Abstract: A flexible duct for conveying a gaseous flow, with the duct useable as the flexible nozzle in a wind tunnel. The duct includes a flexible plate member which is attached at the downstream end to a frame support member, with the upstream end of the flexible plate member being slideable and pivotable upon a member attached to the frame support member. A plurality of swing link members in spaced-apart relationship are pivotally connected at one end to the flexible plate member, and pivotally connected at the other end to a translatable and rotatable cradle-like member which is supported by crank members from the frame support member. An actuator is used to selectively move the cradle-like member. The resultant movement of the cradle-like member causes the flexible plate member to deflect, resulting in predetermined contours (and profiles) of the flexible plate member.