SM U-2 (Austria-Hungary)

A view of U-2 showing her conning tower, two periscopes, and a ventilation mast (far left)
History
Austria-Hungary
Name	SM U-2
Ordered	24 November 1906
Builder	Pola Navy Yard, Pola
Laid down	18 July 1907
Launched	3 April 1909
Commissioned	22 June 1911
Refit	January–June 1915
Fate	Transferred to State of Slovenes, Croats and Serbs on 31 October 1918
State of Slovenes, Croats and Serbs
Name	U-2
Acquired	31 October 1918
Fate	Handed over to the Allied powers on 10 November 1918
Italy
Name	U-2
Acquired	9 November 1918
Fate	Ceded to Italy under the Treaty of Saint-Germain-en-Laye in 1920 and broken up at Pola
Service record
Commanders:	Klemens Ritter von Bezard 22 June 1911 – 10 May 1912[1] Karl Edler von Unczowski 10 May 1912 – 23 October 1914 Otto Zeidler 23 October 1914 – 15 February 1915 Karl Edler von Unczowski 15 February – 22 June 1915 Otto Kasseroller 22 June 1915 – 13 September 1917 Johann Ulmansky von Vracsevgaj 13 September 1917 – 15 March 1918 Othmar Printz 28 March – 1 September 1918 Johann Ulmansky von Vracsevgaj 1 September – 31 October 1918
Victories:	None[1]
General characteristics
Class and type	U-1-class submarine
Displacement	As built: 229.7 t (226 long tons) surfaced 248.9 t (245 long tons) submerged After modernization: 223.0 tonnes (219 long tons) surfaced 277.5 tonnes (273 long tons) submerged
Length	As built: 30.48 m (100 ft 0 in) After modernization: 30.76 m (100 ft 11 in)
Beam	4.8 m (15 ft 9 in)
Draft	3.85 m (12 ft 8 in)
Propulsion	As built: 2 × shafts 2 × gasoline engines, 720 bhp (540 kW) total 2 × electric motors, 200 shp (150 kW) total After modernization: 2 × diesel engines (replaced the gasoline engines)
Speed	10.3 knots (19.1 km/h; 11.9 mph) surfaced 6 knots (11 km/h; 6.9 mph) submerged
Range	950 nmi (1,760 km; 1,090 mi) at 6 knots (11 km/h; 6.9 mph), surfaced 40 nmi (74 km; 46 mi) at 2 knots (3.7 km/h; 2.3 mph), submerged
Test depth	40 meters (131 ft 3 in)
Complement	17
Armament	3 × 45 cm (17.7 in) torpedo tubes (two front, one rear); 5 torpedoes 1 × 37 mm (1.5 in) deck gun

SM U-2 or U-II was the second ship of the U-1 class of submarines or U-boats built for and operated by the Austro-Hungarian Navy (German: Kaiserliche und Königliche Kriegsmarine or K.u.K. Kriegsmarine). U-2 was designed by American naval architect Simon Lake of the Lake Torpedo Boat Company, and constructed at the navy yard in Pola. She was one of two Lake-designed submarines purchased as part of a competitive evaluation of foreign submarine designs after domestic proposals were rejected by the Navy.

Ordered on 24 November 1906, U-2 was laid down in July 1907 before being launched in April 1909. She was 30.48 meters (100 ft 0 in) long and displaced between 229.7–248.9 metric tons (226–245 long tons) depending on whether she was surfaced or submerged. An experimental design, U-2 included unique features such as a diving chamber and wheels for traveling along the seabed. Originally powered by gasoline engines for surface running, it was discovered during her sea trials throughout 1909 and 1910 that these engines were found to be incapable of reaching the submarine's contracted speed and posed a risk of poisoning the ship's crew. U-2 was commissioned in June 1911 and served as a training boat through 1914, though she was mobilized briefly during the Balkan Wars. U-2's design has been described by naval historians as a failure that was rendered obsolete by the time she was commissioned into the Austro-Hungarian Navy. Despite these criticisms, tests of her design provided information which the Navy used to construct subsequent submarines.

At the beginning of World War I, U-2 was in drydock awaiting new batteries and replacement diesel engines. This refit resulting in a changed bow for the ship as well as changes in her displacement. As part of this overhaul, U-2 was also fitted with a new conning tower. She returned to service as a training boat in June 1915. U-2 conducted reconnaissance cruises out of Trieste until she was declared obsolete in early 1918. The ship continued to serve in a training role at the submarine base on Brioni, but was at Pola at the end of the war. Facing defeat in October 1918, the Austro-Hungarian government transferred its navy to the newly formed State of Slovenes, Croats and Serbs in order to avoid having to hand its ships over to the Allied Powers. Following the Armistice of Villa Giusti in November 1918 however, U-2 was seized by Italian forces and subsequently granted to the Kingdom of Italy under the Treaty of Saint-Germain-en-Laye in 1920. Italy chose to scrap the submarine, and she was broken up at Pola later that same year without ever having sunk or damaged any vessels during her career.