Challenges of assuring crew safety in space shuttle missions with international cargoes

The top priority in America's manned space flight program is the assurance of crew and vehicle safety. This priority gained greater focus during and after the Space Shuttle return-to-flight mission (STS-26). One of the interesting challenges has been to assure crew safety and adequate protection of the Space Shuttle, as a national resource, from increasingly diverse cargoes and operations. The control of hazards associated with the deployment of complex payloads and cargoes has involved many international participants. These challenges are examined in some detail along with examples of how crew safety has evolved in the manned space program and how the international partners have addressed various scenarios involving control and mitigation of potential hazards to crew and vehicle safety.     

The International Space Station: a pathway to the future

Nearly six years after the launch of the first International Space Station element, and four years after its initial occupation, the United States and our 6 international partners have made great strides in operating this impressive Earth orbiting research facility. This past year we have done so in the face of the adversity of operating without the benefit of the Space Shuttle. In his January 14, 2004, speech announcing a new vision for America's space program, President Bush affirmed the United States' commitment to completing construction of the International Space Station by 2010. The President also stated that we would focus our future research aboard the Station on the long-term effects of space travel on human biology. This research will help enable human crews to venture through the vast voids of space for months at a time. In addition, ISS affords a unique opportunity to serve as an engineering test bed for hardware and operations critical to the exploration tasks. NASA looks forward to working with our partners on International Space Station research that will help open up new pathways for future exploration and discovery beyond low Earth orbit. This paper provides an overview of the International Space Station Program focusing on a review of the events of the past year, as well as plans for next year and the future.     

NASA's in-space technology experiments program: Status and plans

Experience with the Shuttle and free-flying satellites as technology test beds has shown the feasibility and desirability of using space assets as facilities for technology development. Thus, by the time the space station era arrives, technologists will be ready for an accessible engineering facility in space. Along with the scientific and commercial space development communities, the technology development community has been participating in defining requirements for this in-space facility. As the 21st century is approached, it is expected that many flights to the Space Station Freedom will carry one or more RT&E experiments. The experiments are likely to utilize both the pressurized volume, and the external payload attachment facilities. Based on the success of instrumenting the Shuttle itself to obtain ascent and descent aerothermodynamic data a unique, but extremely important, class of experiments will use the space station itself as an experimental vehicle.     

One hundred US EVAs: a perspective on spacewalks

In the 36 years between June 1965 and February 2001, the US human space flight program has conducted 100 spacewalks, or extravehicular activities (EVAs), as NASA officially calls them. EVA occurs when astronauts wearing spacesuits travel outside their protective spacecraft to perform tasks in the space vacuum environment. US EVA started with pioneering feasibility tests during the Gemini Program. The Apollo Program required sending astronauts to the moon and performing EVA to explore the lunar surface. EVA supported scientific mission objectives of the Skylab program, but may be best remembered for repairing launch damage to the vehicle and thus saving the program. EVA capability on Shuttle was initially planned to be a kit that could be flown at will, and was primarily intended for coping with vehicle return emergencies. The Skylab emergency and the pivotal role of EVA in salvaging that program quickly promoted Shuttle EVA to an essential element for achieving mission objectives, including retrieving satellites and developing techniques to assemble and maintain the International Space Station (ISS). Now, EVA is supporting assembly of ISS. This paper highlights development of US EVA capability within the context of the overarching mission objectives of the US human space flight program.     

Apollo: Learning from the past,for the future

This paper shares an interesting and unique case study of knowledge capture by the National Aeronautics and Space Administration (NASA), an ongoing project to recapture and make available the lessons learned from the Apollo lunar landing project so that those working on future projects do not have to “reinvent the wheel”. NASA’s new Constellation program, the successor to the Space Shuttle program, proposes a return to the Moon using a new generation of vehicles. The Orion Crew Vehicle and the Altair Lunar Lander will use hardware, practices, and techniques descended and derived from Apollo, Shuttle, and the International Space Station. However, the new generation of engineers and managers who will be working with Orion and Altair are largely from the decades following Apollo, and are likely not well aware of what was developed in the 1960s. In 2006, a project at NASA’s Johnson Space Center was started to find pertinent Apollo-era documentation and gather it, format it, and present it using modern tools for today’s engineers and managers. This “Apollo Mission Familiarization for Constellation Personnel” project is accessible via the web from any NASA center for those interested in learning answers to the question “how did we do this during Apollo?”     

