The Atlas SLV-3 was a stage and a half rocket, built as a standardised replacement for earlier Atlas launch systems, which had been derived from the various Atlas missiles. A Burner upper stage was flown on the final flight to increase payload.
ATDA in orbit, with its payload fairing still attached.
It is most well known for launching the Augmented Target Docking Adapter (ATDA), a backup for the Agena Target Vehicle which was to be used by Gemini 9 after its GATV failed to reach orbit. The launch was conducted on 1 June 1966, and was the first flight of the Atlas SLV-3 as an independent vehicle. The rocket lifted the ATDA to a nearly perfect 185-mile (298 km) orbit, yet telemetry indicated the payload fairing had only partially opened and failed to separate. After rendezvous with the ATDA, the Gemini 9A crew confirmed the condition of the fairing, which prevented them from docking.