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Sonar, Anti-submarine Warfare, and the Royal Navy, 1914-54
出版H.M. Stationery Office, 1984
主題History / Europe / Great Britain / GeneralHistory / Military / NavalTechnology & Engineering / Acoustics & SoundTechnology & Engineering / Military Science
ISBN01129042389780112904236
URLhttp://books.google.com.hk/books?id=5ja4AAAAIAAJ&hl=&source=gbs_api
註釋"This is the first history of the Royal Navy's part in research in underwater acoustics. Between 1914 and 1954 the submarine evolved into an underwater warship whose most dangerous weapon was its ability to hide in a mass of water. Of the many techniques that were tried to deprive it of that advantage, those based on sonar have been the most effective. At the beginning of the First World War, the British Navy had almost no means of tackling the danger of German U-boats. The use of hydrophones - underwater microphones - proved of limited value, and in 1917 work began on the development of an "active" detection device. This was based on French research into the capacity of certain crystals to act as transmitters and receivers of high-frequency sound waves. These move about four times faster through water than through air, but their exact speed varies with temperature, pressure and salinity - and, as scientists discovered, these differ considerably in different parts of the oceans. Another complication is that as sound travels away from whatever has produced it, its energy diminishes. As a result of this, and of the distortion caused by reflection from both surface and sea bed, the echo from a target has only a fraction of the energy of the transmitted sound impulse. In the mid 1920s experiments were begun with magnetostrictive transducers, first used in the British Navy's attack sonar sets after the Second World War. They in turn have, for certain purposes, been replaced by electrostrictive ceramic transducers. In 1919 the average echo range was about 457m (500 yds); in the Second World War it was about 1.2km (1300 yds); at the end of this history it had increased to several miles. This book, through careful research, has brought together in a clear and absorbing way the different aspects of British naval development: the impact of tactical and strategic needs on that development; the evolution of sonar; and the transformation of small-scale technical research into a complex organisation involving government and industry." -- back of book.