The U-1 class (also called the Lake-type) was a class of two submarines or U-boats built for and operated by the Austro-Hungarian Navy (). The class comprised and . The boats were built to an American design at the Pola Navy Yard after domestic design proposals failed to impress the Navy. Constructed between 1907 and 1909, the class was a part of the Austro-Hungarian Navy's efforts to competitively evaluate three foreign submarine designs.
Both U-1-class submarines were launched in 1909. An experimental design, the submarines included unique features such as a diving chamber and wheels for traveling along the seabed. Extensive sea trials were conducted in 1909 and 1910 to test these features as well as other components of the boats, including the diving tanks and engines for each boat. Safety and efficiency problems related to the gasoline engines of both submarines led the Navy to purchase new propulsion systems prior to World War I. The design of the U-1 class has been described by naval historians as a failure, obsolete by the time both submarines were commissioned into the Austro-Hungarian Navy in 1911. Nonetheless, tests of the design provided information that the Navy used to construct subsequent submarines. Both submarines of the U-1 class served as training boats through 1914, though they were mobilized briefly during the Balkan Wars.
At the outbreak of World War I, the U-1-class submarines were in drydock in Pola awaiting the installation of diesel engines. From 1915 to 1918, both boats conducted reconnaissance cruises out of Trieste and Pola, though neither sank any enemy vessels during the war. Declared obsolete in January 1918, both submarines were relegated to secondary duties and served as training boats at the Austro-Hungarian submarine base on Brioni Island, before being transferred back to Pola at the end of the war. When facing defeat in October 1918, the Austro-Hungarian government transferred its navy to the newly formed State of Slovenes, Croats and Serbs to avoid having to hand its ships over to the Allied Powers. Following the Armistice of Villa Giusti in November 1918, the U-1-class submarines were seized by Italian forces and subsequently granted to the Kingdom of Italy under the Treaty of Saint-Germain-en-Laye in 1920. Italy scrapped the submarines at Pola later that year.
Background With the establishment of the Austrian Naval League in September 1904 and the appointment of Vice-Admiral Rudolf Montecuccoli to the posts of Commander-in-Chief of the Navy (German: Marinekommandant) and Chief of the Naval Section of the War Ministry (German: Chef der Marinesektion) the following month, the Austro-Hungarian Navy began an expansion program befitting a great power. Montecuccoli immediately pursued the efforts championed by his predecessor, Admiral Hermann von Spaun, and pushed for a greatly expanded and modernized navy.
Montecuccoli's appointment as Marinekommandant coincided with the first efforts to develop submarines for Austria-Hungary. Prior to 1904, the Austro-Hungarian Navy had shown little to no interest in submarines. In early 1904, after allowing the navies of other countries to pioneer submarine developments, Constructor General (German: Generalschiffbauingenieur) of the Austro-Hungarian Navy, Siegfried Popper, ordered the Naval Technical Committee (German: Marinetechnisches Kommittee, MTK) to produce a submarine design. Popper himself submitted his first design for a submarine shortly before Montecuccoli took office; technical problems encountered during the initial design phase delayed further proposals from MTK for nearly a year. By this time, Montecuccoli had begun to outline his plans for the future of the Austro-Hungarian Navy.
Shortly after assuming command as Commander-in-Chief of the Navy, Montecuccoli drafted his first proposal for a modern Austrian fleet in early 1905. It was to consist of 12 battleships, 4 armored cruisers, 8 scout cruisers, 18 destroyers, 36 high seas torpedo craft, and 6 submarines. While far more attention at the time was being placed upon the construction of battleships—particularly dreadnoughts—Montecuccoli remained interested in the development of a submarine fleet for the Austro-Hungarian Navy and encouraged further development of the program.
Proposals Following up on Montecuccoli's initial naval expansion plan, MTK submitted its specifications for a class of submarines on 17 January 1905. The MTK design called for a single-hull boat with a waterline length of , a beam of and a draft of . The submarines were intended to displace when surfaced.
The Naval Section of the War Ministry (German: Marinesektion) remained skeptical about the seaworthiness of this design. Further proposals submitted by the public as part of a design competition were all rejected by the Navy as impractical. As a result, the Navy decided to purchase designs from three different foreign firms for a class of submarines. Each design was to be accompanied by two submarines to test each boat against the others. This was done to properly evaluate the various different proposals which would come forward.
