Abstract: An air inflated bag of flexible sheet material includes a front portion which is mounted on the body or cab of a vehicle such as a tractor hitched to a semi-trailer. A rear portion of the inflated bag extends between the cab and the trailer body to provide for a smooth non-turbulentflow of air around the cab and to the side and top walls of the trailer body for significantly reducing the aerodynamic drag on the tractor-trailer vehicle. The front portion of the bag is provided with a generally horizontal inlet which is located directly above the front windshield of the cab to direct a portion of the upward flow of air over the cab into the bag and thereby effect dynamic inflation of the bag at a predetermined road speed. The bag may be collapsed to a folded condition adjacent the cab for when the tractor is being driven without a trailer, and a bottom recess is formed within the rear portion of the bag to provide for extending service lines between the cab and the trailer.

Abstract: An air inflated bag of inflexible sheet material includes a front portion which is mounted on the body or cab of a vehicle such as a tractor hitched to a semi-trailer. A rear portion of the inflated bag extends between the cab and the trailer body to provide for a smooth non-turbulent flow of air around the cab and to the side and top walls of the trailer body for significantly reducing the aerodynamic drag on the tractor-trailer vehicle. The front portion of the bag is provided with a generally horizontal inlet which is located directly above the front windshield of the cab to direct a portion of the upward flow of air over the cab into the bag and thereby effect dynamic inflation of the bag at a predetermined road speed. The bag may be collapsed to a folded condition adjacent the cab for when the tractor is being driven without a trailer, and a bottom recess is formed within the rear portion of the bag to provide for extending service lines between the cab and the trailer.