Saturn B-1

Studied in 1959, the Saturn B-1, was a four-stage concept rocket similar to the Jupiter-C, and consisted of a Saturn IB first stage, a cluster of four Titan I first stages used for a second stage, a S-IV third stage and a Centaur high-energy liquid-fueled fourth stage. Like its proposed predecessors, the Saturn B-1 never flew and neither did the Titan cluster stage. The S-IV however flew on the Saturn I.