Rear-mounted aerodynamic structure for truck cargo bodies

This invention provides a foldable/retractable and unfoldable/deployable, rearwardly tapered aerodynamic assembly for use on the rear trailer bodies and other vehicles that accommodate dual swing-out doors. The aerodynamic assembly includes a right half mounted on the right hand door and a left half mounted on a left hand door. Each half is constructed with a side panel, top panel and bottom panel, which each form half of an overall tapered box when deployed on the rear of the vehicle, the bottom panels and top panels being sealed together at a pair of overlapping weather seals along the centerline. The panels are relatively thin, but durable, and are joined to each other by resilient strip hinges. The top and bottom panels are also hinged to form two sections along diagonal lines to facilitate folding of all panels in a relatively low-profile stacked orientation. This low profile allows the doors to be swung through approximately 270 degrees to be secured to the sides of the body in a manner that does not interfere with adjacent doors or bodies in, for example a multi-bay loading dock. A swing arm assembly and gas spring biases the panels into a deployed position that can be refolded by grasping the side panel and rotating it inward toward the door surface. The top and bottom panels are partly inwardly folded when deployed to define external valleys using a stop assembly. This ensures that the panels fold readily when desired without the two sections of the panels "locking up".