INIS-jnf—8969 BUDAPLCi <*» CONGRESS OF THE INTERNATIONAL ASTRONAUTICAL FEDERATION BUDAPEST HUNGARY 10-15 OCTOBER 1983 m m XXXIV CONGRESS OF THE INTERNATIONAL ASTRONAUTICAL FEDERATION ABSTRACTS OF PAPERS BUDAPEST, HUMGABr Oct. 10-15, FOREWORD Abstracts included in this book art ordered according to the IAF nuuber assigned to each paper eooepted for presentation at XZZI? IAP Congress. Experience hae shown that the chosen arrangement is the nost conrenient one and allows the easiest access to the abstraots. The IA? paper nuBber can be found in the Final Programe of the Congress under: - the Technical Session,wbere the paper is presented - the author's name, listed at the end of the Programe. The Abstracts of the Student Conference and of Space Law Colloquium are at the end of this book. Abstracts of papers arriTed later than August 1st are not included in thie collection. ftingarian Astronautieal Society - 2 - IAr-83~O1 EXOSAT/DELTA - DEMONSTRATED SHORT-TERM BACKUP LAUIfCHER CAPABILITY THROUGH INTERNATIONAL COOPERATION by J. K. Oanoung, Manager, Spacecraft Integration, Delta Program McDonnell Douglas Astronautics Company G. Altnann, EXOSAT Project Manager, European Space Agency P. Eaton, Chief, Expendable Launch Vehicle Programs National Aeronautics and Space Administration J. D. Kraft, Delta Mission Analysis and Integration Manager, National Aeronautics and Space Administration ABSTRACT An important exploration of eosnie x-ray sources currently under wey Wan made possible by a unique example of international cooperation. The EXOSAT spacecraft, designed, developed, qualified, and prepared for launch by the European Space Agency (ESA), was successfully launched by the National Aeronautics and Space Administration (NASA) Delta launch vehicle in May 1983* EXOSAT was originally scheduled for launch on the European Ariane rocket, but due to unforeseen schedule realignments, ESA, in cooperation with NASA, selected the Delta for this mission in February 1983. The unique feature of this endeavor was the extremely short "lead time1* required to integrate the spacecraft and launch vehicle. This integration task, normally requiring 18 months of prelaunch preparation, had to be completed in only 3 months. Within this compressed schedule, the EXOSAT and Delta Projects had to complete not only the standard launch preparation activity (trajectory designs hardware drawings and analyses, operations planning, network support analyses, and hardware procurement and assembly), but a number of miasion-peculiar drawings and analyses (yo-yo despin and separation system designs, special experiment cleanliness requirements, special range safety analyses, and TM data link configuration requirements). Essential to the successful accomplishment of this seemingly Impossible task was the spirit of "International cooperation In space" - the theme of this year's IAP Congress. This paper desoribes (1) brief histories of the EXOSAT and Delta Programs, (2) the circumstances leading to this unusual integration activity, (3) the management and technical approaches for solving the sohedule compression problem, (1) the launch vehicle •edifications accomplished to satisfy the apaoeoraft requirements, and (5) a sunaary of those elements of the EXOSAT/Delta learning experience which could contribute to the achievement of continuing short-term backup launch capability. Several important conclusions are underscored by the EXOS&T/Delte experience. In forthcoming periods of high Icunoh rates and •ultiple payloads, there is a need for flexible scheduling in order to avoid oostly launch delays. This required flexibility can be aohieved by the short-tern osllup capability demonstrated by the EXOSAT/Delta mission, provided that a backup program is established and the neoessary management planning is implemented. _ 4. mm IAF-83-02 THE NEED FOR ADDITIONAL SPACE SHUTTLE 0R8ITERS J. Jeffrey Irons Minority Technical Consultant Committee on Science and Technology Rayburn House Office Building - 2321 Washington, D.C. 20515 USA Throughout recent fiscal year National Aeronautics and Space Administra- tion (NASA) authorization hearings, a number of witnesses have testified that the planned four Space Shuttle orblter fleet wilt be unable to adequately serve the projected space traffic requirements by the late 1980s. On June 15. 