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This Defense Intelligence Reference Document, prepared by the Defense Intelligence Agency and dated 8 March 2010, was produced under the Advanced Aerospace Weapon System Applications (AAWSA) Program. It gives a historical and technical review of how to reach space and return. It covers hypersonic gliders, air-breathing and rocket propulsion, thermodynamics and materials, and launch options. It argues that reliable, schedulable access to low Earth orbit is mainly a hardware and propulsion problem rather than a technology one.
“Edwards Air Force Base”1 page
UNCLASSIFIED/ ,erg A gffllil.t.L '1181!!! 8HLY Figure 39 shows the deviation from the 1962 standard atmosphere for a hypersonic glider entering the atmosphere from the central South Pacific (summer) to northeastern Russia (winter). The deviations from constant-density shells based on the 1962 standard atmosphere are significant. With today's computers, not ignoring the actual atmosphere is only a bookkeeping task. Hypersonic glide ranges at near maximum L/D ratio are to be generated. The local density is critically important, as it is determined by the lift coefficient for L/D maximum. q = • plan g I - V = I 188.5 _y__ gcrW /S [ ( )'] ~ )' ( CL)max LID 25,535 1000 (5) The seasonal variations are enough that the glider should have the correct density and temperature distribution in its flight-control computer so that unexpected alterations in the flight trajectory are not mandated during entry. The atmosphere is analogous to a constant-energy system-if the lower altitudes are hotter, the upper altitudes are colder, and vice versa. In terms of deviations from the standard, the coldest upper-altitude temperatures most likely encountered are at 50,000 feet over Saudi Arabia in summer, and the warmest atmospheric temperatures are at 27,000 feet over Russia in winter. -48% • 1962 Standard Atmosphere 1966 Standard Atmosphere Supplement 1959 Selected Meridional Cross sections of the Northern Hemisphere NAVAIR-50-1C-59 -19% • +7% • Figure 39. Earth's Atmosphere. Earth's atmosphere is not a series of concentric, constant-density shells or globally uniform, and flying from one hemisphere to another entails significant dev1at1ons from standard def1nit1ons. 36 UNCLASSIFIED//F&A 8FFIIIAL '1181! &••tY
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Report, from the dia collection. The PDF is mirrored here; the original link is above. 56 pages are in the text index: search them above, or from the library's search.