“During cruise flight, a loud bang from the engine compartment was followed by a loss of power and significant engine vibration,” states the submitter. “The pilot made an emergency landing on a dirt road with no damage to the aircraft. The number one cylinder head had fractured completely through, just above the cylinder barrel heads, leaving a one-half inch gap between head fins numbers 6 and 7. The cylinder had been repaired 212 hours prior to failure and had been bored to .010 oversize. A serviceable tag had been provided by the repair station that performed the work.”

Part Total Time: unknown.