N21415Cessna 182P · 1972

On October 5, 2010, about 1545 eastern daylight time, a Cessna 182P, N21415, operated by Westmoreland Patterson Moseley & Hinson LLP., was substantially damaged during a forced landing, after it experienced a total loss of engine power after takeoff from the Columbia Metropolitan Airport (CAE), Columbia, South Carolina. The certificated commercial pilot sustained minor injuries and a passenger was not injured. Visual meteorological conditions prevailed and an instrument flight rules flight plan had been filed for the flight destined to the Middle Georgia Regional Airport (MCN), Macon, Georgia. The business flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91.

The pilot reported that he flew with the passenger from MCN to CAE earlier in the day without incident, and they were returning to MCN when the accident occurred. After takeoff, the pilot contacted departure control and was subsequently cleared to fly direct to MCN. Shortly thereafter, the pilot noted that the oil pressure gauge was below the green arc, and he elected to return to CAE. He also noted some smoke in the cockpit, which was followed by a complete loss of engine power. The pilot initiated a forced landing to a highway, about 1000 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 airplane was equipped with a Continental Motors O-470-R series engine. Initial examination of the engine 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. In addition, the oil filler cap was loose. The pilot reported that no oil had been added to the engine prior to the flight, and 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 retained for further examination.

The engine was disassembled at the manufacturer's facility under the supervision of an FAA inspector. The disassembly revealed that the Nos. 1, 3, and 5 cylinder pistons and rings exhibited damage and 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 that was adjacent to the oil suction tube screen exhibited signatures of substantial material accumulation [A detailed teardown report with accompanying photographs is contained in the public docket for this accident]. The six pistons with rings, and fragments from the oil sump were forwarded to the NTSB Materials Laboratory, Washington, DC, for further examination.

Examination of the retained components by an NTSB metallurgist revealed 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 and approximately 75 percent was recovered. The visible fractures displayed features consistent with brittle overstress; however, burnishing obliterated many of the 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. [A detailed Materials Laboratory Factual report with accompanying photographs is contained in the public docket for this accident].

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, which included 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 has been operated for approximately 1,397 total hours. At the time of the accident, the engine had been operated for about 1,480 hours since new and 266 hours since the cylinders were replaced.