By their challenging nature, NASA programs are particularly demanding of technological input. Meeting the aeronautical and space goals of the past four decades has necessitated leading edge advancements across a diverse spectrum that embraces virtually every scientific and technological discipline. Technology is simply knowledge and, like other forms of knowledge, it is often broadly applied and transferable. For that reason, the vast storehouse of technology NASA has built is a national resource, a bank of knowledge available for commercial applications and enhancements to the quality of...

Since 1973, this publication has provided you with examples of products and services developed as a direct result of the transfer of NASA developed technologies to private industry. Then-we featured fire retardant materials; now-we talk about non-invasive cardiac monitors. Then-we reported about air pollution detection devices; now-we discuss sensors for environmental control. Then-we heard about vitreous carbon materials to be used for prosthetics; now-we design major propulsion systems used in the development of energy saving jet engines. Research and development in such areas as...

In 1958, a Congressional Mandate directed the National Aeronautics and Space Agency to ensure for the widest possible dissemination of its research and development results. Thus, the Scientific and Technical Information (STI) Program was born. While this program addressed mostly the timely dissemination of information to NASA, NASA contractors, other government agencies, and the public, technologies were identified that were clearly transferrable and applicable to industry for additional use in the development of commercial products and services. Such considerations spun off the Technology...

In this year 1999, we find ourselves on the threshold of a new century with its exciting discoveries to come and challenges to meet. Clearly in the last decades of this century, some of our most significant achievements in industry and our lifestyle have been brought about by new technology. We can expect this trend to continue and perhaps accelerate. Because of the great scientific and technical challenges of NASA missions, the demands of our programs result in many new technological discoveries. Meeting the NASA aeronautical and space goals has necessitated cutting-edge technical advances...

Some exploratory enterprises start with fanfare and end with a quiet burial; some start with hardly a notice, yet end up significantly advancing mankind's knowledge. The Interplanetary Pioneers more closely fit the latter description. When the National Aeronautics and Space Administration started the program a decade ago it received little public attention. Yet the four spacecraft, designated Pioneers 6, 7, 8, and 9, have faithfully lived up to their name as defined by Webster, "to discover or explore in advance of others." These pioneering spacecraft were the first to systematically orbit...

Some exploratory enterprises start with fanfare and end with a quiet burial; some start with hardly a notice, yet end up significantly advancing mankind's knowledge. The Interplanetary Pioneers more closely fit the latter description. When the National Aeronautics and Space Administration started the program a decade ago it received little public attention. Yet the four spacecraft, designated Pioneers 6, 7, 8, and 9, have faithfully lived up to their name as defined by Webster, "to discover or explore in advance of others." These pioneering spacecraft were the first to systematically orbit...

Catastrophic accidents are usually preceded by precursory events that, although observable, are not recognized as harbingers of a tragedy until after the fact. In the nuclear industry, the Three Mile Island accident was preceded by at least two events portending the potential for severe consequences from an underappreciated causal mechanism. Anomalies whose failure mechanisms were integral to the losses of Space Transportation Systems (STS) Challenger and Columbia had been occurring within the STS fleet prior to those accidents. Both the Rogers Commission Report and the Columbia Accident...

In some form, risk management (RM) has always been an integral part of virtually every challenging human endeavor. A formal and, at that time, qualitative RM process known as Continuous Risk Management (CRM) was introduced to NASA in the latter half of the 1990s. More rigorous quantitative RM processes including Risk-Informed Decision Making (RIDM) and an enhanced version of CRM have only recently been developed for implementation as an integral part of systems engineering at NASA. While there will probably always be vigorous debate over the details of what comprises the best approach to...

Since the writing of NASA/SP-6105 in 1995, systems engineering at the National Aeronautics and Space Administration (NASA), within national and international standard bodies, and as a discipline has undergone rapid evolution. Changes include implementing standards in the International Organization for Standardization (ISO) 9000, the use of Carnegie Mellon Software Engineering Institute's Capability Maturity Model(r) Integration (CMMI(r)) to improve development and delivery of products, and the impacts of mission failures. Lessons learned on systems engineering were documented in reports such...

Gallium Arsenide (GaAs) has been of interest as a photovoltaic material for many years. This interest arises primarily for three reasons. First, the bandgap of 1.42eV at 300 K is very nearly ideal for a photovoltaic device operating in our solar spectrum. Second, GaAs solar cells should be capable of operating at higher temperatures than silicon (Si) cells. Third, GaAs solar cells are expected to be very radiation resistant. This handbook provides a history of GaAs solar cell development; Photovoltaic equations are described along with instrumentation techniques for measuring solar cells;...