As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
OPERATOR COMPLAINED OF ROUGHNESS ON TAKEOFF. AIRCRAFT RETURNED TO HANGAR WITH OIL LEAKING FROM COWLING. REMOVED TOP COWLING AND FOUND NR 6 CYLINDER SEPARATED 1 INCH TO 2 INCHES BELOW HEAD. COULD FIND NO EVIDENCE OF PRIOR DAMAGE. (NOTE: CYLINDER WAS REPAIRED 454.0 HOURS PREVIOUSLY FOR OIL CONSUMPTION.) SUSPECT CAUSE COULD BE FATIGUE OR HIDDEN DEFECT. REPLACED CYLINDER AND PISTON ASSY.