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GENERAL DYNAMICS
Convair Division

Enclosure

PLANNING FOR FUTURE SPACE PROGRAMS

General Dynamics has participated in the nation's space program since its beginnings. We are deeply interested in the plans for the future and trust that the following will help to affirm and accomplish these plans.

The next few years will provide unprecedented opportunities for the United States to use space to satisfy broad civilian and military needs. The pioneering phase of space utilization is over; the usefulness of space has been demonstrated in terms of very tangible benefits. Our activities in space have resulted in significant advancements in communications, weather forecasting, medical science, crop prediction, and mineral survey, to name but a few in the civil sector. The enormous contribution to defense needs no amplification.

The proper direction for future activities seems clear: NASA's earlier development of communications satellites has set the pattern for evolving space applications to the point where commercial investment can follow. With the advent of the Space Shuttle, we have a similar opportunity to develop a capability in space to serve an even broader spectrum of our society. With a very modest initial investment, a service center can be developed that will significantly expand the utility and economy of the Space Shuttle.

The principal guiding criteria for future space programs must center around their benefits, an economic justification, and public acceptance. Improved communications at low cost, information for better planning and forecasting of earth-based operations, disaster warnings to avert human misery, new products for use on earth, and security from man's own misadventures are clearly benefits. But there are also benefits in scientific investigations that advance the frontiers of knowledge. They too have a place in the space programs of the future. For example, we need to know more about the sun and how it affects the earth's environment. The ability to forecast cyclical climatological behavior is of enormous social and economic significance. Lunar and planetary explorations provide basic scientific data fundamental to the advancement of knowledge and help satisfy our cultural imperative to explore and understand the unknown.

GENERAL DYNAMICS

Convair Division

Page Two

The Space Transportation System is the keystone of our future role in space. It marks the beginnings of routine operations and a period of rapid growth of services and benefits in many directions. It promises an era of greater international cooperation as experience demonstrates the advantages of the system. It is the avenue to accelerated commercialization of space, if future development efforts are planned along lines that invite the investment of private capital.

During early flights, the Shuttle/Orbiter will serve two roles. For some missions it will provide transportation to low earth orbit, from whence payloads will be deployed to their orbits of operation. For other missions, such as Spacelab, it will provide an operations base where experiments can be performed under the control of crew members for as long as the Orbiter is able to provide the necessary services and support. It is in this mode that we see the opportunity to expand space services to provide more benefits to mankind. Development of standard payloads, as well as having people on orbit for monitor and repair and prolonged orbital stay-times, will significantly extend our capabilities in space and allow us to implement a greater span of beneficial services.

The public must be convinced of the benefits, and they must also be convinced that our plans will ensure that their money is being spent wisely and efficiently. The key to expanding our capabilities in space and responding to the need for economic justification is to extend the routine services that a Shuttle/Orbiter will be able to provide for only a limited period of time at low power levels. Ideas for auxiliary systems to produce additional services and utilities have been introduced. With access to such services, payloads can be more efficient and can operate for prolonged periods.

Conceptually, an auxiliary system which we call a service center would replace the Orbiter as a berthing station for payloads (including Spacelab). This center would provide electrical power and heat rejection, stationkeeping and positioning, and communications. Relieved of providing these requirements independently, payloads become simpler and less expensive. Even more significantly, the cost for repetitive launching, orbiting, and return of payloads is eliminated.

GENERAL DYNAMICS
Convair Division

Page Three

Development of a service center may be the single most important and fruitful development to follow the Space Transportation System. We are aware that other countries, particularly Germany, have realized its significance and are interested in its pursuit. Its importance to this country must be emphasized, for it is a key development for much of our future space activities.

Preliminary studies show that this capability can be initiated for a low initial cost. We see a period of rational growth during which the program is simple at the beginning, grows in accord with demand, and provides orbital services under a plan that has the flexibility to meet the changing and growing needs of all space users. This approach will ensure retention of U.S. leadership in space in a framework that recognizes the necessity of adhering to a limited budget.

The attached figure, which shows a typical plan under consideration by NASA, illustrates how an evolutionary approach to a service center can be implemented. At upper left (a) is shown the simplest approach to extending Shuttle/Orbiter capabilities: providing extra power for experiments and extending orbital stay-time. This can be done with deployable solar power arrays and radiators packaged in the Orbiter cargo bay. The next extension of capability (b) is a simple, free-flying power module a "plug in" utilities center for the Orbiter for missions that require additional power and orbital stay-time. The underlying idea for the simple service center is to configure it initially for easy, logical growth along lines that closely match growing needs.

In the next phase (c), payloads can be parked in orbit while attached to the service center. This step eliminates the need for repetitive transport of payloads like Spacelab into orbit and marks the beginning of automated on-orbit operations. Manned attendance is still limited to using the Orbiter. In step (d), the service center has been augmented to provide more power and added services. Multiple payloads are berthed to it. They operate in an automated mode with periodic tending by the Orbiter for servicing, replenishment of consumables, repair, and maintenance. Data and command links are in full operation.

GENERAL DYNAMICS

Convair Division

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The service center could be expanded as shown in (e) and (f) to provide full basic utilities, plus an operations module (perhaps a modified Spacelab) to house servicing personnel. Other special-purpose modules may be required as the program progresses. These would be interconnected, serving as a centralized permanent facility in space. Eventually, with the use of orbital transfer vehicles, remote services to independent satellites can be provided. We can now fully utilize the advantages of environments not found on the earth's surface for producing a range of useful products. An orbital service center can provide industry with an early capability for proceeding with developments and demonstrations leading to industrialization of space. When this stage is reached, the Space Transportation System reverts entirely to its intended transportation role: that of a reusable transportation system. The service center fulfills a need that might otherwise call for a larger Orbiter fleet.

The importance of an orbital service center is underscored by the results of an international and domestic survey we recently initiated to determine the views of a broad spectrum of potential users regarding such a development. The results are not complete, but they show universal agreement regarding the need for orbital services such as power, replenishment of consumables, communications, and manned attendance. Some observers note that providing these orbital services is the only solution for complex experiments that will require more time to accomplish than the Shuttle/Orbiter alone can provide.

It is important to observe that the above system will be developed and deployed in an evolutionary and prudent manner, compatible with other national needs and priorities.

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