officially announced the transfer of the Army's Development Operations Division to NASA. Saturn emerges The Saturn C vehicles imagined in the Silverstein Committee report were never built. As soon as the Saturn became a NASA-tuned design of high performance, the DoD became less interested in it for their own needs. Development of the Titan continued for these roles, and as a result the flexibility offered by the variety of Saturn C-model intermediate stages simply wasn't needed, and were eventually abandoned. All that survived of the recommendation was the S-I first stage and the smallest of the new upper stages, the S-IV. It was originally intended that the S-IV would be equipped with four upgraded Centaur engines, but to decrease risk it was decided to use the existing engines and increase their number from four to six. A new, larger engine, the J-2, was already in the pipeline that could replace these. The original S-IV design, the 220 inch with six engines, was used only for a short period until a larger diameter 260 inch version was created for the Saturn Block II models, and then finally replaced with the J-2 powered S-IVB of the Saturn IB. Notes 1.The full text of the request can be found in the Appendix of the Semiannual Technical Summary Report on ARPA Orders 14-59 and 47-59. 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. References Report on Saturn, pp. 4, 7, 8, and table III. Emme, "Historical Perspectives," p. 18; Robert L. Rosholt, An Administrative History Reports of the United States government NASA oversight