What was found
DURING DECENT TO AIRPORT, PILOT REPORTED RT ENGINE STARTED HAVING EXCESSIVE VIBRATION. NO OTHER MAJOR ENGINE INDICATIONS WERE NOTED. AFTER LANDING, A MAGNETO CHECK WAS CONDUCTED AND NO DESCREPANCIES WERE FOUND. UPON REMOVAL OF COWLING, RT ENGINE NR 6 CYLINDER WAS FOUND TO HAVE CRACKED AROUND THE CIRCUMFERENCE OF CYLINDER HEAD AT THE NR 9 AND 10 COOLING FIN, COMPLETELY SEPARATING THE CYLINDER HEAD FROM THE BARREL AT THE VERY TOP OF STEEL CYLINDER BARREL. AFTER RESEARCHING AD, AMENDMENT, THE CYLINDER ASSY WAS FOUND NOT TO APPLY DUE TO S/N OF CYLINDER AND THE PRESENCE OF THE (A) STAMPED ON THE ROCKER BOX FLANGE. (K)