Moonport: A History of Apollo Launch Facilities and OperationsUpper StagesThe Silverstein Committee established two criteria for a successful Saturn program: development of a rocket with an early launch capability as well as growth potential. The group listed three missions for the initial Saturn vehicle: unmanned lunar and deep space missions with an escape payload of about 4,500 kilograms; 2,250-kilogram payloads for a 24-hour equatorial orbit; and manned spacecraft missions in low orbits, such as Dyna Soar. The committee matched a number of configurations against these missions. Current ICBMs such as the Titan were adjudged unsatisfactory; they would not generate sufficient thrust for the lunar mission. A larger, conventionally fueled second stage - 5.59-meter diameter - met mission requirements, but time and cost seemed excessive for a rocket stage with little growth potential. The solution lay with the early development of high-energy (liquid hydrogen) propellants for all stages above the first. In defense of this rather bold position the committee noted: "If these propellants are to be accepted for the difficult top-stage applications, there seems to be no valid engineering reasons for not accepting the use of high-energy propellants for the less difficult application to intermediate stages." The committee also recommended a building block concept stating that "vehicle reliability will be emphasized... through a continued use of each development stage in later vehicle configurations." The Saturn C-1* would consist of the clustered booster, a new Douglas Corporation second stage with four hydrogen burning Centaur engines of 66,720-88,960 newtons (15,000-20,000 pounds of thrust) per engine, and a modified Centaur as a third stage. The C-1 would become the C-2 upon insertion of a new oxygen-hydrogen second stage with two 667,200-889,600-newton (150,000-200,000 pounds of thrust) engines. The top two stages of the Saturn C-1 would then become stages three and four on the C-2 version. The committee proposed to launch ten C-1s starting in the fall of 1961.23 On the last day of 1959, Glennan approved the Silverstein recommendations, and Saturn got its upper stages. Chances of meeting the new schedule improved with two Eisenhower administration decisions in January 1960. The Saturn project received a DX rating, which designated a program of highest national priority. Besides reflecting the administration's support, the rating gave program managers a privileged status in securing scarce materials. More important, the administration agreed to NASA's request for additional funds. The Saturn FY 1961 budget was increased from $140 million to $230 million.24 On 15 March 1960 President Eisenhower officially announced the transfer of the Army's Development Operations Division to NASA. He took the occasion to name the Huntsville installation the Marshall Space Flight Center, for his wartime commander, General George C. Marshall. The DoD's Missile Firing Laboratory at Cape Canaveral became the Launch Operations Directorate of the new organization.
* Until 1963 Saturns were classified by a C and an arabic numeral. People generally assume that C stood for configuration; but according to Kennedy Space Center's Spaceport News (17 Jan. 1963), MSFC engineers used it to designate vehicular "concepts." Saturn C-1 denoted the concept of the S-1 booster topped with upper stages using liquid hydrogen as a propellant. C-2, C-3, and C-4 were drawing- board concepts that preceded the C-5 (Saturn V) moon rocket. For additional information on the origins of Saturn, see John L, Sloop, Liquid Hydrogen as a Propulsion Fuel, 1945-1959, NASA SP-4404, in press, chap. 12.
23. Report on Saturn, pp. 4, 7, 8, and table III.
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