What was found
(CAN) (COPY OF PILOT IN COMMAND FLIGHT OCCURRENCE REPORT: JUST AFTER DEPARTURE, WHEN GEAR WAS SELECTED UP, RT GEAR DOOR UNSAFE LIGHT (YELLOW) FLICKERED ON SEVERAL TIMES. THE GEAR WAS RECYCLED WITHOUT SUCCESS. THE FLIGHT RETURNED FOR LANDING AT CPH. AFTER GEAR DOWN SELECTED BEFORE LANDING, THE GEAR DOOR UNSAFE LIGHT REMAINED ON. RT REAR DOOR SENSOR GAP WAS MEASURED AS OUT OF TOLERANCE. MAINTENANCE RE-RIGGED GAP AND NO FURTHER PROBLEMS. GEAR OPERATIONAL CHECKS CARRIED OUT AND INDICATIONS ARE NORMAL, A/CA RETURNED TO SERVICE.