According to a 1959 report on Saturn development, the vehicle A-1 configuration, which has a modified Titan stage 1 and a Centaur upper stage as upper stages, was considered due to have early flight availability and low costs. How, it fails to meet the mission requirements for lunar and 24 hour missions.
A 1959 report on Saturn development indicated that the A-1 configuration, which incorporated a modified Titan stage 1 and a Centaur upper stage as upper stages, was initially considered viable due to its anticipated early flight readiness and lower costs. Nevertheless, it failed to fulfill the mission requirements for lunar and extended-duration missions.