Assessing the legacy of the Space Shuttle

This article reviews the core legacies of the Space Shuttle program after 25 years and suggests that, while it was not an unadulterated success, on balance the Shuttle served a valuable role in the development of spaceflight and deserves an overall positive assessment in history. There are five core legacies that deserve discussion. First, the Space Shuttle has a reputation as a mistake resulting from a policy failure that should never have been pursued. Second, it has been criticized as a program that prohibited other paths for the US space program. Third, and more positively, the Space Shuttle provided more than two decades of significant human spaceflight capability and stretched the nature of what could be accomplished in Earth orbit much beyond where it had previously been. Fourth, it served as a relatively flexible platform for scientific activities. Finally, and perhaps most significantly since the US human spaceflight program has always been focused on national prestige, the Space Shuttle served well as a symbol of American technological verisimilitude.     

Shuttle avionics verification and integration testing

The Space Shuttle Orbiter employs a fly-by-wire control system of 200 major avionic hardware devices interfacing with five flight computers through a complex data bus system. Responses to man-in-the-loop commands are dependent on the flight software. Early program development testing of the computer and avionic hardware has been accomplished at Rockwell International's Shuttle Avionics Development Laboratory (ADL). Hardware development has led to complete multi-string system testing and flight software evaluations. This paper provides an overview of the ADL. Its role and test capabilities in support of Shuttle development are defined. The nature of computer driven test programs for the Orbiter displays, the Digital Autopilot, and flight software development describe the test bed provided by the ADL.     

Survey of mission evolution and flexibility in the Space Shuttle program

Given the diversity of missions it has accomplished and the myriad of adaptations it has undergone, the US Space Shuttle is widely regarded as a highly flexible space vehicle. With the Shuttle’s upcoming 2011 retirement, it is instructive to survey the history of this vehicle’s flexibility for the insights it can provide to the design and characterization of flexibility in future space systems. Data are presented on the evolution of mission requirements over time for 120 missions performed by the Space Shuttle over a period of some 27 years. Distinct trends in the time domain – as well as their causes – are identified and discussed, and early manifest plans from 1982 serve as a confirmation that these trends were not originally anticipated. Eight examples are then presented of engineering modifications that allowed the Shuttle to adapt and accommodate these requirement changes. Several additional instances of Shuttle flexibility are explored, such as post-Columbia disaster modification, upgrade programs and derived vehicles, and one case in which flexibility was inhibited by an early design decision.     

Priorities in space for the USA

This article follows the story of Shuttle development, in the context of the history of the US space programme from Apollo to the Space Station. The Shuttle was chosen as one of a series of ‘space spectaculars’ and has proven to be prohibitively expensive and unreliable, practical only for a very limited number of specialized missions. The Space Station, too, cannot be economically supplied, even if the USA could afford to build it. The author concludes that NASA should cancel the Space Station and the replacement orbiter for Challenger, and engage on a major programme of launch vehicle development, independent of the US military. The aim should be a dramatic reduction of launch vehicle costs, making spaceflight practical, and a truly independent NASA which could restore the USA to space preeminence.     

The future of human spaceflight.

After the Apollo Moon program, the international space station represents a further milestone of humankind in space, International follow-on programs like a manned return to the Moon and a first manned Mars Mission can be considered as the next logical step. More and more attention is also paid to the topic of future space tourism in Earth orbit, which is currently under investigation in the USA, Japan and Europe due to its multibillion dollar market potential and high acceptance in society. The wide variety of experience, gained within the space station program, should be used in order to achieve time and cost savings for future manned programs. Different strategies and roadmaps are investigated for space tourism and human missions to the Moon and Mars, based on a comprehensive systems analysis approach. By using DLR's software tool FAST (Fast Assessment of Space Technologies), different scenarios will be defined, optimised and finally evaluated with respect to mission architecture, required technologies, total costs and program duration. This includes trajectory analysis, spacecraft design on subsystem level, operations and life cycle cost analysis. For space tourism, an expected evolutionary roadmap will be described which is initiated by short suborbital tourism and ends with visionary designs like the Space Hotel Berlin and the Space Hotel Europe concept. Furthermore the potential space tourism market, its economic meaning as well as the expected range of the costs of a space ticket (e.g. $50,000 for a suborbital flight) will be analysed and quantified. For human missions to the Moon and Mars, an international 20 year program for the first decades of the next millennium is proposed, which requires about $2.5 Billion per year for a manned return to the Moon program and about $2.6 Billion per year for the first 3 manned Mars missions. This is about the annual budget, which is currently spend by the USA only for the operations of its Space Shuttle fleet which generally proofs the affordability of such ambitious programs after the build-up of the International Space Station, when corresponding budget might become again available.     

