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Show SALTFLAT JNEfirSnFEpRlJAgylgM far exceeds the cost of launch operations. One of the most powerful arguments for the shuttle is the great promise it offers for substantially reducing the cost of payloads. A concept of a shuttle era satellite is illustrated on the atThe tached Figure MH70-706dimensions of the shuttle payload compartment will permit relaxed dimensional and weight constraints for the majority of the payloads carried. Use of standardized system units will offer superior performance at lower cost. These units can also be made replaceable in orbit. The ability of the shuttle to return payloads from orbit to earth will permit reuse of satellites either in total or in part, and may make economically attractive the use of high cost but extremely long-live- d subsystems such as radioisotope thermo-electri- c generators since the initial cost of such an investment can be amortized over the operating life of several satellites. An excellent example of the utility of the Space Shuttle is how it could have influenced the Orbi-ta- l modes of flight opportunities made possible with the shuttle due to thelarge capacity of the shuttle compartment, the revisit capability of the shuttle, and the capability of the shuttle to return the payload to earth. Because low launch and reentry acceleration levels (not to exceed 3G), persons not trained as astronauts who are in good physical condition can be expected to carry out missions aboard the shuttle, The depicted Space Shuttle operational modes will be utilized to support the individual mission requirements of a wide spectrum of payloads: science (near earth and planetary), earth observation, communication, navigation and Department -- 2. Astronomical Observatory Program in which three Orbital Astronomical Observatory satellites were launched. The battery charger failures on OAO I could have been corrected by returning the satellite from orbit and repairing the damaged satellite. OAO II performed beautifully, and the problems in OAO II which have occurred beyond the planned operating life could have been corrected in orbit if a shuttle had called . NASA . . has Gunn been available, and if the OAO McKay Washington, D.C. upon Representative Administrator James Fletcher to answer questions dealing with the NASA proposal for a had been designed for such maintenance. The shroud-jettiso- n space shuttle system. Following are the questions and Fletcher's answers. . problem that prevented the third OAO from attaining orbit in To evaluate any. pro- tween manned, and automated in McKay Figure November, 1970, could have posals for a Space Shuttle we programs. The shuttle satisfies MT71-5183As a reusable space trans- been avoided if the shuttle had must examine the goals for the the many transportation requirebeen the launch vehide. system. My first question, then, is ments aimed at exploiting earth porter, the shuttle will replace the The potential of the Shuttle y why do we need a Space Shuttle resources and earth orbital appli- entire launch vehide stable cur- for redudng costs in the space cations. It will be utilized for rently in the national inventory System? program, therefore, involves both placement and retrieval of auto- with the exception of the Scout Fletcher As I indicated in my mated satellites, short term sortie and the Saturn V. This is illus- transportation costs and payload costs. The attached Figure cover letter, the primary need to missions, and for space station trated by the shaded area on the MT7 illustrates thevarious obtain the benefits of continued logistic support. Flight accelera- attached Figure MH70-751j cost is for a low space activity tions will be kept low so that Because the shuttle is reusable, operational space transportation scientists and engi- its cost per flight is independent system. It is the key to the space neers can be transported on sortie of the payload carried; and this is program, the single development investigation missions. onq of the very attractive advanwhich is essential to the future ex-- , The one way we can continue tages of the shuttle over expendaploitation of the space environ- a nationally viable and economi- ble boosters. The points on the ment. The cornerstone of this cally effective space program in attached chart, MH71-568new approach to space flight is the future is to develpp the reusashow the minimum cost today for the Space Shuttle, a cost effecble Space Shuttle to drastically launching a payload of a given and reliable versatile tive, reduce the cost of space flight capacity; for example, the cheaphighly system of transportation between operations and provide the re- est way to place 28,000 pounds the surface of the earth and earth quired payload versatility. into earth orbit is to use a Titan orbit. III C launch vehicle at a cost of What do we expect The shuttle must accomplish McKay over $20 million. Our studies so the goal of drastically reducing from such a system? far show that we can operate the the cost of space transportation, j (a) What payloads may we ex shuttle for less than $5 million It can do this by providing a repect the Space Shuttle to put per flight. The shuttle can perusable system with a high launch into orbit? form the task of pladng into orbit rate capability and short turnany payloads ranging from the around time. It must possess a (b) How often will this shuttle be size of those normally lofted by used (launch rate)? ; . large and highly flexible payload the Thor Delta to a size exceeding capability designed to support a Fletcher The shuttle will per- those that can be launched by a wide range of scientific, defense, form the function of trans- Saturn IB. In addition, the fact commercial and international porting, to and from low earth that several smaller payloads such uses. In addition to the transpororbit, a variety of payloads. Since as those in the Scout and Thor tation savings, very significant a large number of the payloads en- Delta Class can be carried at the economies will be realized in the visioned for the period of shuttle same time ' is another way in ..payload area due to relaxed operations must be placed in a which the Space Shuttle can re--' weight and volume constraints, j number of synchronous orbits, or duce the cost of space operations. capability to revisit and return i require escape velocity for a plan- The payload compartment need payloads, and safe intact abort of j etary mission, the shuttle will be not be full for the shuttle to be payloads. The shuttle will there-- designed to accommodate a high economical, since any class pay-loa- d fore supply the sound, flexible,. ; energy stage sometimes referred now carried by the Thor and economical base necessary to as a Space Tug. After the shut- Delta or, larger vehicle can be ", for our future space activities. tle has achieved low earth orbit carried economically after the on based the Our planned program Space Tug and its payload is shuttle system is operational. . com-The cost of the launch operachecked out, released from the the concepts of reusability, and the shuttle airline and operations, however, is only part of the Tug orbiter, Space type monality, is to the to a allow also will tions ignited propel story in reducing the costs of payload space proits' space operations. The cost of pay-loarequired orbit or escape gram for science and applications illustrated is be This distinction the eliminates (spacecraft and' satellites) .that operation Congressman r.lcKay Questions NASA Admistrator James Fletcher about the Space Shuttle (D-Uta- h) the-attache- A. 45 I 1. non-astrona- . of Defense. The attached Figure illustrates the foreseen launch rate frequency envisioned for the shuttle. The number of flights for various calendar years associated with the space program in the United States and in the USSR is depicted in the shaded area. The largest peak of activity in the United States occurred in 1966. At the present time, the number of flights per year is less than 40. The historical portion of the diagram indudes all U. S. Flights MH71-568- 0 that is, other commercial, and scientific groups. ut 1, ms9 ! I ; -- . . ; -- vel-pcit- y. ds U. S. agencies, NASA, DOD, and a small number of European satellites launched by the U. S. For the United States, a buildup is envisioned in space activity as the shuttle becomes operational in 1979 and as experience shows its utility. Although economic studies indicate the shuttle to be an excellent investment even on the basis of the current low U. S. launch rate less than 40 flights per year it is expected that the dramatic reductions in payload costs vided by using a reusable shuttle and the new opportunities afforded by retrieval and return to earth for reuse will attract a large number of users from national and international governmental, (Continued Next Issue) " |