U-boat is the anglicized version of the German word U-Boot , a shortening of Unterseeboot, which means "undersea boat" employed by Germany, particularly in World War I and World War II. The unrestricted submarine warfare of World War 1 and World War 2 came close to bringing England to its knees .
Germany was denied a submarine force after WW I . Despite the ban, Germany set up a clandestine uboat design office in Holland in 1922. In 1932, the Weimar government approved the building of 16 uboats . Donitz was given command of Germany's first post war uboat flotilla in 1935 and set about planning to succeed where the WW I uboats had failed .
Engine room of WWI uboat
At the outbreak of the war, Germany had three main types of uboats in construction . Type II was manoeuvrable and could crash dive in 25 seconds . their small sized and weapon loads led to their being stopped produced in 1941 . A majority of the uboats that fought in the battle of the Atlantic were type VIIs . These were built in large numbers with over 800 being built by the end of the war . This uboat carried between 11 and 14 torpedoes . Type IX uboats were designed for long range operations and could reach Indian Ocean and the Pacific without refueling . The Kriegsmarine's building schedule was based on the belief that there would be no war till the mid 1940s, when they hoped to match the British Navy . when war broke out in 1939, Germany only had 46 operational uboats . Between the wars, Donitz developed a new uboat tactic, the wolf pack , using groups of uboats to attack allied shipping .
German stamp WW 2
By the end of the war, the Type XXI uboats, the fastest ever built with a Schnorchel that let it operate as long as there was fuel could have wrought havoc in the allied navies, but like the Me-262 jet fighter in was produced to late and in too few numbers to have ant effect on the outcome of the war .
1st U Boat Flotilla U-Flottille Weddigen founded Sept 27, 1935
Uboat submariners captured by US Coast Guard
World War 1 uboats in color
Uboats in the Gulf
In 1942, with the U.S. military still gearing for battle, Hitler brought the war to America. In a little known mission, dozens of Nazi U-boats penetrated the Gulf of Mexico, attacking and sinking numerous merchant freighters and oil tankers. While experts thought they knew most of what went on there, their theories were challenged in 2001 when an underwater survey team discovered the wreck of U-166 on the Gulf's seafloor--over 140 miles distant from where records said she sank .
Documentary on Nazi U-boat technology
a documentary on German U-boats (short for Unterseeboot: underwater boat) includes some nice footage of a few impenetrable U-boat bunkers constructed at Adolf Hitler's suggestion. The reference to "slave laborers" is a misnomer unless one calls ALL prisoners everywhere on this planet "slave laborers". We also see a visit by the Japanese Imperial Navy. The narrator points out that they took both technology and tactics from the Germans. There's also very interesting footage of a Fa-330 or Bachstelze (literally "wagging tail") a sort of mini-helicopter that was towed from behind a surfaced U-boat providing an ingenius observation platform.
WWll in Colour-1941 U-Boat Campaign Against the U.S
Mini uboat Seehund Type XXVII , produced from 1944, two man crews, mini uboats sank 9 merchant ships . the Seehund's small size made it almost impossible for Asdic to get a return from her hull, while her very quiet slow speed running made her almost immune to detection by hydrophone. As Admiral Sir Charles Little, Commander-in-Chief, Portsmouth put it, "Fortunately for us these damn things arrived too late in the war to do any damage".
WWII German Cadets Study Diesel Engines at U-Boat Training School