Accident Overview
On October 5, 2010, at approximately 1545 eastern daylight time, a Cessna 182P, registration N21415, operated by Westmoreland Patterson Moseley & Hinson LLP., was substantially damaged during a forced landing. The airplane experienced a total loss of engine power after takeoff from Columbia Metropolitan Airport (CAE) in Columbia, South Carolina. Visual meteorological conditions prevailed, and an instrument flight rules flight plan had been filed for the flight destined for Middle Georgia Regional Airport (MCN) in Macon, Georgia. The business flight was conducted under Title 14 Code of Federal Regulations Part 91.
Flight History
The pilot reported that he and the passenger had flown from MCN to CAE earlier in the day without incident and were returning to MCN when the accident occurred. After takeoff, the pilot contacted departure control and was cleared to fly direct to MCN. Shortly thereafter, the pilot observed the oil pressure gauge below the green arc and decided to return to CAE. He also noticed smoke in the cockpit, which was followed by a complete loss of engine power.
Forced Landing and Damage
The pilot initiated a forced landing to a highway located about 1,000 feet south-southeast of runway 5 at CAE. During the landing, the airplane's right wing struck a pole, and the lower forward portion of the fuselage sustained substantial damage. The pilot sustained minor injuries; the passenger was not injured.
Engine Examination
The airplane was equipped with a Continental Motors O-470-R series engine. Initial examination by a Federal Aviation Administration (FAA) inspector revealed that the crankshaft was seized. Oil streaks were observed on the underside of the engine cowling, and oil was present throughout the engine compartment. Additionally, the oil filler cap was found loose. The pilot reported that no oil had been added to the engine prior to the flight; a preflight check of the oil quantity using the dipstick indicated "just a little less than 10 quarts." A postaccident check of the engine oil level indicated 7.5 quarts.
The engine was disassembled at the manufacturer's facility under FAA supervision. Disassembly revealed damage to the Nos. 1, 3, and 5 cylinder pistons and rings, with signatures of abnormal combustion gas blow-by. The crankshaft, connecting rods, and associated bearings exhibited lubrication distress with associated thermal damage. Piston ring and skirt fragments were found in the oil sump. The area of the sump surface adjacent to the oil suction tube screen showed signatures of substantial material accumulation. Components were sent to the NTSB Materials Laboratory for further examination.
Examination of the retained components by an NTSB metallurgist showed damage to the rings and portions of the piston skirts on the Nos. 1 and 5 pistons. Both oil scraper rings were heavily fragmented. Magnified examination of the ring fractures revealed features consistent with brittle overstress, with no indications of preexisting fractures. The oil control ring for the No. 5 piston was fractured, with approximately 75 percent recovered; visible fractures displayed features consistent with brittle overstress, though burnishing obliterated many fracture faces. The No. 5 oil control ring slot showed extensive thermal erosion, with some locations intersecting the lower compression ring slot. Circumferential fractures on the piston skirts and piston skirt fragments revealed overstress fracture features.
Maintenance Background
According to maintenance records, the engine was manufactured by Continental Motors on March 29, 2007. On April 5, 2010, at a total engine time of about 1,215 hours, all six cylinders, including new pistons and piston rings, were replaced. The airplane's most recent annual inspection was performed on August 10, 2010. At that time, the airframe had accumulated approximately 7,139 hours since new, and the engine had operated for approximately 1,397 total hours. At the time of the accident, the engine had operated for about 1,480 hours since new and 266 hours since the cylinders were replaced.