Cessna 172RG N6117R accident near Rockaway, New Jersey

Probable cause

A total loss of engine power due to oil starvation for undetermined reasons.

NTSB analysis

The certificated flight instructor (CFI) and dual/student pilot were practicing maneuvers when the CFI noticed that the left main gear of the airplane was wet. As he looked for the source of the substance he noticed that the airplane’s oil pressure was critically low and immediately headed back to the airplane’s base. On the way, the engine came “to a halt with the propeller stopping” and the CFI elected to land in an empty section of a mall parking lot. The airplane’s nose landing gear contacted a curb and the right wing impacted a tree before coming to a stop. An examination of the wreckage revealed the fluid on the wheel to be oil leaking from the engine, which covered the bottom and empennage section of the airplane. A teardown examination of the engine found the No. 3 and No. 4 pistons with damage consistent with overheating and oil starvation. The lower portion of the No. 3 piston was destroyed. There was no internal or external evidence with the engine to account for the oil leak. The engine oil system was examined and found to be unremarkable. The CFI stated that a quart of oil was added, for a total 6.7 quarts of oil in the engine, prior to the accident flight.

Text from the NTSB. Open the NTSB docket for ERA09LA481 for the full record.