Apparatus for selectively varying air resistance on a land transport

Abstract

An apparatus for selectively varying air resistance on a land transport vehicle to optimize reduction of drag except when drag is desirable as a speed reduction aid. The vehicle typically includes a cab and at least one trailing cargo container. First and second wings are mounted on respective vertical axes on opposite sides of the cab adjacent the rear. Means are provided for moving the wings when desired between a first, relatively low drag position wherein the wings lie substantially flush with the sides of the cab and a second, relatively high drag position wherein the wings project outwardly beyond the sides of the cab and into the air system moving past the cab to increase drag and reduce the braking distance of the vehicle. An air deflector is mounted on the roof of the cab to normally deflect air over the top of the cargo container. The air deflector includes a relatively large opening therein for allowing air to freely pass therethrough and a door positioned in the opening and mounted for movement relative to the door. Means move the door between a first, relatively low drag position wherein the door covers the opening and air is deflected up and over the cargo container and a second, relatively high drag position wherein the door is retracted away from the opening and air is permitted to flow directly through the opening and against the forward end and top of the cargo container.