List of Austrian U-boats
Encyclopedia
The Austro-Hungarian U-boat
fleet during the First World War mainly consisted of German manufactured units transported by rail from Germany's northern shipyards to the Austrian ports on the Adriatic Sea
. They served throughout the war against Italian, French and British shipping in the Mediterranean Sea
with some success, losing eight of the twenty eight boats in service in return. Following the end of the war in 1918, all Austrian submarines were surrendered to the Entente
powers, who disposed of them individually. As both Austria
and Hungary
became landlocked
in the aftermath of the war, no Austrian or Hungarian submarines (or any other naval vessels) have been commissioned since.
In some sources Austro-Hungarian U-boats are referenced with Roman numerals
as a way to distinguish them from German U-boats with similar numbers, but the Austro-Hungarian Navy
itself used Arabic numerals
. There are gaps in the numbering for several reasons. One series of Austro-Hungarian U-boats under construction in Germany was sold and commissioned into the Imperial German Navy. In other cases, U-boats commissioned into the Imperial German Navy were temporarily assigned Austro-Hungarian numbers when they operated in the Mediterranean. One final reason, in the case of the unassigned U-13, was superstition.
This is a list of all U-boats commissioned into the Austro-Hungarian Navy. (Submarines on which construction was begun but which were not completed or commissioned during World War I
are not included.)
s or U-boats named U-1
and U-2
, which were built for and operated by the Austro-Hungarian Navy. The U-1-class boats were built to an American design at the navy yard in Pola
. The class was a part of the Austro-Hungarian Navy's efforts to competitively evaluate three foreign submarine designs.
The two U-1-class boats, both launched in 1909, were 100 feet (30.5 m) long and as built were each powered by two gasoline engines while surfaced, and two electric motor
s when submerged. Neither boat was operational at the beginning of World War I because both were in drydock awaiting replacement diesel engine
s for their problematic gasoline engines. Beginning in 1915, both boats conducted reconnaissance cruises out of either Trieste
or Pola until declared obsolete in early 1918. Both remained in service as a training boats at the submarine base on Brioni, but each was at Pola at the end of the war. They were ceded to Italy as war reparations
in 1920 and scrapped at Pola. Neither submarine sank any ships during the war.
and U-4
, and was also a part of the Austro-Hungarian Navy's efforts to competitively evaluate three foreign submarine designs. The U-3-class boats were designed and built by Germaniawerft
of Kiel
, Germany. During the evaluations conducted by the Navy, the U-3 design bested the U-1
(Lake) and U-5
(Holland) classes in reliability and provided the best living conditions. They did, however, have the worst diving abilities of the three designs, and produced excessive exhaust smoke.The results of the evaluation led the Austro-Hungarian Navy to order five new U-boats from Germaniawerft as the .
The two U-3-class boats, both launched in 1908, were just under 140 feet (42.7 m) long and were each powered by two kerosene
two-stroke engines while surfaced, and two electric motors when submerged. The U-3 class initially had diving problems that were alleviated after several modifications to fins and diving plane
s. Both boats of the class served in combat during World War I. , the lead boat
of the class, was sunk by gunfire in August 1915. was the longest-serving Austro-Hungarian submarine and sank over of ships, including the Italian armored cruiser Giuseppe Garibaldi
in July 1915. U-4 was handed over to France as a war reparation in 1920 and scrapped.
, U-6
, and U-12
, and was also a part of the efforts of Austro-Hungarian navy to competitively evaluate three foreign submarine designs. The design of the boats was based upon John Philip Holland
's submarine design and the boats featured a single, teardrop
-shaped hull
, which resembled the design of modern nuclear submarines. The class members were just over 105 feet (32 m) long and displaced
240 tonnes (264.6 ST) surfaced and 273 tonnes (300.9 ST) submerged. All were originally equipped with two bow torpedo tubes and could carry four torpedoes. The first two boats, U-5 and U-6, built specifically for the Austro-Hungarian Navy, were partially constructed in the United States
and completed at Whitehead & Co. at Fiume. The third was completely constructed by Whitehead's at Fiume and purchased by Austria-Hungary
to bolster their U-boat fleet after the outbreak of World War I.
