As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING CLIMBOUT THE #1 ENGINE HAD A LOSS OF POWER FOLLOWED BY ROUGH RUNNING. ON RETURN TO THE AIRPORT OIL WAS NOTICED ESCAPING THROUGH THE #1 ENGINE COWLING. POST FLIGHT INSPECTION FOUND THE #1 CYLINDER HEAD LYING IN THE COWLING. THE CYLINDER WAS REMOVED; THE OIL DRAINED; THE ENGINE AND FILTERS WERE CHECKED FOR DAMAGE. A NEW #1 CYLINDER WAS INSTALLED AND THE AIRCRAFT RETURNED TO SERVICE.