An U-Boat crew salutes the Nazi flag in 1944
"The Battle of the Atlantic was the only thing that ever frightened me."
And the U-Boats played a big role in the Battle of Atlantic.
The U27: First U-Boat launched by Nazi Germany in 1936
The first sea-going U-boat was U-27 launched in 1936. By 1939, a newer model had much better engine power and greater fuel carrying capacity - the Type VII B. By 1941, this had been overtaken by the Type VII C. These were so successful that over 600 were built.
British Aircraft carrier 'Courageous' sunk by a German sub U-29 in September, 1939
The Type VII C was 220 feet long and displaced about 770 tons on the surface. This U-boat had saddle tanks, four bow tubes and two stern tubes. Her diesel engines gave a top speed of 17 knots on the surface and 7.5 knots underwater. Its only drawback - a major one - was its limited range of operation; 6,500 miles at an average speed of 12 knots. However, her simple design meant that repairs at sea were relatively easy and the Type VII C had a very good reputation for reliability. The Type VII became the standard design for Germany's submarine fleet during World War Two.
The New York Times reports Roosevelt's resolve to make the Atlantic safer.
The collapse of France in June 1940 did a great deal to change submarine warfare. U-boats now had open access to the Atlantic from bases on the western coast of France. Prior to this, U-boats had to move either through the North Sea of the English Channel to get to the Atlantic. Both journeys were fraught with dangers. After June 1940, this problem disappeared.
INSIDE AN U BOAT
An Allies ship shoots off a depth charge
Allies losses in Battle of Atlantic
1939 : 222 ships sunk (114 by submarine)
1940 : 1059 ships sunk (471 by submarine)
1941 : 1328 ships sunk (432 by submarine)
1942 : 1661 ships sunk (1159 by submarine)
1943 : 597 ships sunk (463 by submarine)
1944 : 247 ships sunk (132 by submarine)
1945 : 105 ships sunk (56 by submarine)
An U-Boat under attack
However, the German war machine could not produce enough U-boats fast enough. The Kriegsmarine had developed its requirement strategy around the war being over quickly. 60 U-boats were launched in 1940 - but this represented just over one per week. In the same year, 32 had been lost in action and 2 damaged in accidents.
Allied planes guard convoys
Despite this, they managed to wreak havoc. Individual U-boat captains like Kretschmer were responsible for the sinking of 200,000 tons of shipping alone. If more U-boats had been at sea, the impact of the Battle of the Atlantic could have been far greater for Britain.
For all the success of the U-boats, the Allies were developing a large array of anti-submarine weapons including more modern depth charges, 'hedgehogs', 'squids' and more sophisticated radar equipment, including radar designed to see U-boats on the surface at night. While the U-boats were successful, they were also becoming more and more vulnerable to an attack.
GERMAN U BOAT PROPAGANDA FILM
U-Boat attacked by Allied planes!
Aircraft were fitted with ASV (Air to Surface Vessel radar). This allowed a plane to spot a U-boat on the surface but the U-boat could not pick up ASV on its radar receiver.
The Type XXI was an awesome weapon but too few were ever produced. The Allies could now bomb factories and submarine pens with great frequency and accuracy. Fuel depots were also a target. The Germans may have had a fine submarine on paper but producing it in numbers was a different matter. Dönitz informed Hitler that the first Type XXI would be ready by November 1944. Hitler ordered an earlier date and gave Albert Speer the task of getting the Type XXI produced. But with the Allies and the Russians closing in on both sides of Europe, constant bombing of factories etc, it was an impossible demand.
The Type XXI was commissioned in early 1945 and the first one, U-2511, went to sea just one week before Germany surrendered. On May 7th, 1945, Dönitz ordered all U-boats to cease hostilities.