It was used as the upper stage, and provided improved performance. On 13 April 1960, a Thor-Ablestar launched Transit 1B, the first experimental satellite of what eventually became the Global Navigation Satellite System. On 22 June 1960, a Thor-Ablestar launched the first Galactic Radiation and Background (GRAB) electronic intelligence (ELINT) satellite for the United States Navy.
It acted as the upper stage, enhancing performance. On April 13, 1960, a Thor-Ablestar launched Transit 1B, which would eventually become part of the Global Navigation Satellite System. On June 22, 1960, a Thor-Ablestar deployed the first Galactic Radiation and Background (GRAB) electronic intelligence (ELINT) satellite for the United States Navy.