What was found
(CAN) AFTER TAKEOFF THE CREW RECEIVED A RT COWL ANTI-ICE DUCT WARNING MESSAGE. THE ACFT RETURNED TO THE DEPARTURE AIRPORT. CONTRACT MAINTENANCE INSPECTED THE ACFT AND FOUND A LOOSE CLAMP AT THE WING ANTI-ICE VALVE. THE CLAMP WAS TIGHTENED AND THE ACFT RETURNED TO SERVICE. THE DEFECT RE-OCCURRED THE NEXT DAY. MAINTENANCE FOUND THE RT COWL ANTI-ICE DUCT OTBD OF THE COWL ANTI-ICE VALVE RUPTURED. THE DUCT WAS REPLACED. COWL ANTI-ICE DUCT, PN 9912190-103, SN 1365, AIPC 30-21-05, FIG 1-5, DUCT TSN 247, CSN 107.