The fourth volume in the British Secret Projects series shows how the hopes of the time failed to see fulfillment. Following a scene-setting introduction, chapters will deal with test vehicles and guided weapons. This includes those developed for air defense, ballistic missile defense, anti-tank weapons, anti-ship ordnance, and stand-off weapons.

Hypersonic missiles--specifically hypersonic glide vehicles and hypersonic cruise missiles--are a new class of threat because they are capable both of maneuvering and of flying faster than 5,000 kilometers per hour. These features enable such missiles to penetrate most missile defenses and to further compress the timelines for a response by a nation under attack. Hypersonic missiles are being developed by the United States, Russia, and China. Their proliferation beyond these three could result in other powers setting their strategic forces on hair-trigger states of readiness. And such proliferation could enable other powers to more credibly threaten attacks on major powers. The diffusion of hypersonic technology is under way in Europe, Japan, Australia, and India--with other nations beginning to explore such technology. Proliferation could cross multiple borders if hypersonic technology is offered on world markets. There is probably less than a decade available to substantially hinder the potential proliferation of hypersonic missiles and associated technologies. To this end, the report recommends that (1) the United States, Russia, and China should agree not to export complete hypersonic missile systems or their major components and (2) the broader international community should establish controls on a wider range of hypersonic missile hardware and technology.

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. NASA SP-2007-4232

Delving into the Realm of Hypersonic Missiles In the ever-evolving landscape of military technology, hypersonic missiles stand as a vanguard of innovation, poised to transform the face of warfare. These marvels of engineering, capable of exceeding Mach 5, shatter the boundaries of conventional weaponry, offering unparalleled speed, maneuverability, and destructive power. Their emergence has ignited a global arms race, as nations scramble to develop and deploy these formidable weapons systems. This comprehensive exploration of hypersonic missile technology embarks on a journey through the fascinating realm of hypersonic flight. From its origins in science fiction to its current status as a critical component of modern military arsenals, we delve into the intricate physics, propulsion concepts, and guidance systems that propel these marvels of engineering. Along the way, we encounter the challenges and opportunities presented by hypersonic weapons, exploring their impact on global security and the prospects for arms control. A Glimpse into the Future of Warfare As hypersonic missiles continue to evolve, their implications for warfare grow ever more profound. Their ability to penetrate hardened defenses, attack with unprecedented precision, and evade traditional missile defense systems poses a significant threat to the strategic balance of power. Moreover, their potential applications extend beyond traditional warfare, raising concerns about their use in asymmetric conflicts and the disruption of international stability. Navigating the Ethical Landscape The development and deployment of hypersonic weapons raise complex ethical and legal considerations. The potential for devastating civilian casualties, the erosion of arms control agreements, and the increased risk of escalation demand careful consideration and responsible stewardship of this revolutionary technology. Seeking Cooperation in a New Era In the face of these challenges, international cooperation is essential to mitigate the risks associated with hypersonic weapons. Fostering dialogue and finding common ground on arms control measures can help prevent the proliferation of these destabilizing technologies and promote global security. A Call for Responsible Innovation As we explore the frontiers of hypersonic missile technology, we must remain mindful of its potential impact on the world we inhabit. Responsible innovation demands a commitment to transparency, accountability, and the pursuit of peace. It is our collective responsibility to harness the power of technology for the betterment of humanity, not for its destruction. Join us on this journey as we unravel the mysteries of hypersonic missile technology, unraveling its potential for both destruction and innovation. Together, we can shape the future of warfare and ensure that the pursuit of progress does not come at the cost of humanity's safety and security.

This study was undertaken in response to a request by the U.S. Air Force that the National Research Council (NRC) examine whether the technologies that underlie the concept of a hypersonic, air-launched, air-breathing, hydrocarbon-fueled missile with speeds up to Mach 81 can be demonstrated in time to be initially operational by 2015. To conduct the study, the NRC appointed the Committee on Review and Evaluation of the Air Force Hypersonic Technology Program, under the auspices of the Air Force Science and Technology Board.