What was found
ENGINE FAILURE - LEVEL AT 12,000 FEET MSL CRUISE POWER. RAPID REDUCTION IN RPM, M.A.P., AND O.P., THEN PUT IN FEATHER. UPON LANDING, MECHANIC DETERMINED THAT NR 1 AND NR 2 CYLINDERS PISTONS DO NOT MOVE WHEN CRANKSHAFT/PROPELLER IS ROTATED. ALTHOUGH THE ENGINE HAS YET TO BE DISASSEMBLED, IT CAN BE ASSUMED THE CRANKSHAFT IS PROBABLY BROKEN AT A REAR MAIN JOURNAL.