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It will be surprising to many to discover that today's airplanes and space vehicles have a lot in common. Both have engines using fuels and oxidizers to defy Earth's gravity. Some space vehicles, such as the Space Shuttle, have wings to return to Earth like an airplane. Airports and spaceports, too, share a number of features. Both have hangars, service shops, control centers, even runways. A major difference between the two is flight rate. The process of readying a modern-day space vehicle is costly and time-consuming, primarily due to the complexity of the vehicles and ground operations required to prepare them for flight. One way to achieve higher flight rate and lower payload delivery cost is to create new, cost-effective space transportation that addresses both flight and ground systems in one unified design. This approach is aimed at providing a major reduction of vehicle-to-ground interdependence. Enter Vision Spaceport, the first joint-sponsored research agreement between NASA Kennedy Space Center (KSC), industry, and academia. Each member of the partnership lends invaluable expertise to stimulate the creation of integrated space vehicles and spaceports. Kennedy Space Center, as the Center of Excellence for Launch & Payload Processing Systems, in its role as the US Spaceport Technology Center, provides a gathering place for many of those people with expertise in launch site operations. That expertise is being shared by the Vision Spaceport partnership in casting a sharp eye on developing the technologies needed to support the increased flight rates envisioned for tomorrow's spaceports.
Prominent technology needs impact both flight vehicles and ground systems. Inflight systems, reusable cryogenic tanks, simplified turbomachinery and engines, tighter integration of sub-systems, and robust thermal protection systems are envisioned as areas for intense research and development. These items, though vehicle associated, are known to contribute to operations work load, and impact both cost and cycle time (launch rate). In ground systems, a lean, integrated infrastructure is required everywhere, from propellant servicing, to command, control, and monitoring of spaceport activities. Efficient spaceport infrastructures envisioned for the future can encourage the growth of space transportation as an industry, while antiquated systems present numerous barriers to establishing record launch-rate capabilities. As new flight systems and technologies come on-line, their maturity and reliability will increase hand-in-hand, enabling still further growth of spaceport operations as hubs of economic activity. One of the greatest challenges is to encourage designers of flight vehicle concepts -- and the responding spaceport systems operators -- to develop their designs together in a synergistic manner. Neither, alone, can develop the most operationally effective systems. Economic and Policy Challenges The task of developing fully functional spaceports for the next generation of launch vehicles also has technical, economic, and policy challenges. Technology challenges include integrating a host of 21st-century systems, from operators, through electronic networks, to end items such as sensors and valves. Economic challenges include how to bootstrap financing the development of such systems, especially in the near term, while contemporary flight rates are not likely to quickly amortize such investments. Policy challenges include questions such as who will pay for such investments. Are user fees on a pay-as-you-go approach -- such as with airports -- useful guides for spaceport developments? What are the roles of private industry, and which befall government? Integrated ground and flight systems, when developed, will lead to a global proliferation of spaceports. In the near term, because space vehicle reliabilities are not yet aircraft-like, public safety will drive developers to the national ranges as mandated spaceports. Even though proposed single-stage-to-orbit systems have no components to drop en route to orbit, the single stage requires maturity and reliability far beyond current systems before flights over populated areas are envisioned. When these hurdles are cleared, the "spaceport as airport" will become a reality, perhaps seeing space planes departing from a host of new terminals. States such as Alaska, California, Florida, New Mexico, and Virginia already are investing resources to be ready and able to meet these challenges.
Routine Space Flight: Payload Cost Economic studies have indicated that cost reductions of two orders of magnitude from today's markets are required before fully elastic markets develop in space transportation. This means getting "cost" down to about $100 per delivered payload pound, with "price" perhaps only twice as high. For comparison, this means getting the cost of a trip down to about that of a round-the-world ticket (with amenities) on the Concorde. Studies show that small, efficient space fleets of about 14 vehicles, with high utilization factors (launch rate), conceivably may enable such ventures as public space transportation, or large-scale energy enterprises such as the construction of Space Solar Power energy transmission stations in the sky. Fascinating challenges await the space transport industry. Many difficult questions must be examined and answered. To lift the project off the ground, Kennedy Space Center gathered a circle of industry and academia partners to examine launch site operations and their cost-driving factors. Their goal is to identify technologies that will support the effective, affordable space transportation essential to opening space for commercial enterprise. The partners have formed a consortium of launch site analysts and engineers, known as the Spaceport Synergy Team. The members are:
The KSC partnership also is working closely with Marshall Space Flight Center, Johnson Space Center, Langley Research Center, and industry partner vehicle designers to assure the model provides the best available operational assessment for future vehicle concepts.
