A key element in these studies is the provision of bioinstrumentation to measure the dynamic response of living systems to various stresses. The toxicity of oxygen at various pressures is being determined in several species of animals preliminary to human tests in fiscal year 1969. Experiments have shown that excessive oxygen pressure must be avoided since it can cause damage to lungs, kidneys, and other organs. Hormones and their control of stress reactions are being studied in animals at the cellular level, as well as in humans under stress. Further tests are necessary to establish whether a low hormone level is a warning of trouble to come. In the course of these space oriented studies, there sometimes are very worthwhile discoveries with other medical applications. For example, studies at Ames on hormones from the pituitary gland have resulted in the discovery of an enzyme which possibly may be used to produce human growth hormones from bovine growth hormones. Many people suffer from lack of this hormone and there is presently no adequate source of supply.

In Fiscal Year 1969, extensive studies of the effects of solar flares on mammalian tissue will be possible as a result of the development of a solar flare simulator for NASA by the University of California. Berkeley. Another area of increasing research effort in Fiscal Year 1969 will be the bacteriological aspects of long-term space flight. Environmental factors in such flights could possibly cause nonpathogenic organisms to become pathogenic, alter the mechanisms of infection and the immunological mechanisms, and result in cross-infection of space crew members.

In aviation, major effort will continue on studies of the psychoacoustic effects of aircraft noise and sonic boom. The physical characteristics of aircraft noise are being measured while families residing near eight major airports in the United States are questioned regarding their reactions to this noise.

Life Support and Protective Systems

The most critical technology problem area is life support. The logistics saving by recycling water and oxygen is most desirable, but limited ground studies have indicated that available techniques for achieving this do not live up to expectations when they are embodied in a total life support system where each unit depends on the output of another. A manned environmental chamber test is planned in Fiscal Year 1968 to test the water loop for a 60-day period. Of particular interest will be inventory and control of bacteria during such a run. Based on what is learned from this and other research, new subsystems must be developed with emphasis on maintainability and reliability.

The developments in new protective space suit concepts are promising, particularly new hard suit concepts in which man can operate with very little performance decrement because of easier mobility of the joints when the suit is pressurized. These are so promising that increased effort will include studies of application of these concepts to soft clothsuits to improve donning, and increase mobility and performance so that their operating pressure can be increased to that of the spacecraft. In aviation a new aircraft seat design is being developed which will absorb energy and provide the occupant more crash injury protection.

Man-Systems Integration

To ensure man's effectiveness in advanced aircraft and space systems, extensive studies are underway on the utilization of man in complex systems-as an operator and as a manager. In flight management, man has an increasingly complex role in assessment of the flight situation, the judgment of the significance of unscheduled events, and exercise of command-control functions. Emphasis will increase on methods of improving habitability of working and living areas of manned spacecraft times.

The development of extravehicular technology is a pacing item for man's work in space on astronomical telescopes, structures assembly, and crew and cargo transfer. Recommendations of the Astronomy Missions Board will influence study efforts in Fiscal Year 1969 on manned engineering operations in orbit including maintenance, repair, and equipment refurbishment and the development of worksite technology, tools, and work support systems. Conventional earth-type tools have been relatively ineffective. Our simulation techniques have proven that the development of tools and work techniques in the weightlessness of orbital flight is now possible. In aviation, the air crew workload is being studied in order to reduce stress and fatigue and increase safety.

Biotechnology Flight Projects

In Fiscal Year 1969, a Scout launch of a vestibular experiment is planned to permit study of the action in weightlessness of the basic cells in the frog's balance mechanism that is similar to man's inner ear (otolith). Other physiological experiments are being defined by the Ames Research Center, the Langley and Electronics Research Centers, and Manned Spacecraft Center.

13. BASIC RESEARCH, $22,000,000

This program supports fundamental research in the physical and mathematical sciences. It is aimed at providing an understanding of the physical phenomena pertinent to other NASA programs concerned with current and future aircraft and space activities. The research is carried out principally in NASA's Centers supplemented by investigations at universities, industrial research laboratories, and other Government research centers. Fundamental understanding of physical phenomena in many fields of science is required to develop the technology for NASA's programs. Basic research in NASA, therefore, must encompass a wide spectrum of disciplines. It ranges from very fundamental studies into the nature and properties of atoms and molecules to the more applied research areas of determining the best materials for the supersonic transport airplane.

