Abstract: The present invention provides a slotted cam control system for controlling pitch angles of fan blades of a relatively low-pressure-ratio fan within a fuselage of a helicopter. The stream of air generated by the fan is directed into the tailboom of the helicopter, and is selectively discharged through the circulation control tailboom and left and right openings of a direct jet thruster. A force-receiving arm of a slotted cam control system receives left and right forces from corresponding left and right foot rudder pedals. An end of the force-receiving arm fits into a V-shaped cam. When the pilot depressed a left foot rudder pedal and releases a right foot rudder pedal, for example, the end of the force receiving-arm is first moved along a first predetermined distance of the V-shaped cam in order to decrease the pitch angles of the fan blades while the opening of the direct jet thruster corresponding to the released foot rudder pedal is closed.