Together, they are developing a cost and performance modeling tool for integrated vehicle and spaceport concepts. This innovative, computer based model, when complete, will use information from the world's launch systems to estimate the cost and throughput performance of near-future designs. The model thereby can be used to assist designers of future Space Transportation Systems in focusing on achieving affordable operating cost. The prototype "core" model has been completed and currently is undergoing extensive validation and calibration using historical data in cooperation with the other NASA centers. A validated Version 1.0 beta model is expected to be available for use late this year. Based on the launch vehicle designer's input, the model is being developed to provide system design information in various categories, including, but not limited to, estimates of:
The second major functional area is Optional Facilities, including accommodation for:
The third functional area addressed by the model is Support Infrastructure Facilities, such as:
The model, serving as a decision-supporting tool, will enable designers to assess the new launch system concept and evaluate its cost-effectiveness.
The first step in using the model is to access the data input tabs. This is where designers define their flight system. Essential characteristics of the vehicle are input, as well as cargo-carrying capabilities, identity of subsystems, and other pertinent data. This step is key because vehicle characteristics influence the spaceport architecture, contributing to overall cost of the system and the resulting flight rate. After flight vehicle design data are input, the model will generate simple data sheets showing required spaceport facilities, vehicle and spaceport operational costs, processing cycle times, and numerous other cost-affecting parameters. In a simple tabular format, the designer easily can see how different vehicle designs impact launch site infrastructure, and the associated costs and cycle times. Graphical Output: The Virtual Spaceport Another more intuitive output of the model will be a "virtual spaceport" -- a real-time, three-dimensional sample rendering of facilities required by the system concept. The Virtual Spaceport uses three-dimensional launch site infrastructure models positioned on a two-dimensional ground reference. This will make the output data easier to interpret, and thus accessible to a broader audience. Some launch site facilities commonly associated with present-day spaceports may not be essential for future concepts. For instance, a horizontal takeoff space-vehicle may not require vertical processing infrastructure. Other types of spacecraft might rely on a magnetic-levitation rail for takeoff. An airport-style control tower might be used in place of a bunker-like launch control center. The artist's concept in Figure 4 shows how future-generation processing and launch control equipment dramatically may reduce the required work force and accommodate increased flight rates. The three-dimensional Virtual Spaceport will allow the user to fly through the model and examine the infrastructure from different perspectives. Many areas of the 3D model are being hyperlinked to data sheets for the particular facility in question. Kennedy Space Center, through its goal to become a Spaceport Technology Center, is a leading developer of spaceport technologies. The tools being developed there will provide an insight into spaceport designs of the future. As KSC moves into the future with greater emphasis on research and development, it is strengthening plans to be both a provider of spaceport technology, and a spaceport-of-choice for many customers of the future. As the payload delivery and operations costs continue to go down, more and more commercial cargo will be launched into Earth orbit and beyond. NASA's vision is of a day when human space flight becomes routine and affordable for anyone. The new technologies to support this vision already are being developed. Vision Spaceport is about our future. The Vision Spaceport partnership welcomes participation of organizations with a vision for achieving affordable space access. The partnership particularly seeks collaboration and expertise in key areas such as space operations performance benchmarking, technology roadmapping, cost modeling, facility visualization, and related fields. Spaceport operators also are particularly welcome to contribute their unique perspective on reducing spaceport operations costs. Potential participants should recognize that they are expected to contribute funding or in-kind resources to the partnership. All products become property of the Vision Spaceport Project and are available publicly to all interested organizations within limitations of applicable export control regulations. Those interested further may contact Carey McCleskey, Government Co-chair; e-mail: carey.mccleskey-1@kmail.ksc.nasa.gov, or Ray Byrd, Industry Co-chair; e-mail: byrdr@pgocM5.ksc.nasa.gov. For further information, visit the Vision Spaceport Web site at: www.visionspaceport.org. A 10-minute video describing the Project and the modeling effort is available to qualified space industry applicants. This article was written by Raymond J. Byrd, Industry Co-Chair, Vision Spaceport Project, and was co-written by Sergei Kossenko, Dynacs Digital Media Lab, Kennedy Space Center. Byrd has worked at Kennedy Space Center most of the past 34 years since becoming an S-1C mechanical systems engineer on the Saturn-Apollo program in 1965. His longtime experience in launch site activities is representative of the people and expertise now gathered in the Spaceport Synergy Team, with the goal of stimulating development of affordable space transportation. Sergei Kossenko is an award-winning producer of digital media products at the Kennedy Space Center. Artwork is by Pat Rawlings, SAIC Houston, Copyright 1999 Vision Spaceport Project.
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