Documents / FOIA release
This Central Intelligence Agency file is a 1991 JPRS translation, report JPRS-USP-91-005. It carries the annotation and text of a Soviet brochure on the space program, written by one of the first cosmonauts. The brochure reviews what manned and unmanned spaceflight have achieved and calls the American lunar program a costly dead end pursued for prestige. It then proposes future tasks, including environmental monitoring satellites, orbiting factories, an international monitoring system, Mars sample return, radio telescopes and space robots.
“Low Earth orbit”15 pages
Read from the scan by GLM-OCR; expect the odd misread word.
# Concatenated JPRS Reports, 1991 Document 5 of 10 221. acceleration from a low, near-Earth orbit to a high, injection orbit (beyond the Earth's radiation belts), during which the spacecraft, without a crew, would take two or three months to move through the radiation belts (which is due to the low thrust capability of spacecraft with electric engines) 222. launch of the crew to the high, injection orbit by means of a special transport vehicle, rendezvous with the Mars mission orbiter, docking, transfer of the crew to the orbiter, separation of the transport vehicle 223. further acceleration of the orbiter to a trans-Mars trajectory with its electric engines 224. transfer to a Mars satellite orbit with its electric engines 225. waiting in orbit the return of the mission module 226. injection from Mars satellite orbit into a trans-Earth trajectory 227. direct descent of the mission crew to Earth and injection of the orbiter without the crew into a near-Earth orbit, again with the electric engines. 228. That profile involves large expenditures of energy, since with acceleration and braking during exit from planetary satellite orbit or insertion into satellite orbit at low thrust, the velocity characterizing the energy expenditure almost doubles. That is why if the use of typical chemical-fuel rocket engines with a thrust capability of around unity yields a total characteristic velocity of 4.5-7.3 km/s (including the energy spent for exit from Earth satellite orbit), then the use of electric engines produces a velocity of 9-14 km/s (depending on how good the injection dates are and what the Mars satellite orbit parameters are). In and of itself, that's not strange at all: the high velocity of the exhaust jet compensates for that drawback. Electric engines can produce an exhaust velocity of around 50,000-100,000 m/s instead of the 4600 m/s of even liquid-fuel oxygen-hydrogen engines. That is why the fuel needed for those operations is 9-24 percent of departure mass in Earth satellite orbit for a spacecraft with electric engines, but 63-80 percent for a complex with liquid-fuel rocket stages. In that context, one can see the very important advantage of electric engines: an increase in the final mass of the spacecraft (or in the mass of the Mars mission module) has little effect on an increase in the departure mass or, consequently, on the overall complexity of the undertaking in the process of its development and creation.
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FOIA release, from the cia-readingroom collection. The PDF is mirrored here; the original link is above. The text was read from the page images by GLM-OCR; expect the odd misread word. 53 pages are in the text index: search them above, or from the library's search.