All three boats had successes during World War I, between them, sinking five ships with a combined gross register tonnage
(GRT) of 22,391. In addition they captured seven ships as prize
s and damaged a French dreadnought
of . All three boats were sunk during the war, though U-5, the lead boat of the class, was raised and recommissioned after her sinking. After the war's end, U-5, the only surviving example of the class, was ceded to Italy as a war reparation and was broken up in 1920.
of five U-boats —U-10
, U-11
, U-15
, U-16
, and U-17
— of the Austro-Hungarian Navy during World War I. The class was similar to the German Type UB I submarine
of the German Imperial Navy . The boats were small coastal submarines that displaced 125.5 long tons (127.5 t) surfaced and 140.25 long tons (142.5 t) submerged. The first two boats delivered to Austria-Hungary had previously been commissioned
in February 1915 by the Kaiserliche Marine
, while the remaining three were commissioned by the Austro-Hungarian marine in April 1915.
The U-10 class as a whole did not have much wartime success, with three of the boats sinking either one or no ships. Only one boat, sank more than of enemy ships. Of the five submarines of the class, only was sunk during the war; the remaining four were delivered as war reparations and broken up by 1920.
of the Austro-Hungarian Navy during World War I. She was launched in 1912 as the French Curie (Q 87), but captured and rebuilt for service in the Austro-Hungarian Navy. At war's end, the submarine was returned to France and restored to her former name.
Curie was launched in July 1912 at Toulon
and completed in 1914. She measured just under 171 feet (52.1 m) long and displaced nearly 400 metric tons (393.7 LT) on the surface and just over 550 metric tons (541.3 LT) when submerged. At the outbreak of World War I in August 1914, Curie was assigned to duty in the Mediterranean. In mid-December, Curies commander conceived a plan to infiltrate the Austro-Hungarian Navy's main base at Pola, but during the 20 December attempt, the vessel became ensnared in harbor defenses. Two Austro-Hungarian ships sank Curie, killing three of her crew; the remainder were taken prisoner.
The Austro-Hungarian Navy, which had a small and largely obsolete U-boat fleet, immediately began salvage efforts and succeeded in raising the lightly damaged submarine in early February 1915. After a refit, the boat was commissioned as SM U-14 in June, but had little success early in her career. When her commander fell ill in October, he was replaced by Georg Ludwig von Trapp. U-14 was damaged by a depth charge
attack in February 1916, and underwent an extensive modernization through November. Resuming duty under von Trapp, U-14 sank her first ship in April 1917, but had her most successful patrol in August, when she sank five ships—including , reportedly the largest cargo ship
in the world—in a six-day span.
In January 1918, von Trapp was replaced as commander, but neither of his two successors were able to match his accomplishments. In all, U-14 sank 11 ships with a combined gross register tonnage of nearly 48,000 tons. Returned to France at the end of the war, she rejoined the French Navy in July 1919 under her former name of Curie. She was stricken in 1928 and scrapped in 1929.
, U-21
, U-22
, and U-23
. The class is sometimes referred to as the Havmanden class because it was based upon the design of the Royal Danish Navy
's 1911 Havmanden class submarines
, three of which were built in Fiume.
Even though the Havmanden-class design was largely obsolete by the beginning of the war, four boats were ordered by the Austro-Hungarian Navy in 1915, in part because construction could begin immediately. Political considerations caused the order to be split between Austrian and Hungarian firms, which contributed to construction problems and delays, keeping any of the boats from being operational until mid 1917.
The class boats were just over than 127 feet (38.7 m) long and were armed with two front torpedo tubes, a deck gun
, and a machine gun
. The engines for the boats were unreliable, which compounded handling problems with the design. The U-20 class did not claim any wartime successes, yet lost two of the boats—U-20 and U-23—to enemy action during the war. The remaining two were delivered as war reparations and broken up. The conning tower
from U-20, which was raised and salvaged in 1962, is on display in a military museum in Vienna
.
, U-28
, U-29
, U-30
, U-31
, U-32
, U-40
, and U-41
—based upon the German Type UB II
design of the German Imperial Navy and was constructed under license in Austria-Hungary.
