As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT MADE AN EMERGENCY OFF AIRPORT LANDING AFTER EXPERIENCING A LOUD BANG FOLLOWED BY A LOSS OF ENGINE POWER AND SMOKE. INSPECTION OF THE ENGINE REVEALED A CRACK OF APPROXIMATELY 4 INCHES ON THE CRANKCASE STARTING FROM UNDER THE NR 3 CYLINDER FLANGE AT ABOUT THE 10 O'CLOCK POSITION, UPWARDS PAST THE FRONT OF THE OIL PRESSURE RELIEF VALVE PAD, TOWARD THE UPPER CRANKCASE FLANGE HALF.