As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN LEVEL FLIGHT, CREW REPORTED HEARING A RUMBLE LASTING 20 SECONDS. UPON LANDING, CREW NOTICED AFT LAVATORY SERVICE DOOR AND FORWARD 1/3 OF SURROUNDING BELLY PANEL MISSING. FURTHER INSP REVEALED SCORING ON SURROUNDING FAIRINGS AND DAMAGED ANTENNAS. ROOT CAUSE DETERMINED TO BE FOD THROWN FROM NOSE WHEEL ON TAKEOFF WHICH DEFORMED PANEL ALLOWING AIR LOADS TO OPEN SERVICE DOOR.