15 stage to the home launch site if the separation speed exceeds about 3000 feet per second. However, the chart is rather accurately indicative of the boundaries within which any design must be fitted. Besides facilitating the comparison of already existing proposals, the chart can be used to generate new ones. An example is shown by Figure 2.1-b. A nose cone having a mass of 79,926 lbs. is to be detached on a near-parabolic ellipse. The first stage is detached when the horizontal component of speed is 3000 feet per second, and returned to the home launch site by retrothrust. Seven tanker rockets of the same mass are launched together with the rocket which carries the spacecraft. Knowing the masses and propellant densities, it is possible to calculate the volumes, and to plot the sizes as shown. The half-angle of the cone was adjusted to be 14.03°, in order that its base diameter, and the diameter of the launch rocket, would be the same as the diameter of the SATUR V, shown for comparison. Also shown for comparison is a single-stage-to-orbit rocket taken from Figure 2.1-a. It, too, is intended to be accompanied by seven tankers. The mass of the nose cone is taken from the tables in Section 2.2, which follows. It is obvious, of course, that the eight rockets described above could be consolidated into a single large rocket. The single space rocket would have a mass of only 573,570 lbs. on a near-parabolic parking orbit, compared with an agregate of 8 x 79,926 639,408 lbs in the eight smaller rockets, only 0.897 times as great. The advantage of dividing the rocket into eight equal messes is that for the majority of missions, only one, two, or a few rockets would be required. Only for a few missions, such as manned expeditions to the near-by planets, or one-way landings of automated cargos on Ganymede or Titan, and a few others, would the full complement be required. The SATURN V can place the nose cone in a near-parabolic parking orbit, with some capability to spare. The cone can serve as a manred, earth-orbiting space vehicle, not only in low-altitude circular parking orbits, but in geosynchronous orbits, the lunar 17 libration regions, around or on the moon, and in heliocentric orbits. It is the opinion of the writer that this is possible with no increase in cost, delay, or uncertainty over the spacecraft being proposed by NASA for use on earth orbit only. The above discussion is not to be taken as a sales pitch. It is intended only to show that there is a feasible way to plan a space launch rocket. There may be better ways. Figure 2.1-a is intended to help find them. 2.2 THE SPACE ROCKET The nose cone in Figure 2.1-b is shown in greater detail in Figure 2.2-a. The sizing of the rocket, and of the stages in it, is determined as described in Section 2.4 below. The stages, together with the spacecraft atop them, make up the detachable nose cone of the launch rocket. The oxygen tanks are arranged as shown in Figure 2.2-b to double as structural elements, but mainly to reduce the thermal shielding required for the hydrogen. It is relatively easy to insulate liquid hydrogen inside a wall cooled by liquid oxygen, and it is easy to insulate liquid oxygen in space. The thrust of the motors is transmitted in tension to the bases of the oxygen tanks through hollow tension members which also serve as oxygen feed lines. It should be emphasized that the structures are identical, whether the propellant oxygen is all carried in one vehicle or in separate tankers. 2.3 THE SPACECRAFT On top of the two stages of the space rocket, in the apex of the detached nose cone, is the spacecraft proper. There are four basic, standardized types of spacecraft, described in the four subsections below. ノ These craft are to be used for such diverse duties as plasma plotters, planetary and satellite capture, landers, etc. The list is given in Section 4. Outfitting them will be a custom job for |