Cessna 182M N777RK accident near Upland, California

Probable cause

The total loss of engine power due to detonation within the No. 2 cylinder as a result of a lean fuel flow setting.

NTSB analysis

The pilot reported that during takeoff, as the airplane ascended through about 250 ft above ground level, the engine began to sputter, and he initiated a left turn in an attempt to return to the airport. Shortly after, the engine lost all power, and the pilot initiated a forced landing to an open area near the departure runway on airport property. During landing, the airplane bounced, became airborne, and traveled across a road before it landed in a parking lot, impacted trees, and came to rest upright.

Examination of the engine revealed that the No. 2 cylinder would not produce compression. Further examination and removal of the cylinder revealed evidence of detonation on the piston and cylinder head. Due to impact damage sustained to the airplane, throttle, mixture, and propeller control travel limits could not be determined. Downloaded data from the engine monitoring unit revealed evidence of a low fuel flow rate for takeoff about, or about 8 to 10 gallons per hour below the calculated takeoff fuel burn rate. Recorded data from the two previous flights before the accident flight indicated that the No. 2 cylinder produced temperatures higher than the manufacturer’s maximum cylinder head temperature limit. Postaccident testing of the carburetor showed that the carburetor fuel flow rate was slightly higher than the specification and would not have contributed to detonation. It’s likely that the detonation occurred as a result of the reduced fuel flow and lean fuel to air mixture, however, the reason for the reduced fuel flow rate could not be determined.

Text from the NTSB. Open the NTSB docket for WPR19LA174 for the full record.