The first stealth submarine was German
Le submarine 480 (U-480) is a German submarine, The type VII Alberich, built on the principle of stealth : completely covered with rubber, it was undetectable to Allied sonar.
Its rubber coating was bristling with multiple holes of different diameters, whose main property was d & rsquo; absorbing waves of Allied sonar. This coating was called “Alberich”, also known as the anechoic tiles.
It was also equipped with all new acoustic guided torpedoes.
The U-480 destroyed four Allied ships at d & rsquo; a mission in the Channel 1944, but exploded on a sea mine in the minefield Brazier the D2 29 January 1945 at d & rsquo; a mission in southern & rsquo; Isle of Wight leaving no survivor among the 48 members & rsquo; crew.
Commissioned by & rsquo; Oberleutnant Hans-Joachim Förster, he sent to the bottom 14 000 barrels 4 days, despite a hunt at all times by the allied fleet and 92 underwater grenades randomly.
C & rsquo; is the 11 September 1944, off the & rsquo; Ireland, what, breaking his radio silence, by sending his staff results of his mission, that the allies will, for the first time, hear about the process Alberich. The British do not understand what's behind Alberich and think anti-grenades shield submarine or a new way to more powerful propulsion. But it & rsquo; is in discovering the character of & rsquo; Alberich, in an opera Wagner, capable, with a cape, to become invisible, that the allies will understand what constituted the & rsquo; German technological innovation.
At & rsquo; except for the U-480, none of the ten other submarines of this type was lost in combat.
L & rsquo; s & rsquo wreck, U-480 was not found that & rsquo; in 1998 at 58 meters deep with even much of its rubber coating.
After the war, anechoic tiles will not be used before the years 1970, when the Soviet Navy began to take its rubber submarines. Over time, technology progressing, tiles made it possible to dramatically reduce the acoustic signature of the submarine. The tiles of Russian submarines of the Akula class have a thickness d & rsquo; about 100 mm and reduce their acoustic signature 10 at 20 dB (10 % at 1 % of the initial power).
L & rsquo; US Navy began applying anechoic coatings on its submarines from 1988, and other marine followed quickly.
Thank you to my friend Eric and http://bigot45.free.fr
sources : wikipedia, www.libertyship.be, www.alberniproject.org