Air Defense of the United States: Strategic Missions and Modern Technology

Air Defense o f the United States Strategic Missions and Modern Technology William P. Delaney Strategic air defense of the United States was a high-interest topic in the 1950s and early 1960s. The concern was Soviet intercontinental bombers, and the United States had a substantial national air defense system. But by the mid-60s, any concern of attack by aircraft was eclipsed by the threat of intercontinental ballistic missiles. The lack of a means to effectively defend against these missiles caused a conscious decline in our air defense capability. The Strategic Defense Initiative (SDI)in 1983caused a resurgence of interest and controversy about national ballistic missile defense. A by-product of this national debate has been some rekindling of interest in the companion problem of strategic air defense. The interest in air defense has also been rejuvenated by the recent rapid advances in the technology of air-breathing vehicles. The United States has been the major innovator with the development of modern cruise missiles and stealthy manned aircraft.’ Other nations will certainly follow the U.S. This article is derived from presentations given at the U.S.-Canadian Strategic Air Defense Conference at Harvard University in February 1988 and the International Institute for Strategic Studies Workshop on Strategic Air Defense in November 1988. The original impetus for the work came from Dr. Arthur Charo, then at the Center for Science and International Affairs, Harvard University. My thanks to him and Professor Ash Carter of Harvard for their encouragement . Many other people provided helpful reviews and commentary. I did not follow all the advice I got, so the estimates and opinions of this article remain my own. This work was sponsored by the Department of the Air Force under Contract F19-628-85-C-0002. The views expressed are those of the author and do not reflect the official policy or position of the U.S. Government. William P. Delaney is an Assistant Director at the MZT Lincoln Laboratory. He has been involved in research and development on radar, missile defense and air defense systems for thirty years at Lincoln Laboratory. His experience includes an assignment at the Kwajalein test site for ICBM and ABM testing, and a tour in the Office of the Secretary of Defense with responsibilities for strategic defense systems. 1. On modern cruise missiles, see Richard K. Betts, Cruise Missiles Technology, Strategy, Politics (Washington, D.C.: Brookings, 1981). See also Rose E. Gottemoeller, Land Attack Cruise Missiles, Adelphi Paper No. 226 (London: International Institute for Strategic Studies [IISS],Winter 198788 ), for a more recent description of Soviet cruise missiles and their military rationale. References on stealthy manned aircraft are scarce due to the security classification that has surrounded these developments. See John A. Adam, ”How to Design An Invisible Aircraft,” ZEEE Spectrum, April 1988, for a general discussion of stealth techniques. Those with a more technical inclination International Security, Summer 1990 (Vol. 15, No. 1) 01990 by the President and Fellows of Harvard College and of the Massachusetts Institute of Technology 181 International Security 15:1 I 182 lead. The Soviets have had cruise missiles in their inventory for many years; their latest deployed submarine-launched cruise missile (SLCM), the SS-N21 , seems to be quite competitive in performance and modern technology with the first generation of U.S. cruise missiles. Today’s strategic air defense designer faces a challenging task because of these advances in air vehicle offense. Cruise missiles can arrive in large numbers, and they can be hard for the defense to find. Their observability to radar or other types of defense sensors can be reduced to low levels. They are physically small, and modern navigation techniques allow them to fly at low altitude where they can hide in the competing background of the earth’s surface. Stealthy manned aircraft present a similar set of challenges to the air defense designer. The main focuses of this article are the technical challenges and the defense system architecture problems caused by these advances in the air vehicle offensive capability. This article is a technical overview of air defense missions, components, and systems; it is not a discussion of strategic defense policy, and it is not...