Cessna T210R N6209U accident near Grove City, Pennsylvania

Probable cause

A catastrophic engine failure due to oil starvation after the pilot’s failure to secure the oil filler cap before flight. Contributing to the accident was the pilots’ decision to continue the flight following the oil loss event and precautionary landing.

NTSB analysis

During the visual flight rules cross-country flight, the pilot and pilot-rated passenger, who was also an aircraft mechanic, diverted due to an oil pressure issue. Witnesses at the diversion airport stated that, after landing, the pilot requested 6 quarts of oil and rags to clean his airplane. The airplane was “covered” with oil on the fuselage, wings, and engine cowling. The pilot stated that the oil loss was the result of an unsecured oil filler cap. After servicing the airplane with all 6 quarts of oil and cleaning the residual oil off the airplane, the pilots departed. A witness reported that the airplane’s engine made “abnormal cracking and popping” noises during engine start and taxi, and that the pilots departed without performing an engine run-up.

About 15 minutes after departure, while cruising at 4,500 ft mean sea level (msl), the pilot reported a loss of engine power to air traffic control and was given vectors to a nearby airport; however, he was unable to glide to the airport and the airplane impacted trees and steep terrain. A significant post-impact fire ensued. Postaccident examination of the wreckage revealed that the engine exhibited features consistent with a loss of oil lubrication. Although several of the crankcase through-bolts were missing their respective nuts, this was likely the result of postimpact thermal damage rather than improperly secured nuts.

Based on the available information, it is likely that the internal components of the engine sustained damage due to oil starvation after the pilot failed to secure the oil filler cap. This damage was sufficient to result in catastrophic engine failure when the engine continued to be operated, even after adding oil. The pilots’ decision to depart on the accident flight without further examining the engine for signs of damage or conducting an engine run-up contributed to the accident.

Text from the NTSB. Open the NTSB docket for ERA22FA076 for the full record.