Risk management in international manned space program operations

New, innovative joint safety policies and requirements were developed in support of the Shuttle/Mir program, which is the first phase of the International Space Station program. This work has resulted in a joint multinational analysis culminating in joint certification for mission readiness. For these planning and development efforts, each nation's risk programs and individual safety practices had to be integrated into a comprehensive and compatible system that reflects the joint nature of the endeavor. This paper highlights the major incremental steps involved in planning and program integration during development of the Shuttle/Mir program. It traces the transition from early development to operational status and highlights the valuable lessons learned that apply to the International Space Station program (Phase 2). Also examined are external and extraneous factors that affected mission operations and the corresponding solutions to ensure safe and effective Shuttle/Mir missions.     

New microgravity fundamental physics research areas in the ISS era

NASA's microgravity fundamental physics program has used the Space Shuttle to perform high resolutions experiments in space. As we come to the end of the Shuttle era, we will begin to perform research aboard the ISS. A large stable of ground based experiments have been selected from NASA Research Announcements in a variety of disciplines. These investigations will form the backbone from which to select future flight candidates. Research in Laser Cooling and Atomic Physics will enable us to operate highly precise clocks in space. Low temperature physics experiments will use a liquid helium facility with a six-month lifetime. This facility can also support experiments in gravitational physics. Researchers in biological physics will be offered an opportunity to develop future experiments that can benefit from space experimentation. An overview of the future research directions and the benefits to the community of performing research aboard the ISS will be presented.     

Using computer graphics to enhance astronaut and systems safety.

Computer graphics is being employed at the NASA Johnson Space Center as a tool to perform rapid, efficient and economical analyses for man-machine integration, flight operations development and systems engineering. The Operator Station Design System (OSDS), a computer-based facility featuring a highly flexible and versatile interactive software package, PLAID, is described. This unique evaluation tool, with its expanding data base of Space Shuttle elements, various payloads, experiments, crew equipment and man models, supports a multitude of technical evaluations, including spacecraft and workstation layout, definition of astronaut visual access, flight techniques development, cargo integration and crew training. As OSDS is being applied to the Space Shuttle, Orbiter payloads (including the European Space Agency's Spacelab) and future space vehicles and stations, astronaut and systems safety are being enhanced. Typical OSDS examples are presented. By performing physical and operational evaluations during early conceptual phases. supporting systems verification for flight readiness, and applying its capabilities to real-time mission support, the OSDS provides the wherewithal to satisfy a growing need of the current and future space programs for efficient, economical analyses.     

Preparing EMU for Space Station

In today's fiscally constrained environment, it can be expected that systems designed for one space program will increasingly be used to support other programs. The example of the U.S. extravehicular mobility unit (EMU), designed for use with the Space Shuttle, and now part of the baseline for the International Space Station (ISS) program, illustrates the adaption process. Certifying the Shuttle's EMU for use aboard ISS requires addressing three fundamental issues: Identifying new ISS requirements to be imposed on the EMU. Extending Shuttle's EMU on-orbit service interval to meet ISS's longer missions. Certifying Shuttle's EMU to meet new environments unique to ISS. Upon completion of the certification process, Shuttle's EMU will meet all requirements for supporting both the Shuttle and ISS program. This paper discusses the processes for addressing these issues and progress to date in achieving resolution.     

Lunar base development missions

On 20 July 1969, humankind first set foot on our Moon. Since then we have developed the Space Shuttle, explored most of the planets, cooperated in the development of the International Space Station, and expanded our knowledge of the universe through use of systems such as the Hubble Space Telescope and the Mars Pathfinder. After just five human follow-on missions to our Moon, we have returned robotically only twice to orbit, to map the surface and explore for resources.

The indication of the presence of hydrogen concentration at the poles of our Moon found by Lunar Prospector has added a new perspective for groups studying and implementing future lunar missions. Plans for nearterm missions such as the European Space Agency (ESA) “Euromoon 2000”, the Japanese Lunar A and Selene, and the Mitsubishi ”Earthrise 2001” Project, along with follow-on phases to the Lunar Prospector, are the beginning of humankind's return to the Moon. Organizations such as the International Academy of Astronautics have long championed the “Case for an International Lunar Base,” and a vision of a commercially-based lunar program has been outlined by several groups. A Lunar Economic Development Authority (LEDA) promoted by the United Society in Space was promulgated by the filing of articles of incorporation in the state of Colorado on 4 August 1997. This non-profit corporation has as its goal the orderly development of the Moon, through issuance of bonds to international private citizens and business entities who care to invest in its long-term development.

