What was found
FLIGHT CREW NOTICED THE RIGHT HYDRAULIC SYSTEM HAD LOST ALL FLUID AND PRESSURE WHILE AT CRUISE. COM PROCEDURES WERE COMPLIED WITH AND VERIFIED SYSTEM INOPERATIVE. THE FLIGHT RETURNED TO A NORMAL SAFE LANDING BACK AT DEPARTURE AIRPORT AND WAS TOWED TO THE GATE. MAINTENANCE AT DTW FOUND THE RT HYDRAULIC SYSTEM VACUUM BREAKER VALVE LEAKING AND REPLACED IT. STANDARD COMPONENT REPLACEMENT DUE TO LOSS OF FLUID ALSO ACCOMPLISHED. FUNCTIONAL CHECKS OF RELATED SYSTEMS, INCLUDING GEAR SWINGS, PERFORMED SATISFACTORILY, LEAK CHECKS WERE ALL GOOD, AND THE AIRCRAFT WAS RETURNED TO SERVICE.