Abstract: The invention comprises a set of tubular inflatable bags mounted to the underside of a transport trailer along its lower edge in front of the rear wheel assembly. The bags are pressurized by ram air inflation upon forward motion of the trailer, such that they prevent air from entering the rear wheel assembly and thereby reduce aerodynamic drag. The outer exposed sides of the bags are vertically and horizontally straightened and stiffened by horizontal ribs which are anchored by cords to the trailer. The apparatus gives way without stress when unpressurized at slow speed and when docking to avoid damage.

Abstract: The invention comprises a set of tubular inflatable bags mounted to the underside of a transport trailer along its lower edge in front of the rear wheel assembly. The bags are pressurized by ram air inflation upon forward motion of the trailer, such that they prevent air from entering the rear wheel assembly and thereby reduce aerodynamic drag. The outer exposed sides of the bags are vertically and horizontally straightened and stiffened by horizontal ribs which are anchored by cords to the trailer. The apparatus gives way without stress when unpressurized at slow speed and when docking to avoid damage.

Abstract: The invention comprises a set of tubular inflatable bags mounted to the underside of a transport trailer along its lower edge in front of the rear wheel assembly. The bags are pressurized by ram air inflation upon forward motion of the trailer, such that they prevent air from entering the rear wheel assembly and thereby reduce aerodynamic drag. The outer exposed sides of the bags are vertically and horizontally straightened and stiffened by horizontal ribs which are anchored by cords to the trailer. The apparatus gives way without stress when unpressurized at slow speed and when docking to avoid damage.

Abstract: The invention comprises a set of tubular inflatable bags mounted to the underside of a transport trailer along its lower edge in front of the rear wheel assembly. The bags are pressurized by ram air inflation upon forward motion of the trailer, such that they prevent air from entering the rear wheel assembly and thereby reduce aerodynamic drag. The outer exposed sides of the bags are vertically and horizontally straightened and stiffened by horizontal ribs which are anchored by cords to the trailer. The apparatus gives way without stress when unpressurized at slow speed and when docking to avoid damage.

Abstract: A twin bag inflatable rear airfoil for truck or transport trailer with attached shelves that bridge the surface gap between the trailer side and top surfaces, and the corresponding side and top surfaces of the inflatable bags. Shelves also bridge the upper surface gap between the two bags and provide a platform to deploy a collapsible yaw control fin. Another set of panels provide airfoil surfaces in the ground domain and are integral to the organised automatic folding and stowage of the apparatus. Interrupted ribs stiffen the inflatable surfaces while allowing them to fold in an orderly manner.

Abstract: The invention comprises an inflatable bag mounted on each of the rear trailer doors of a standard tractor-trailer unit. The optimum aerodynamic shape of the bags with stable flat external surfaces for air to pass over is created by a series of internal cords extending horizontally in a radial array from the medial edge of the base of each bag to its corresponding lateral surface, and vertically form the top to the bottom surfaces of each bag.