1982, the Subcommittee on Space Science and Applications held a hearing to examine the Issues associated with the need for Increasing the size of the orblter fleet. The Subcommittee on Space Science and Applications, one of seven subcom- mittees of the Committee on Science and Technology, has annual authorization of appropriations for NASA. A major portion of the civilian space agency's budget ts spent annually on developing the reusable Space Transportation System. As the system begins Its transition from developmental to operation- al status, a number of issues have emerged that require review by the Subcom- mittee. One of the most important and overriding issues is the need for additional orblters for the Space Transportation fleet. This paper deals spe- cifically with that Issue. A second, related objective of the hearing was to examine a concept which has been proposed by the Space Transportation Company, Inc. (SpaceTran) where- by the procurement of the fifth orbiter vehicle would be financed through In- vestments from the private sector. SpaceTran was formed in 1979 with the ex- press purpose of determining whether the private ownership and operation of a fifth Space Shuttle orbiter would be economically feasible. SpaceTran has re- ceived partial financial backing and support from the Prudential Insurance Company of America. In February 1982, SpaceTran submitted a proposal to NASA to procure an orbiter in exchange for exclusive marketing rights of foreign and commercial payloads aboard this vehicle. SpaceTran subsequently sent NASA a revised proposal In Hay 1982. To date, NASA has not evaluated the SpaceTran proposal. The Subcommittee attempted to examine fully the issues associated with the need for additional Space Shuttle orblters. Witnesses from within NASA, the American Institute of Aeronautics and Astronautics, Boeing Aerospace Company, SpaceTran, and Prudential Insurance testified on the requirements for a fifth or additional orblters; the feasibility and timing of the SpaceTran proposal; military and civilian launch requirements through the late 1980s; and the ability of the reusable Space Transportation System to adequately support both civil and national security missions. This paper addresses the previously mentioned Issues In detail, and sup- ports the discussions with excerpts of testimony and witness answers to written Subcommittee questions. - 6 - IAF 83 04 DEVELOPMENT OF THE THRUST AUGMENTED VIKING ENGINE AND F1RSI STAGE DRAKKAR PROPULSION SYSTEMS FOR THE ARIANE 3 LAUNCHER. A. SOUCHIER, J. PASQUIER SEP Space and !iquid Propulsion Division On the Ariane 3 version of the Ariane launcher, 1st and 2nd stage perfor mances have been increased by use of a thtust augmented Viking engine. Other modifications for Ariane 3 include the use of two solid propellanl boosters 700 kN thrust each, burning for 28 seconds after lift off, and improvments 1n the third stage. All these modifications boost from 1750 to 2 585 kg the launcher capacity In geostationnary transfert orbit.The program was decided at the beginning of 1980. First flight 1s scheduled for March 1984. SEP 1s the prime contractor for the studies and tests of the Ariane 3 first and second stages propulsion sy&tems (1e all the hydraulic and pneumatic systems Including the Viking engine). The Viking thrust augmentation have beengobta1ned by chamber pressure augmentation from 54,5 10 Pa to 58,5 10 Pa. The pressure augmentation Increases the combustion Instabilities risks. Thus after the 10? launch failure following combustion instabilities in the Viking chamber It ap- peared that the thrust augmentation would be more difficult than planned. The Injector modifications developed after L02 flight were introduced on the Ariane 3 Viking but 1t was also necessary to change the fuel from pure UDMH to a mixture of UDMH an 25 % of hydrazine hydrate. First test with this new fuel occured in April 1901. With these two modifications Viking engines were able to operate satisfactorily at 65 10' Pa chamber pressure. During the ARiane 1 post L02 test program the strong effect of chamber configuration on combustion stability was discovered so it was decided to increase the stability margins by a chamber mortification on Ariane 3 : a circular gap at the upper junction between the composite throat and the chamber has been introduced to shift the chamber mecani- cal frequencies. This modification divides by a factor of three the cri tical combustion vibration level. A first chamber with such a modifica- tion was tested with succes 1n November 1981, since then other tests were conducted with success and decision to apply this chamber modifica- tion for Ariane 3 was taken in May 1982. Following all these stability improvmersts the first injector acceptance tests in December 1982 and January 1983 for ARiane 3 first flight ended with a 100 X success. For the first stage Drakkar propulsion system development, multiple lesis have been planned on the same propulsion bay with four engines on the PF 20 test stand at SEP Vernon. The propellents are fed to the bay in a configuration quite similar to the first stage flight tanks configura- tion. Thanks capacity reaches 220 tons as for the Ariane 4 launcher. Thus the tests