After the Austro-Hungarian Navy had filled its most urgent needs for submarines after the outbreak of World War I, they selected the German Type UB II design for its next group of submarines in mid 1915. Orders for the first six boats were placed in October 1915 with the Austrian firm of Cantiere Navale Triestino
and the Hungarian firm of Ganz Danubius. Two more boats were ordered in 1916, bringing the class total to eight.
The boats were just over 121 feet (36.9 m) long and were armed with two bow torpedo tubes, a deck gun, and a machine gun. For propulsion they were equipped with twin diesel engine
s for surface running and twin electric motors for subsurface movement. Although the class was based on the German design, the Austro-Hungarian U-boats were heavier and slightly faster underwater, but less heavily armed than their German counterparts
All eight boats were commissioned into the Austro-Hungarian Navy between 1917 and 1918 and saw active service during the war. and were the most successful in terms of ships sunk and gross register tonnage sunk, respectively. Two boats sank only one ship each, and a third, , sank no ships. U-30 was also the only boat of the class to be lost during the war. The remaining seven were ceded to France and Italy as war reparations and six were scrapped by 1920; the seventh sank while being towed to Bizerta for scrapping.
The German Type UB II design incorporated improvements over Type UB I boats, the first coastal submarines of the German Imperial Navy. Among these were twin engines and shafts for more redundancy during operations, a higher top speed, and larger torpedo tubes with double the complement of torpedoes. As a result the UB II boats were nearly twice as heavy as their predecessor UB I boats.
Both boats of the class were selected for German service in the Mediterranean while under construction. They were shipped via rail to Pola, assembled, launched, and commissioned in the German Imperial Navy, where both enjoyed great success against Allied shipping. In June 1917, the boats were decommissioned, handed over to Austria-Hungary, and then commissioned into the Austro-Hungarian Navy in July. The B in the designation of both boats was dropped, but the submarines retained the same numbers, becoming U-43 and U-47 under the Austro-Hungarian flag. At the end of the war and were ceded to Italy and France, respectively, and had been scrapped by 1920.
The Type U 66 was a class of five U-boats operated by the German Imperial Navy during World War I. The class is alternately referred to as the U-66-class or the Type UD. The class was built by Germaniawerft of Kiel to their 506d design as the U-7-class for the Austro-Hungarian Navy. The five boats were sold to the Imperial Germany Navy at the beginning of World War I when it was thought impossible for the submarines to reach the Mediterranean for delivery to Austria-Hungary. The Austro-Hungarian Navy, after competitively evaluating six submarines of three foreign designs, selected the Germaniwerft 506d or Type UD design over a design from Whitehead & Co. for the U-7 class. The boats, numbered U-7 to U-11, were designed to be 228 feet (69.5 m) long and displace between 695 & when surfaced and submerged. They were to be armed with five torpedo tubes and a deck gun. For propulsion the design called for twin diesel engines for surface running and twin electric motors for subsurface movement. The Austro-Hungarian Navy ordered the boats in February 1913 and construction began on the first boats in November. After the outbreak of World War I in August 1914, the Austro-Hungarian Navy became convinced that delivery of the still-unfinished submarines to the Mediterranean via Gibraltar would be impossible. As a result, they sold the five boats to the Imperial German Navy in November 1914. The German Navy assigned the numbers U-66 to U-70 to the five submarines and had them redesigned and reconstructed to their specifications. These changes, which included a larger deck gun, increased the displacement of the U-boats by almost 100 tonnes (110.2 ST) surfaced and nearly 50 tonnes (55.1 ST) submerged.
The U-48 class was a class of four U-boats planned for the Austro-Hungarian Navy during World War I. The design of the boats was based on plans purchased from the German firm of AG Weser
in January 1916. The Navy authorized Cantiere Navale Triestino to begin construction of the submarines in Pola in September 1916. Only two of the planned four boats were laid down, but both of them were never launched or completed. Both incomplete submarines were scrapped after the war ended.