The Basic Research program is divided into four broad disciplines: fluid physics, electrophysics, materials, and applied mathematics. Fluid dynamics research covers the three general areas of aeronautical fluid dynamics, entry fluid physics, and internal fluid mechanics of propulsion and power systems including the problems of clear air turbulence, sonic boom, aerodynamic heating and aerodynamic control of high speed aircraft. Reentry research focuses on improved understanding of the parameters which influence heating, the ablative response of the heat shield, and on the three dimensional flow fields about maneuver

able bodies. Fluid dynamic principles were applied to study blood circulation. Existing test data were analyzed in an attempt to develop simple and more precise circulatory diagnostic procedures.

The electrophysics program is to obtain new knowledge of the effects of acoustic, gravitational, electric and magnetic forces on the electronic, nuclear, atomic and molecular constituents of matter. New information in this area is the source not only for advances in the technology programs of electronics, space power and space propulsion, but also for the exploration and understanding of complex phenomena in space; for example, the interaction of the charged particles of the solar wind with the magnetosphere, and the determination of the motion of the Earth's magnetic field.

Materials research has as its objective the understanding of the characteristics and behavior of materials. It ranges from studies into the fundamental properties of solids to investigations of how and why engineering materials fail. Increasing emphasis is being placed on the behavior of electrons in solids and the effect of corrosive environments on metals and polymers over a wide range of temperatures. Research on mechanisms for improving the strength of composite and ceramic materials is continuing. The understanding of all such materials will enable advances to be made in the utilization of both currently available as well as newly developed materials to advanced aircraft and more sophisticated spacecraft.

The applied mathematics program is concerned with the improvement of mathematical techniques required for problems in aerospace science and technology. A mathematical approach is often the most feasible and economical for planning experiments. It is also a necessary basis for precise and reliable designing of the complicated and expensive pieces of hardware needed for various NASA operations. For example, mathematical research in numerical analysis, by developing faster and more effective computation procedures, has reduced the cost of digital simulation mission studies necessary for the successful design of such items as the Saturn V vehicle.

14. SPACE POWER AND ELECTRIC PROPULSION SYSTEMS, $42,300,000

The objective of the space power and electric propulsion systems program is to determine the associated technologies required to adequately support potential future missions; and by application of effective research and exploratory development to improve or establish these technologies to the degree required to insure eventual successful development for future missions.

Current estimates of future mission power system requirements encompass a wide range of power, life and mission environments. No one power system can meet these varied requirements. The space power program is aimed at providing the research and technology necessary for the improvement and/or development of a limited number of solar, chemical and nuclear systems for anticipated auxiliary power and electric propulsion mission requirements ranging from watts to kilowatts in the 1970's to megawatts in the 1980's.

The early application of solar powered electric thrusters for spacecraft position control and for small, automated, interplanetary spacecraft continues to be a major goal of the electric propulsion program. Experience to date from the ATS (applications technology satellite)

flight program coupled with the design and ground evaluation of typical thruster systems confirms their potential advantages of spacecraft use. The proposed SERT (space electric rocket test) flight, the continuing ATS program and the ground technology program are essential steps toward the goal of early application.

Supporting Research and Technology

The objective of the nuclear electric power technology program is to provide a broad option and design basis for the selection and evaluation of energy conversion equipment to be used in advanced nuclear electric power systems for future space missions. The primary program emphasis continues to be on a limited number of energy conversion concepts, for example, the Brayton, Rankine and thermionic systems, to meet the anticipated broad range of power requirements from watts and kilowatts in the 1970's to megawatts in the 1980's. The technology underlying these systems is long range and requires sustained effort to establish engineering data on new materials, working fluids and components at high temperatures never before used in power systems. The chemical power system tcehnology program is primarily concerned with increasing the usefulness of fuel cells and batteries for a wide range of applications ranging from low earth orbital satellites to planetary landers. Significant improvements such as metal-gas batteries and new engineering concepts for fuel cells appear feasible based on previous years' work. During Fiscal Year 1969 emphasis will be directed toward evaluating these concepts in breadboarded systems.

