The actual flight testing in support of JUPITER development was divided into three phases. Two of these used the REDSTONE as the flight test vehicle to prove out JUPITER components. Designated as JUPITER A's, 25 missiles were fired between September 1955 and June 1958*. Objectives of these tests were to obtain design criteria, apply the angle-of-attack meter to the IRBM, evolve separation procedures, prove guidance system accuracy, and design and prove propulsion system thrust control. To solve the re-entry problem, three missiles designated as JUPITER C's were flown. As to the tally, 20 of the 25 JUPITER A's were rated as mission achieved, two registered partial successes, and three were considered to be unsuccessful. All three of the JUPITER C's performed well. On the second firing, an attempt was made to recover the nose cone, and this failed. However, on the third and last re-entry test, the nose cone was recovered. Success was such that it was no longer necessary to continue this phase of the program, as one of the tests had ably proven the theory of long- range missile flight and the other had demonstrated that the re-entry body could be brought from space into the sensible atmosphere without disintegrating 89 . At the outset of the JUPITER program, it was planned to fire the first JUPITER-configured missile in May of 1957, but the success registered by the JUPITER A’s and C’s formed the belief that two assurance missiles could be fired before the scheduled date. As it turned out, it was well this decision was made, for JUPITER 1A had a tail-heating problem and 1B had a propellant sloshing problem. These were solved and the May firing of JUPITER 1 gave the Western World its first demonstrated IRBM. Two successive firings registered in the success box, but Missile 3A met with the previously-mentioned turbopump problem. This difficulty _____________________________

* See Appendix 7 for a chronological listing of JUPITER A firing test results. 89. Ibid.; Hist, ABMA, Jan-Jun 58, pp. 87-90; Chart, JUP Msl Plan Nr J-754, 27 Mar 61, Hist Off files. JUPITER C firing test results may be found in Appendix 8.