Submarine: SM U-21
Kyler’s Kaiserliche Marine Blog
Submarine: SM U-21
Class: Type U 19
Length: 64.15 meters
Width: 6.10m
Height: 8.10m
Draft: 3.58m
Shafts: 2
Powerpoint: 2 Man Stroke 8-Cylinder Diesel Engines
Speed: 15.4 knots surfaced / 9.5 submerged
Range: 9,700 nautical miles Surface / 80 miles submerged
Crew: 4 Officer / 31 Enlisted
Weapons: 4 50cm torpedoes with 6 torpedoes with 88mm SK L/30mm deck gun.
The U-21 is the most famous of the four submarines. It was captained by Otto Hersing during almost the entire First World War. The submarine would the first to sink another ship with a propelled torpedo. It would survive the war only to be sunk by its crew to keep the submarine from the British.
The photo shows all four submarines of the class.
Source: Wikipedia