The solar power system technology program continues to focus on solar cell systems with special attention directed toward the requirements emphasized by consideration of high power (kilowatt) systems. Research aimed at reducing system cost, area and weight, as well as improving resistance to the space environment, will be continued in Fiscal Year 1969.

Continued progress is being made in the electric thruster technology program toward the goal of early mission application. In previous years emphasis in the primary propulsion program has been on obtaining suitable thruster system performance and endurance. In Fiscal Year 1969 emphasis will be directed toward evaluating and solving the problems of solar powered electric propulsion systems representative of those that could be utilized to propel small, automated, interplanetary spacecraft. Based on results obtained in Fiscal Year 1966, 1967, and 1968 the operational use of resistojets (electrically heated gas thrusters) for spacecraft position control is scheduled on the ATS D & E satellites which also will carry ion engine experiments. During fiscal Year 1969 the auxiliary propulsion program emphasis will be directed toward electrostatic thruster systems to achieve the benefits of high specific impulse and electrical thrust vectoring associated with this type of thruster and toward higher temperature resistojets for large orbiting satellites.

Space Electric Rocket Test (SERT)

The overall objective of the SERT flight program is to provide information on the operations of electric thruster systems in the space environment. SERT I successfully demonstrated that an ion beam. could be neutralized in space. A second flight is planned for 1969 to provide a long term evaluation (minimum of 6 months) of the per

formance and reliability of an ion thruster system and to study the effects of ion engines on other spacecraft components such as radio frequency interference. SERT II represents the next major step in the development and acceptance of electric thrusters for prime propulsion of interplanetary spacecraft. Current plans are to utilize a THORAD-Agena vehicle for launch of SERT II during Calendar Year 1969.

SNAP-8 Development

The objective of this technology project is to conduct the ground development of a 10,000 hour, 35-kilowatt nuclear electric generating system suitable for space applications in the 1970's and beyond. Principal potential applications for SNAP-8 are large earth-orbiting space stations, lunar exploration, direct TV broadcast satellites and utilimately, manned interplanetary missions.

In the past year priority has been placed on developing solutions to the major life-limiting problems found in the boiler and turbine from previous development testing and on endurance testing of the other major components of the power conversion system in small component loops. During this period the first SNAP-8 component, the lube/coolant pump, passed the 10,000-hour endurance test milestone.

The budget request for Fiscal Year 1969 provides primarily for the continued life development of the power conversion system components toward the 10,000-hour mark in component loops. It is planned to complete a 2,500-hour demonstration of the life capability of all major components in the bread-boarded SNAP-8 power conversion system.

15. NUCLEAR ROCKETS, $11,700,000

The objective of the Nuclear Rockets program is to provide rocket engine propulsion system for application to high-energy, high pay. load mission requirements of the future. This program has funded research to provide nuclear engine systems that have been statically tested, producing 50,000 pounds of thrust for periods up to 1 hour. Additionally, the program has funded the investigation and evaluation of advanced rocket concepts which may offer improvements in nuclear rocket engine technology.

Due to its high efficiency compared to that achievable with chemical rockets, the nuclear rocket provides a vastly increased performance capability for use in future space exploration activities. Installation of a nuclear stage as a third stage on the Saturn V would enable the maneuvering of large payloads in earth orbit with large changes in orbital planes and in orbital altitude, including the positioning of very heavy payloads in a synchronous orbit. It would also increase substantially the payload that could be carried to the moon for extended lunar missions or for the support of future lunar base activities. Nuclear propulsion would also reduce by several million pounds the weight of the space vehicle required to be launched from earth orbit for manned planetary missions.

The nuclear rockets program is a joint AEC-NASA effort, managed by a single office, the Space Nuclear Propulsion Office, which was established by interagency agreement between AEC and NASA. The headquarters office is at Germantown, Md. Supporting research and technology development work is conducted both in AEC laboratories