Simon Lake, Germaniawerft, and John Philip Holland were each chosen by the Navy to produce a class of submarines for this competitive evaluation. The two Lake-designed submarines comprised the U-1 class, the Germaniawerft design became the , and the Holland design became the . In 1906, the Navy formally ordered plans for the building of two boats—designated U-1 and U-2—from the Lake Torpedo Boat Company of Bridgeport, Connecticut. The Austro-Hungarian Navy had contacted Lake Torpedo Boat Company as early as 1904 for a submarine design, but the decision to scrap the MTK proposal and initiate a competition among foreign builders led the Navy to formally solicit a bid from the American company. In 1906, Lake traveled to Austria-Hungary to negotiate the details of the agreement and on 24 November, he signed the contracts with the Navy in Pola to construct the U-1-class submarines.
Popper, in particular, had high praise for Lake's designs, telling the American naval architect, "When I saw your plans I recognized that you had introduced valuable features that were better than mine, and also that you had actual experience building and operating submarines, so I went to the Emperor and asked his consent to substitute your type of boat for my own...Do you know, Mr. Lake, I have been responsible for the design of all other vessels built for the Austrian Navy during the [past] 25 years?"
Designs
Although intended to serve as an experimental design when initially ordered, the U-1 class became the first submarines of the Austro-Hungarian Navy. The boats proved to be a disappointment. The naval historians David Dickson, Vincent O'Hara, and Richard Worth described the U-1 class as "obsolete and unreliable when completed and suffered from problems even after modifications". René Greger, another naval historian, wrote that "the type proved a total failure".
Despite these criticisms and shortcomings, the experimental nature of the submarines provided valuable information for the Austro-Hungarian Navy, and Lake's designs addressed what the Navy was asking for when ordering the submarine class. John Poluhowich writes in his book Argonaut: The Submarine Legacy of Simon Lake that "the two submarines were completed to the satisfaction of Austrian officials".
Their design was initially in line with Austro-Hungarian naval policy, which stressed coastal defense and patrolling of the Adriatic Sea. Following the onset of World War I, it became clear that Austro-Hungarian U-boats needed to be capable of offensive operations, namely raiding enemy shipping in the Adriatic and Mediterranean Seas.
General characteristics
The U-1-class submarines had an overall length of , a beam of , and a draught of at deep load. They were designed to displace surfaced, but when submerged they displaced . The boats were also built with a double hull, as opposed to the single-hull design initially proposed by the MTK. After their modernization, the length of the boats was increased to .
Derived from an earlier concept for a submarine intended for peaceful exploring of the sea, the U-1-class design had several features typical of Lake's designs. These including a diving chamber under the bow and two variable pitch propellers. The diving chamber was intended for manned underwater missions such as destroying ships with explosives and severing offshore telegraph cables, as well as for exiting or entering the submarine during an emergency. This diving chamber proved its usefulness during the sea trials of the U-1 class when the crew of one submarine forgot to bring their lunches on board before conducting an underwater endurance test. A diver from shore was able to transport lunch for the crew without the submarine having to resurface. Lake's design also called for two retractable wheels that, in theory, could allow travel over the seabed. The design also placed the diving tanks above the waterline of the cylindrical hull, which necessitated a heavy ballast keel for vertical stability and required flooding to be done by pumps.
The propulsion system for the U-1 class consisted of two gasoline engines for surface running and two electric motors for running submerged. The gasoline engines could produce , while the electric motors had an output of . These engines could produce a speed of while surfaced, and when submerged. The boats had an operational range of while traveling at when surfaced, and while traveling at when submerged. For underwater steering, the design of the U-1 class featured four pairs of diving planes. These planes provided the submarines with a considerable amount of maneuverability.
Both submarines had three torpedo tubes—two in the bow, one in the stern—and could carry up to five torpedoes, but typically carried three. While no deck guns were initially installed on the U-1 class, in 1917 a gun was mounted on the deck of both boats. These guns were removed in January 1918 when the boats were declared obsolete and returned to training duties. The boats were designed for a crew of 17 officers and men.
Boats Name Builder Laid down Launched Commissioned Vessels sunk or captured Tonnage sunk or captured FatePola Navy Yard, Pola2 July 190710 February 190915 April 1911 – –Ceded to Italy in 1920, scrapped18 July 19073 April 190922 June 1911
Construction and commissioning
U-1 was laid down on 2 July 1907 at the Pola Navy Yard (German:Seearsenal) at Pola. She was followed by U-2 on 18 July. Construction on the boats was delayed by the need to import the American-made engines for both submarines. U-1 was the first boat launched on 10 February 1908, and U-2 was launched on 3 April 1909.