The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Signal Corps, the USAF was established as a separate branch of the United States Armed Forces in 1947 with the enactment of the National Security Act of 1947.
The ATDA (Augmented Target Docking Adapter) had been prepared as a back-up target in case of an GATV (Gemini Agena Target Vehicle) failure. The ATDA was a short cylinder consisting of a target docking adapter cone mounted on front and containing a communications system, a guidance and control system, and a reaction control system. It also had running lights, but unlike the GATV, the ATDA had no propulsive capabilities for orbit changes.