which included all 6 cylinders being removed, overhauled, and replaced. The engine failure occurred 120 hours since completion of the top overhaul. During the engine examinations, thermal discoloration of the crankshaft main journals and damage to various other internal components were noted. The crankshaft was fractured just forward of the number 2 main bearing. The number 2 main bearing was not located; however, the bearing support exhibited evidence of bearing shift, tang slot elongation, and rotation. The crankshaft main bearings and the connecting rod bearings were also damaged as a result of oil starvation, due to the number 2 main bearing rotation. The crankcase itself had been compromised just above the numbers 3 and 4 cylinders. The crankshaft was metallurgically examined at a laboratory. The crankshaft chemistry, case depth, surface hardness, and core hardness met specifications. The fracture initiated at the surface adjacent to the number 2 main bearing and progressed toward the number 3 rod journal in fatigue.

HISTORY OF FLIGHT On May 23, 2008, about 1150 mountain standard time (MST), a Cessna P210N, N4753K, experienced a total loss of engine power during cruise flight and collided with the terrain during the forced landing near Peach Springs, Arizona. The owner/pilot was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The certificated private pilot was not injured; the airplane sustained substantial damage to both wings by impact forces. The cross-country personal flight departed Grand Canyon National Park Airport, Grand Canyon, Arizona, about 1100, with a planned destination of Bullhead City, Arizona. Visual meteorological conditions prevailed, and an instrument flight rules (IFR) flight plan had been filed. The pilot reported that while flying at 16,000 feet mean sea level (msl), the engine experienced a total loss of power. He reported to air traffic control (ATC) that he was going to try and land at Grand Canyon Caverns Airport (L37), about 12 miles from his current position. The pilot was unable to reach the airport. While trying to land on the desert, one of the main landing gear wheels hit a cactus, and the airplane nosed over. During the recovery of the airplane, it was observed that internal components of the engine where found in the debris field. The airplane was recovered for further examination. AIRCRAFT INFORMATION The airplane was a 1979 Cessna P210N, serial number 21000284. A review of the airplane's logbooks revealed that the airplane had a total airframe time of 2,950 hours at the last annual inspection. The logbooks contained an entry for the annual inspection dated October 4, 2007. The tachometer read 1,483.6 at the last inspection. The tachometer read 1,519.6 at the accident site. The engine was a Teledyne Continental Motors (TCM) TSIO-520-P5B, serial number 278661-R. Total time recorded on the engine at the last annual inspection was 978 hours since major overhaul. A review of the airplane logbooks revealed that on March 21, 2007, a field top overhaul was completed, which included removing all 6 cylinders, overhauling the cylinders, and reinstalling the cylinders on the engine. The tachometer reading was recorded in the logbook write-up as 1,399.2 hours. The engine failure occurred 120 hours after the overhaul. TESTS AND RESEARCH During the engine teardown inspection, thermal discoloration was noted to the main journals of the crankshaft, as well as damage to the counterweight hanger blade. The crankshaft separated forward of the number two main journal, and the number two main bearing was not found during the inspection. It was the decision of the Safety Board to continue the engine inspection at the TCM Analytical Department, Mobile, Alabama. During the inspection, it was noted that the crankshaft exhibited a fracture just forward of the number 2 main bearing journal. The crankshaft main bearings and connecting rod bearings exhibited signatures of lubrication distress. The number 2main bearing support exhibited signatures of bearing shift, tang slot elongation, and rotation. The crankcase exhibited an approximate 4- by 6-inch breach of the crankcase above both the number 3 and number 4 cylinders. The crankshaft fracture was sectioned and forwarded to the TCM Metallurgical Laboratory for further examination. On December 12, 2008, the TCM Metallurgical Laboratory conducted an examination of the crankshaft fracture. Hardness at the journal surface measured 70R30N, which met specification. The sectioned piece perpendicular to the surface showed a case depth of .020 and a core hardness of 35 HRC, both which meet specification. The fracture surface indicated the fracture initiated at the surface adjacent to the number 2 main bearing and progressed toward the number 3 rod journal in fatigue. Much of the fracture surface was damaged, presumably due to continued operation during and after separation.