What was found
(CAN) AFTER GETTING AIRBORNE, THE ACFT ENCOUNTERED AN AIR WING LEAK IN CRUISE. IN CONSULTATION WITH MAINTENANCE, THE FLIGHT CREW RETURNED THE ACFT. THE LANDING WAS UNEVENTFUL WITH NO ADVERSE PASSENGER REACTION. THE ACFT WAS TAKEN OFFLINE AND A NEW ACFT WAS UTILIZED FOR THE SUBSEQUENT DEPARTURE. RESOLUTION DUCT ASSY AND DUCT REPLACED IAW AMM 36-12-41, PB 400. SENSE LOOP RE- INSTALLED AND LEAK CHECK C/O. NO FAULT FOUND, SERVICEABLE.