What was found
AS CREW WAS RETRACTING THE FLAPS, RECEIVED A MASTER CAUTION FLAP FAIL MESSAGE. CREW RAN QRH, DECLARED AN EMERGENCY AND ELECTED TO RETURN TO DEPARTURE. LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED AND FOUND THE RT TORQUE TUBE HAD FALLEN OFF INBD SIDE OF THE NR 3 FLAP ACTUATOR. MAINTENANCE RECONNECTED TORQUE TUBE IAW AMM AND OPS CHECKED GOOD.