The U-50 class was a class of four ocean-going U-boats planned for the Austro-Hungarian Navy during World War I. The design of the boats was based on the Project 835 design purchased from the German firm of Germaniawerft in July 1915. The Navy authorized Ganz Danubius to begin construction of the submarines in Fiume in February 1916. Only two of the planned four boats were laid down, but neither were ever launched or completed. The two incomplete submarines were scrapped
after the war ended.
The U-52 class was a class of four ocean-going U-boats planned for the Austro-Hungarian Navy during World War I. The submarine design was based on the A 6 proposal submitted by Stabilimento Tecnico Triestino
(STT) as part of a Navy design competition. STT, under its wartime name of Austriawerft, began construction on the first two boats in 1916, but neither boat was launched or completed before the end of the war. Both incomplete submarines were scrapped after the war ended. Neither of the third and fourth submarines was ever laid down.
The U-101 class was a class of nine U-boats planned for the Austro-Hungarian Navy during World War I. The class was based on the Type 1916 S 1 design from Ungarische Unterseebotsbau AG. The first three boats were laid down in late 1917 and early 1918 by Austriawerft in Trieste
, but none were launched or completed before the end of the war. None of the other six submarines was ever laid down.
The U-107 class was a class of U-boats planned for the Austro-Hungarian Navy during World War I. The design was similar to the Germaniawerft UD design which had formed the basis for the Austro-Hungarian Navy's s. Two boats (U-107 and U-108) were laid down in early 1918 by Ganz Danubius in Fiume, but neither was launched or completed before the end of the war. No other submarines of the class were ever laid down.
U-boat
U-boat is the anglicized version of the German word U-Boot , itself an abbreviation of Unterseeboot , and refers to military submarines operated by Germany, particularly in World War I and World War II...
fleet during the First World War mainly consisted of German manufactured units transported by rail from Germany's northern shipyards to the Austrian ports on the Adriatic Sea
Adriatic Sea
The Adriatic Sea is a body of water separating the Italian Peninsula from the Balkan peninsula, and the system of the Apennine Mountains from that of the Dinaric Alps and adjacent ranges...
. They served throughout the war against Italian, French and British shipping in the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
with some success, losing eight of the twenty eight boats in service in return. Following the end of the war in 1918, all Austrian submarines were surrendered to the Entente
Triple Entente
The Triple Entente was the name given to the alliance among Britain, France and Russia after the signing of the Anglo-Russian Entente in 1907....
powers, who disposed of them individually. As both Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
and Hungary
Hungary
Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...
became landlocked
Landlocked
A landlocked country is a country entirely enclosed by land, or whose only coastlines lie on closed seas. There are 48 landlocked countries in the world, including partially recognized states...
in the aftermath of the war, no Austrian or Hungarian submarines (or any other naval vessels) have been commissioned since.
In some sources Austro-Hungarian U-boats are referenced with Roman numerals
Roman numerals
The numeral system of ancient Rome, or Roman numerals, uses combinations of letters from the Latin alphabet to signify values. The numbers 1 to 10 can be expressed in Roman numerals as:...
as a way to distinguish them from German U-boats with similar numbers, but the Austro-Hungarian Navy
Austro-Hungarian Navy
The Austro-Hungarian Navy was the naval force of Austria-Hungary. Its official name in German was Kaiserliche und Königliche Kriegsmarine , abbreviated as k.u.k. Kriegsmarine....
itself used Arabic numerals
Arabic numerals
Arabic numerals or Hindu numerals or Hindu-Arabic numerals or Indo-Arabic numerals are the ten digits . They are descended from the Hindu-Arabic numeral system developed by Indian mathematicians, in which a sequence of digits such as "975" is read as a numeral...
. There are gaps in the numbering for several reasons. One series of Austro-Hungarian U-boats under construction in Germany was sold and commissioned into the Imperial German Navy. In other cases, U-boats commissioned into the Imperial German Navy were temporarily assigned Austro-Hungarian numbers when they operated in the Mediterranean. One final reason, in the case of the unassigned U-13, was superstition.
This is a list of all U-boats commissioned into the Austro-Hungarian Navy. (Submarines on which construction was begun but which were not completed or commissioned during World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
are not included.)