This paper draws from the works of the aforementioned, and specifically from the International Academy of Astronautics Lunar Base Committee, to structure a series of architectures leading toward eventual international commercial colonization of the lunar surface. While the prospect of fully reusable transportation systems utilizing fully developed lunar resources to perpetuate the permanent lunar infrastructure is enticing, this is a goal. We must utilize our current and near-term capabilities to re-initiate human lunar presence, and then build on emerging technologies to strengthen our capabilities. Humankind's return to the Moon is a part of our destiny. We can return in the near future, and then proceed to a commercial, permanent settlement in the 21st century.     

Phase 1 research program overview

The Phase 1 research program was unprecedented in its scope and ambitious in its objectives. The National Aeronautics and Space Administration committed to conducting a multidisciplinary long-duration research program on a platform whose capabilities were not well known, not to mention belonging to another country. For the United States, it provided the first opportunity to conduct research in a long-duration space flight environment since the Skylab program in the 1970's. Multiple technical as well as cultural challenges were successfully overcome through the dedicated efforts of a relatively small cadre of individuals. The program developed processes to successfully plan, train for and execute research in a long-duration environment, with significant differences identified from short-duration space flight science operations. Between August 1994 and June 1998, thousands of kilograms of research hardware was prepared and launched to Mir, and thousands of kilograms of hardware and data products were returned to Earth. More than 150 Principal Investigators from eight countries were involved in the program in seven major research disciplines: Advanced Technology; Earth Sciences; Fundamental Biology; Human Life Sciences; International Space Station Risk Mitigation; Microgravity; and Space Sciences. Approximately 75 long-duration investigations were completed on Mir, with additional investigations performed on the Shuttle flights that docked with Mir. The flight phase included the participation of seven US astronauts and 20 Russian cosmonauts. The successful completion of the Phase 1 research program not only resulted in high quality science return but also in numerous lessons learned to make the ISS experience more productive. The cooperation developed during the program was instrumental in its success.     

Space platforms: A cost effective evolution of Spacelab operation

The Shuttle/Spacelab mode of space operations will soon provide ready access to space for a wide varity of experimenters. When the full capabilities of this system are utilized, an important tool will have been added to the research and development phases of the various disciplines. Although significant benefits can now be envisioned from using these systems, it has become evident that additional benefits to the users could be achieved if some of the available resources were augmented. Those resources include: power, thermal control; duration on orbit; stability; and orientation.This paper reports planning efforts in progress to determine what augmentation these systems should provide. To properly bound the study effort, a projection of the potential Spacelab activity through the 1980 decade is developed. Three major augmentation systems are examined and the benefits provided by each are outlined. One of these systems, the Science and Applications Space Platform, represents a very attractive concept and the potential cost effectiveness is examined in detail. After these analyses are completed, general conclusions on the cost and other benefits of Space Platforms are provided.     

Physiology, medicine, long-duration space flight and the NSBRI

The hazards of long-duration space flight are real and unacceptable. In order for humans to participate effectively in long-duration orbital missions or continue the exploration of space, we must first secure the health of the astronaut and the success of such missions by assessing in detail the biomedical risks of space flight and developing countermeasures to these hazards. Acquiring the understanding necessary for building a sound foundation for countermeasure development requires an integrated approach to research in physiology and medicine and a level of cooperative action uncommon in the biomedical sciences. The research program of the National Space Biomedical Research Institute (NSBRI) was designed to accomplish just such an integrated research goal, ameliorating or eliminating the biomedical risks of long-duration space flight and enabling safe and productive exploration of space. The fruits of these labors are not limited to the space program. We can also use the gained understanding of the effects and mechanisms of the physiological changes engendered in space and the applied preventive and rehabilitative methods developed to combat these changes to the benefit of those on Earth who are facing similar physiological and psychological difficulties. This paper will discuss the innovative approach the NSBRI has taken to integrated research management and will present some of the successes of this approach.     

The US–Europe technology gap in space transportation: the view from the USA

This paper examines the debate within the USA over how to meet the perceived competition from the successful European Ariane launcher and the loss of US market share for space launch services that it represented. In particular, it explores the origins of the 1983 Reagan Administration policy to turn over expendable launch vehicle production and operation to private industry. The Administration's other decisions to: (1) use the Space Shuttle to fly all government payloads, and (2) allow NASA to market Space Shuttle services commercially, conflicted with this commercialization policy. These policies effectively caused US industry to delay entry into the international competition for launch services until after the loss of the Space Shuttle Challenger in January 1986.