What was found
ON APPROACH TO DCA THERE WAS NOT A RT MAIN LANDING GEAR DOWN AND LOCKED INDICATION WHEN THE LANDING GEAR WAS SELECTED DOWN. THE CREW REFERENCED THE QRH AND AN EMERGENCY WAS DECLARED. THE AIRCRAFT LANDED SAFELY IN DCA. MAINTENANCE INSPECTED AND REPLACED THE RT MAIN LANDING GEAR DOWN LOCKED INDICATION BULBS IN ACCORDANCE WITH DORNIER. MAINTENANCE MANUAL 32-61-12. OPERATIONAL CHECKS WERE COMPLETED AND THE AIRCRAFT RELEASED FOR SERVICE.