As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE IN CRUISE FLIGHT THE LT ENGINE COWLING DEPARTED THE AIRCRAFT. THE COWLING'S WAS NOT RECOVERED, FLIGHT WAS OVER WATER. AN UNEVENTFUL LANDING WAS MADE. SINCE THE FLIGHT WAS OVER WATER IT COULD NOT BE DETERMINED WHY THE COWLINGS DEPARTED THE AIRCRAFT.