Abstract: A vehicle streamliner has a balloon or bag member that is supported by a belt member that is tensioned about a generally cylindrical longitudinal perimeter surface of the vehicle. The bag member can be configured for support against an end face area of the vehicle, and preferred shapes for the bag member are disclosed. An array of vortex generators are provided proximate a forward extremity of the belt member for promoting attached flow ahead of and over the bag member. A pair of the belt members can connect the bag member between tandem articulated vehicle elements for smoothly covering a gap between the elements, the bag member being formed of a thin, stretchable material that assumes a pleated condition when relaxed, the pleats disappearing when the vehicle elements are proximately aligned.

Abstract: Apparatus for streamlining a tractor-trailer truckcomprises an inflatable balloon bag member at an end of the trailer. Supporting attachments for the bag automatically lock when the bag member is inflated but may be easily disconnected once the bag is deflated. The attachments are hinged for loading door clearance, a top attachment being hinged forwardly of the end for swinging the deflated bag to one side of the trailer. A belt timber reenforces the bag between the attachments, the bag being otherwise self-supporting. Both front and rear bag members cooperate to significantly reduce aerodynamic drag and fuel consumption on long hauls.