T. A. Heppenheimer's acclaimed chronicle of rockets, politics, and the pioneers who dared to reach beyond humanity's limits.

"The most comprehensive, up-to-date, and best written history of space flight there is."—The Times (London)

"A lively account of the development of space activities in the U.S. and the Soviet Union . . . as good a one-volume overview of space as exists.—Scientific American.

"Countdown is by far the best history of space flight I have ever read. It is detailed, lucidly written for the layman, and full of fascinating stories.—Adrian Berry, Daily Telegraph.

"Science writer Heppenheimer's readable account provides a timely historical overview of the early visionaries, the engineers, and the geopolitical forces that placed men on the moon and created today's aerospace industry. . . . A thoughtful analysis that is highly recommended.—Library Journal.

"By far the most significant and technically insightful account of the ventures into the space environment I have seen. . . . [Heppenheimer] concentrates unerringly on key elements, both technical and managerial, in this account of man's initial space ventures."—Lee Atwood, Former president and chairman, North American Aviation Corporation.

"Like a skilled artisan, Heppenheimer weaves social, political, scientific, technological, military, and economic threads of the history of space flight into a tapestry that reveals fascinating patterns and themes."—Publishers Weekly

Hypersonics is the study of flight at speeds where aerodynamic heating dominates the physics of the problem. Typically this is Mach 5 and higher. Hypersonics is an engineering science with close links to supersonics and engine design. Within this field, many of the most important results have been experimental. The principal facilities have been wind tunnels and related devices, which have produced flows with speeds up to orbital velocity. Why is it important? Hypersonics has had two major applications. The first has been to provide thermal protection during atmospheric entry. Success in this enterprise has supported ballistic-missile nose cones, has returned strategic reconnaissance photos from orbit and astronauts from the Moon, and has even dropped an instrument package into the atmosphere of Jupiter. The last of these approached Jupiter at four times the speed of a lunar mission returning to Earth. Work with re-entry has advanced rapidly because of its obvious importance. The second application has involved high-speed propulsion and has sought to develop the scramjet as an advanced airbreathing ramjet. Scramjets are built to run cool and thereby to achieve near-orbital speeds. They were important during the Strategic Defense Initiative, when a set of these engines was to power the experimental X-30 as a major new launch vehicle. This effort fell short, but the X-43A, carrying a scramjet, has recently flown at Mach 9.65 by using a rocket. Atmospheric entry today is fully mature as an engineering discipline. Still, the Jupiter experience shows that work with its applications continues to reach for new achievements. Studies of scramjets, by contrast, still seek full success, in which such engines can accelerate a vehicle without the use of rockets. Hence, there is much to do in this area as well. For instance, work with computers may soon show just how good scramjets can become.

The Space Shuttle took shape and won support, and criticism, as part of NASA's search for a post-Apollo future. NASA had grown rapidly during the 1960s and the success of the piloted moon landings brought insistent demands that NASA should shrink considerably. In facing those demands, and in overcoming them to a degree, NASA extended our manned presence in space. Before anyone could speak seriously of a space shuttle, there had to be a widespread awareness that such a craft would be useful and perhaps even worth building. A shuttle would necessarily find its role within an ambitious space program; and while science-fiction writers had been prophesying such wonders since the days of Jules Verne, it was another matter to present such predictions in ways that smacked of realism. This book portrays NASA's search for continued manned space exploration after the success of Apollo. During 1969, with Nixon newly elected and the first astronauts setting foot on the Moon, NASA Administrator Thomas Paine led a push for a future in space that promised to be expansive. He aimed at nothing less than a piloted expedition to Mars, propelled by nuclear rocket engines that were already in development. En route to Mars, he expected to build space stations and large space bases. Almost as an afterthought, he expected to build a space shuttle as well, to provide low-cost flight to these orbiting facilities. Soon after Neil Armstrong made his one small step in the lunar Sea of Tranquillity, Paine received a cold bath in the Sea of Reality. Nixon's budget director, Robert Mayo, chopped a billion dollars from Paine's request. This brought an end to NASA's hopes for a space base and for flight to Mars. It appeared possible, however, to proceed with the space station and the Shuttle, as a joint project. The Shuttle drew particular interest within the Air Force, which saw it as a means to accomplish low-cost launches of reconnaissance satellites and other military spacecraft. Congress, however, was deeply skeptical toward the proposed shuttle/station, as both the House and Senate came close to killing it in 1970. NASA responded to this near-death experience by placing the station on the shelf and bringing the Shuttle to the forefront. Its officials needed political support that could win over doubters in Congress, and they found this support within the Department of Defense. The Air Force now found itself in a most unusual position. Its generals had worked through the 1960s to pursue programs that could put military astronauts in space. These programs had faltered. Yet here was NASA offering the Pentagon a piloted space shuttle. The Air Force gave its political support to the Shuttle, and NASA went on to quell the opposition on Capitol Hill. The OMB was a tougher opponent. These critics forced NASA to abandon plans for a shuttle with two fully reusable liquid-fueled stages, and to set out on a search for a shuttle design that would cost half as much to develop. Budget officials demanded a design that would be smaller and less costly, even though such a shuttle would have significantly less capability than the Air Force wanted. By shrinking the Shuttle, however, NASA won support where it counted. Caspar Weinberger, the OMB's deputy director, gave his endorsement late in 1971. Nixon also decided that the nation should have a shuttle. On the eve of decision, the key player proved to be OMB Director George Shultz. He decided that since the shuttle was to serve the entire nation, it should have the full capability for which NASA hoped and the Air Force demanded. Shultz's decision reinforced Nixon's, putting an end to the OMB's continuing demands to downsize the design. The consequence was the Space Shuttle as we know it today.

This significant new study of the decision to build the Space Shuttle explains the Shuttle's origins and early development. In addition to internal NASA discussions, this work details the debates in the late 1960s and early 1970s among policymakers in Congress, the Air Force, and the Office of Management and Budget over the roles and technical designs of the Shuttle. Examining the interplay of these organizations with sometimes conflicting goals, the author not only explains how the world's premier space launch vehicle came into being, but also how politics can interact with science, technology, national security, and economics in national government. The weighty policy decision to build the Shuttle represents the first component of the broader story: future NASA volumes will cover the Shuttle's development and operational histories.