U-1 class
The U-1 class consisted of two submarineSubmarine
A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
s or U-boats named U-1
SM U-1 (Austria-Hungary)
SM U-1 or U-I was the lead boat of her class of submarine or U-boat built for and operated by the Austro-Hungarian Navy . U-1 was designed by American Simon Lake's Lake Torpedo Boat Company and built at the navy yard in Pola...
and U-2
SM U-2 (Austria-Hungary)
SM U-2 or U-II was a U-1-class submarine or U-boat built for and operated by the Austro-Hungarian Navy . U-2 was designed by American Simon Lake's Lake Torpedo Boat Company and built at the navy yard in Pola...
, which were built for and operated by the Austro-Hungarian Navy. The U-1-class boats were built to an American design at the navy yard in Pola
Pula
Pula is the largest city in Istria County, Croatia, situated at the southern tip of the Istria peninsula, with a population of 62,080 .Like the rest of the region, it is known for its mild climate, smooth sea, and unspoiled nature. The city has a long tradition of winemaking, fishing,...
. The class was a part of the Austro-Hungarian Navy's efforts to competitively evaluate three foreign submarine designs.
The two U-1-class boats, both launched in 1909, were 100 feet (30.5 m) long and as built were each powered by two gasoline engines while surfaced, and two electric motor
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...
s when submerged. Neither boat was operational at the beginning of World War I because both were in drydock awaiting replacement diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
s for their problematic gasoline engines. Beginning in 1915, both boats conducted reconnaissance cruises out of either Trieste
Trieste
Trieste is a city and seaport in northeastern Italy. It is situated towards the end of a narrow strip of land lying between the Adriatic Sea and Italy's border with Slovenia, which lies almost immediately south and east of the city...
or Pola until declared obsolete in early 1918. Both remained in service as a training boats at the submarine base on Brioni, but each was at Pola at the end of the war. They were ceded to Italy as war reparations
War reparations
War reparations are payments intended to cover damage or injury during a war. Generally, the term war reparations refers to money or goods changing hands, rather than such property transfers as the annexation of land.- History :...
in 1920 and scrapped at Pola. Neither submarine sank any ships during the war.
U-3 class
The U-3 class consisted of two U-boats, U-3SM U-3 (Austria-Hungary)
SM U-3 or U-III was the lead boat of the U-3 class of submarines or U-boats built for and operated by the Austro-Hungarian Navy before and during the First World War...
and U-4
SM U-4 (Austria-Hungary)
SM U-4 or U-IV was a U-3-class submarine or U-boat built for and operated by the Austro-Hungarian Navy before and during the First World War...
, and was also a part of the Austro-Hungarian Navy's efforts to competitively evaluate three foreign submarine designs. The U-3-class boats were designed and built by Germaniawerft
Friedrich Krupp Germaniawerft
Friedrich Krupp Germaniawerft was a German shipbuilding company, located in the harbour at Kiel, and one of the largest and most important builders of U-boats for the Kaiserliche Marine in World War I and the Kriegsmarine in World War II.-History:The company was founded in 1867 by Lloyd Foster, as...
of Kiel
Kiel
Kiel is the capital and most populous city in the northern German state of Schleswig-Holstein, with a population of 238,049 .Kiel is approximately north of Hamburg. Due to its geographic location in the north of Germany, the southeast of the Jutland peninsula, and the southwestern shore of the...
, Germany. During the evaluations conducted by the Navy, the U-3 design bested the U-1
U-1 class submarine (Austria-Hungary)
The U-1 class was a class of two submarines or U-boats built for and operated by the Austro-Hungarian Navy . The U-1-class boats were built to an American design at the navy yard in Pola...
(Lake) and U-5
U-5 class submarine (Austria-Hungary)
The U-5 class was a class of three submarines or U-boats that were operated by the Austro-Hungarian Navy before and during World War I. The class was a part of the Austro-Hungarian Navy's efforts to competitively evaluate three foreign submarine designs....
(Holland) classes in reliability and provided the best living conditions. They did, however, have the worst diving abilities of the three designs, and produced excessive exhaust smoke.The results of the evaluation led the Austro-Hungarian Navy to order five new U-boats from Germaniawerft as the .
