This is the transcript of the unclassified portion of a hearing before two subcommittees of the U.S. House of Representatives. It includes testimony and prepared statements from the Deputy Director of the Defense Advanced Research Projects Agency and the Deputy Chief of Naval Operations of the U.S. Navy. Advances in submarine quieting threaten the anti-submarine warfare advantage. These quiet submarines pose a serious threat to the sea lanes of communication, and potentially a submarine-launched cruise missile threat.

Sonar and Underwater Acoustics brings together all the concepts necessary for designers and users of sonar systems. Unlike other books on this subject, which are often too specialized, this book is accessible to a wider audience. The first part focuses on the acoustic environment, antenna structures, and electric acoustic interface. The latter provides knowledge required to design, as well as the development and implementation of chain processes for an active sonar from the conditioning input to output processing. The reader will find a comprehensive range of all problems encountered in underwater acoustics for a sonar application, from physical phenomena governing the environment and the corresponding constraints, through to the technical definition of transducers and antennas, and the types of signal processing involved. In one section, measures in underwater acoustics are also proposed.

The AN/SQS-26 long-range, echo-ranging sonar surpassed predecessor production sonars by adding an over-the-horizon detection capability and exploiting the surface duct, bottom bounce, and convergence zone sound propagation paths from a hull-mounted sonar on a surface ship to a submarine target. This history of the AN/SQS-26 program details the nature of the technical problems encountered and the solutions found to address them, as well as the influence of international events on the objectives and support of the program. The critical contributions made by numerous personnel and organizations to the development program are documented, and the arc of the AN/SQS-26 program's success is traced from early concept formulation through full-scale experimentation and development to operational evaluation and full deployment in the Fleet. The AN/SQS-26 served as the antisubmarine warfare (ASW) sonar on U.S. destroyers and cruisers for decades, and this versatile sonar became a key factor in the U.S. Navy's quest for ASW superiority in the Cold War era. The first edition was published by the Naval Undersea Warfare Center Division, Newport, RI, in 2003. This edition makes the historical material in the book available for use by academia, research laboratories, and fleet units interested in ASW and the principles of sonar.

"From the very first submarine in 1620 to the defense systems and weaponry used on modern submarines, this book uses diagrams, stories, and ... imagery to present a ... history of submarines and the technology used to operate them"--Provided by publisher.

The Department of the Navy strives to maintain, through its Office of Naval Research (ONR), a vigorous science and technology (S&T) program in those areas considered critically important to U.S. naval superiority in the maritime environment, including littoral waters and shore regions. In pursuing its S&T investments in such areas, ONR must ensure that (1) a robust U.S. research capability to work on long-term S&T problems in areas of interest to the Department of the Navy and the Department of Defense is sustained, (2) an adequate supply of new scientists and engineers in these areas is maintained, and (3) S&T products and processes necessary to ensure future superiority in naval warfare are provided. One of the critical areas for the Department of the Navy is undersea weapons. An Assessment of Undersea Weapons Science and Technology assesses the health of the existing Navy program in undersea weapons, evaluates the Navy's research effort to develop the capabilities needed for future undersea weapons, identifies non-Navy-sponsored research and development efforts that might facilitate the development of such advanced weapons capabilities, and makes recommendations to focus the Navy's research program so that it can meet future needs.