Abstract: An auxiliary air foil device for mounting on a vehicle is disclosed. The air foil device includes an enclosure comprising a base plate, a plurality of side walls, and an air foil panel. The air foil panel is pivotable between an open position and a closed position. In the closed position, the outside air flow will be substantially isolated from the volume within the enclosure. The open position provides access from outside of the enclosure to a volume within the enclosure. An actuator interconnects the underside of the air foil panel with the interior side of the base plate and allows for selective moving of the air foil panel between the open and closed positions. The actuator is pivotably connected to the base plate and the air foil panel, such that as the actuator changes length the rotational position of the air foil panel with respect to the base plate is also changed.