Cessna 182 N3537C accident near Lebanon, Ohio

Probable cause

Improper maintenance that resulted in a blocked crankcase breather port and a subsequent total loss of engine power.

NTSB analysis

The pilot and passenger were on a cross-country flight after maintenance personnel installed new avionics in the airplane. While at cruise altitude, the engine began to knock and vibrate and subsequently the engine lost all power. The pilot was unable to maintain altitude or reach an airport and landed the airplane in a field. The airplane overran the field and impacted trees; the wings and fuselage sustained substantial damage.

The wreckage was examined, and a plastic cap was found installed on the engine crankcase breather port; the engine crankcase seal was found dislodged. Oil was found on the underside of the engine compartment and cowling. The blocked breather port likely allowed excessive pressure to build up inside the engine and resulted in the dislodged crankcase seal and a loss of oil.

The investigation determined the mechanic who installed the avionics on the airplane also performed maintenance on the engine, which was outside of the repair station’s operations specifications. The mechanic did not have technical data for the work performed on the engine, did not document the work performed, and did not remove the plastic cap from the crankcase breather port following the installation of avionics.

The accident is consistent with a total loss of engine power due to oil starvation as a result of improper maintenance.

Text from the NTSB. Open the NTSB docket for CEN21LA034 for the full record.