As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING POST FLIGHT WALK AROUND THE PILOT NOTICED THE IB GEAR DOOR WAS IN THE DOWN POSITION, AFTER FURTHER INSPECTION IT WAS NOTICED THAT THE GEAR DOOR ACUATOR PISTON SHAFT WHERE IT IS THREADED HAD SNAPPED OFF. THERE WAS NO OTHER DAMAGE TO THE A/C. AFTER FURTHER INSPECTION THERE APPEARED TO BE A OLD CRACK APPROX HALFWAY THROUGH THE SHAFT WHICH WOULD NOT BE NOTICABLE DURING ROUTINE INSPECTIONS.