What was found
(CAN) ENGINE EXPERIENCED A SUDDEN STOPPAGE IN FLIGHT. ACFT WAS LANDED AND THE ENGINE WAS REMOVED AND SHIPPED TO US. UPON DISASSEMBLY AND INSPECTION IT WAS FOUND THAT THE NR 4 CYLINDER FAILED FROM A CRACK THAT PROGRESSED FROM NEAR THE TOP OF THE BARREL ALMOST ALL THE WAY AROUND THE CIRCUMFERENCE OF THE BARREL. THIS FAILURE SEIZED THE ENGINE. THIS CYLINDER APPEARS TO BE A FIELD O/H UNIT AND HAS BEEN SENT TO TSB FOR INSPECTION.