Cessna 182 N2861R accident near Gainesville, Florida

Probable cause

The failure of the engine crankshaft near the Nos. 4 and 5 crankshaft journals due to oil starvation. The reason for the oil starvation could not be determined during postaccident examination.

NTSB analysis

The commercial pilot stated that, before takeoff, he conducted a preflight inspection of the airplane and added 1 quart of oil to make a total of 8 quarts of oil in the airplane; the engine runup was normal. He further stated that the approximate 2-hour flight was uneventful until after he was cleared to land, when the engine began to run "rough." He enriched the mixture and reduced power, but the engine began shaking, oil sprayed onto the windshield, and then the engine lost total power. He declared an emergency and conducted a forced landing on a road, during which the left wing impacted a tree.

An examination of the engine revealed that the crankshaft's Nos. 4 and 5 connecting rod journals exhibited discoloration and heat damage, consistent with oil starvation, and that the rods had separated from the crankcases at their respective journals. The main bearing support mating surfaces were intact and exhibited no signs of fretting, bearing movement, or bearing rotation. The oil galleys and passages in the crankshaft and engine case halves were clear and unrestricted. Although an unmeasured quantity of oil was noted in the engine's oil sump, due to the damage of the sump and crankcase, the quantity of oil in the engine before the accident could not be determined.

Text from the NTSB. Open the NTSB docket for ERA16LA114 for the full record.