and were especially preparing for the re-entry phase. When the correct attitude was achieved, two spin rockets the base of the body were activated to impart a 60-rpm rotation to the body, and, upon attaining this rate, nose cone separation occurred. No controls were exercised on the nose cone after separation because of the high Mach re-entry speed. G&C was accomplished by an all-inertial system that was based on the principle of constraining the missile as closely as possible along a pre-calculated standard trajectory. This work was done by a null-seeking system that continuously compared actual expedience data with that which had been precalculated. Then, attempts were made to eliminate the errors by gimballing the engine and signaling the main and vernier cutoffs at the appropriate times. Total flight time for the JUPITER for a maximum range firing was 1,016.9 seconds. At the end of 70 seconds from lift-off, the missile experienced its maximum dynamic pressure (13.69 G's) during the rise, and main engine cutoff occurred at the end of 157.8 seconds at a speed of Mach 13.04. Separation of the thrust unit and the vernier start happened at 161.8 seconds, and vernier cutoff was at 173.8 seconds. Nose cone separation occurred at 339.3 seconds, and the nose cone reached its zenith at 552 seconds. Re-entry began at 950 seconds (Mach 15.45) at about 100 km's in height, and maximum dynamic pressure (44 G's) during the descent was exerted at 980 seconds. Then, impact occurred at the previously cited 1,016.9 seconds when the aerodynamic drag had reduced the speed to Mach 0.49 64 . _____________________________

64. Ibid.; See Appendix 5.