Ever since David Bushnell invented the first underwater warship (the Turtle, which tried, unsuccessfully, to blow up the British frigate Eagle in New York harbor in 1776), naval men have dreamed of a true submarine, i.e., one which would practically never have to come to the surface. Last week Secretary of the Navy James Forrestal revealed that the Germans came dangerously close.
At the end of the war the Nazi Model 21 could stay submerged nine-tenths of the time. More amazing still: it achieved the speed of 18 knots under water—faster than it could travel on the surface.
Submarines normally travel only half as fast under water as on it. The Germans reversed this ratio by beefing up the electric batteries which power a submarine when submerged. Model 21 rarely had to surface because it used the “Schnorkel,” an extendable air pipe which enables a submarine to recharge the batteries by diesel while submerged (TIME, Feb. 19). In one 45-day patrol, Model 21 U-boat spent all but four days under water. Only drawback: cooped-up living conditions. Some 116 of the formidable Model 21s were built, but minor defects kept them from going to sea on real war patrols.
Other fantastic German inventions described last week by the Navy and U.S. and British technicians:
¶ A guided torpedo, “the Spider,” electrically controlled by means of a thin wire leash, which could be made to change its course or depth or even leap out of the water like a porpoise.
¶ A piloted rocket missile, with a 3,000-mile range, which its designer said could cross the Atlantic with passengers in 17 minutes.
¶ A coating for submarines and planes designed to prevent detection by radar.
¶ Processes for making synthetic butter, potable alcohol, soap and gasoline from coal.
¶ Supersonic wind-tunnels for studying missiles (like the V2) which move far faster than sound. The Navy is dismantling one such tunnel, will bring it to the U.S.
¶ Development of hydrogen peroxide as a high-powered fuel. Hydrogen peroxide, an unstable compound (H2O2), breaks down (into water—H20—and an atom of oxygen) with a large release of energy. The Germans used hydrogen peroxide in launching their V-1 and V-2 missiles, and were adapting it, with apparently promising results, to naval uses.
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