Saturn Development Plan
 The report of the Saturn Vehicle Team on 15 December 1959 gave lunar and deep space missions (4500 kg payload) first importance; "stationary" 24-hour equatorial orbit missions second priority; and manned spacecraft missions in low earth orbit (e.g., Dynasoar) third. Five recommendations were made regarding launch vehicles for these missions. A plan was needed for the orderly development of a series of vehicles of increasing payload capability, with emphasis on reliability. All upper stages would use liquid hydrogen-oxygen. The first of the vehicle series should be configuration C-1 (table 13). Fourth, development of a new hydrogen-oxygen rocket engine with a thrust of 668-890 kilonewtons (150 000-200 000 lb) should begin immediately, along with design studies of stages using it. Finally, a funding plan as prepared by ABMA for vehicle development was recommended.32
Of six vehicle configurations considered, only three were recommended (those with "C" designations, table 13). Combinations of only three hydrogen-oxygen upper stages would serve for all three vehicles in a "building block" approach proposed by Hall (figs. 56, 57).33 The two engines proposed for these upper stages were the Pratt & Whitney RL-10, part of the legacy of the Suntan project, and a new and larger engine which later became the J-2.
The Saturn Vehicle Team presented the results in a meeting with T. Keith Glennan, NASA administrator; Hugh L. Dryden, deputy administrator; and Richard Horner, associate administrator; and its recommendations were approved. On 29 December, Horner discharged the vehicle team and replaced it with a new Saturn committee that he and Herbert York had agreed would be useful in technical guidance for Saturn during the interim period, before ABMA and the Saturn were formally transferred to NASA the following March.34 By this time, NASA had split its space effort into two parts with Silverstein heading the office of spaceflight programs, concerned chiefly with
 During the next two years, Saturn configurations were restudied as part of the national commitment in 1961 for a manned lunar landing, but one basic concept established by Silverstein did not change: the use of hydrogen in all Saturn upper stages. The work of Silverstein, Hall, and the other members of the Saturn Vehicle Team in taking a bold stand in choosing to use liquid hydrogen for Saturn was one of the major decisions that made the great manned spaceflight events of the 1960s and 1970s possible.