The Type UB III represents the pinnacle in the design of German attack submarines during the First World War, and this project was
undoubtedly one of the best in the world, and during many years. After the war, some of these vessels served until 1935 with the Allied navies.
Thirty-seven units had been lost during the conflict and the rest had been surrendered to the Allies following the Armistice of November 1918.
As we can see in the illustration, the numerous units in this class shared a common layout while having many differences in the details.
The Type UB III began to be deployed in the mid 1917, when United States declared war on Germany. When the Allied merchant fleet started to
be organized in escorted convoys, it became more difficult to engage enemy shipping without being spotted by the escorting destroyers.
Nevertheless, these submarines performed very well, sinking 507 merchant ships - for a total of 1,212,553 gross register tonnes - and twelve
warships, including the pre-dreadnought battleship HMS Britannia in 1918.
After the war Germany had forbidden by the Treaty of Versailles to create a new submarine force. But German admirals had no intention of
allowing their nation to forget the knowledge of building submarines, and Germany started to manufacture slightly modified versions
of the Type UB III for exportation. Keeping the skills of German engineers polished by this means, eventually it was ordered the construction of a new coastal
attack submarine based on the Type UB III, but including improvements such as an all-welded construction and a set of electronic and
electromechanical devices. The result was the Type VII, the most common class of U-boat deployed by the Kriegsmarine during the Second World War.
Type UB III: 96 units (UB-48 to UB-133, UB-136, UB-142 to UB-145, UB-148 to UB-150, UB-154, UB-155)
Type: Attack submarine
Length: 55.30–57.80 meters
Beam: 5.76–5.80 meters
Draught: 3.67–3.85 meters
Displacement (surfaced): 508–555 tonnes
Displacement (submerged): 629–684 tonnes
Propulsion: 2 x shaft, 2 x Diesel engine 550 horsepower, 2 x electric motor 390 horsepower
Speed (surfaced): 13.2–13.9 knots (24.4-25.7 kilometers/hour)
Speed (submerged): 7.4-8 knots (13.7–14.8 kilometers/hour)
Range (surfaced): 7120–9090 nautical miles (13186-16834 kilometers) at 6 knots
Range (submerged): 50-55 nautical miles (92.6-101.9 kilometers) at 4 knots
Test depth: 50 meters
Armament: 5 x 500-millimeter torpedo tube (4 at prow, 1 astern), 10 x torpedo, 1 x 88 or 105-millimeter deck cannon