What was found
(CAN) AFTER TAKEOFF WITH CRUISE POWER SELECTED, THERE WAS SEVERE VIBRATION FROM THE LEFT HAND ENGINE. SMOKE, FLAMES, AND OIL WERE SEEN COMING FROM THE ENGINE COWLING. THE ENGINE WAS SHUT DOWN. POST-FLIGHT INSPECTION FOUND THERE WERE TWO HOLES IN THE UPPER ENGINE CASE, ONE BETWEEN NR 5 AND NR 6 CYLINDERS, THE OTHER BETWEEN NR 1 AND NR 2 CYLINDERS.