The two U-3-class boats, both launched in 1908, were just under 140 feet (42.7 m) long and were each powered by two kerosene
Kerosene
Kerosene, sometimes spelled kerosine in scientific and industrial usage, also known as paraffin or paraffin oil in the United Kingdom, Hong Kong, Ireland and South Africa, is a combustible hydrocarbon liquid. The name is derived from Greek keros...
two-stroke engines while surfaced, and two electric motors when submerged. The U-3 class initially had diving problems that were alleviated after several modifications to fins and diving plane
Diving plane
A diving plane, also known as a hydroplane, is a control surface found on submarines which allow the vessel to pitch its bow and stern up or down to assist in the process of submerging or surfacing the boat, as well as controlling depth when submerged....
s. Both boats of the class served in combat during World War I. , the lead boat
Lead ship
The lead ship or class leader is the first of a series or class of ships all constructed according to the same general design. The term is applicable military ships and larger civilian craft.-Overview:...
of the class, was sunk by gunfire in August 1915. was the longest-serving Austro-Hungarian submarine and sank over of ships, including the Italian armored cruiser Giuseppe Garibaldi
Italian cruiser Giuseppe Garibaldi (1899)
Giuseppe Garibaldi was the lead ship of her class of armoured cruisers for Italy's Regia Marina. The ship was launched on 29 June 1899 and served the Regia Marina until she was sunk by torpedoes from Austro-Hungarian Navy submarine on 18 July 1915, with loss of 57 lives.Garibaldis wreck is located...
in July 1915. U-4 was handed over to France as a war reparation in 1920 and scrapped.
U-5 class
The U-5 class consisted of three U-boats, U-5SM U-5 (Austria-Hungary)
SM U-5 or U-V was the lead boat of the U-5 class of submarines or U-boats built for and operated by the Austro-Hungarian Navy before and during the First World War. The submarine was built as part of a plan to evaluate foreign submarine designs, and was the first of three boats of the class built...
, U-6
SM U-6 (Austria-Hungary)
SM U-6 or U-VI was a U-5-class submarine or U-boat built for and operated by the Austro-Hungarian Navy before and during the First World War. The submarine was built as part of a plan to evaluate foreign submarine designs, and was the second of three boats of the class built by Whitehead & Co...
, and U-12
SM U-12 (Austria-Hungary)
SM U-12 or U-XII was a U-5-class submarine or U-boat built for and operated by the Austro-Hungarian Navy before and during the First World War.- Introduction :Built on speculation by Whitehead & Co...
, and was also a part of the efforts of Austro-Hungarian navy to competitively evaluate three foreign submarine designs. The design of the boats was based upon John Philip Holland
John Philip Holland
John Philip Holland was an Irish engineer who developed the first submarine to be formally commissioned by the U.S...
's submarine design and the boats featured a single, teardrop
Teardrop hull
A teardrop hull is a submarine hull design which emphasizes hydrodynamic flow above all other factors. Benefits over previous types include increased underwater speed and a smaller acoustic signature, making detection by sonar more difficult...
-shaped hull
Hull (watercraft)
A hull is the watertight body of a ship or boat. Above the hull is the superstructure and/or deckhouse, where present. The line where the hull meets the water surface is called the waterline.The structure of the hull varies depending on the vessel type...
, which resembled the design of modern nuclear submarines. The class members were just over 105 feet (32 m) long and displaced
Displacement (ship)
A ship's displacement is its weight at any given time, generally expressed in metric tons or long tons. The term is often used to mean the ship's weight when it is loaded to its maximum capacity. A number of synonymous terms exist for this maximum weight, such as loaded displacement, full load...
240 tonnes (264.6 ST) surfaced and 273 tonnes (300.9 ST) submerged. All were originally equipped with two bow torpedo tubes and could carry four torpedoes. The first two boats, U-5 and U-6, built specifically for the Austro-Hungarian Navy, were partially constructed in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and completed at Whitehead & Co. at Fiume. The third was completely constructed by Whitehead's at Fiume and purchased by Austria-Hungary
Austria-Hungary
Austria-Hungary , more formally known as the Kingdoms and Lands Represented in the Imperial Council and the Lands of the Holy Hungarian Crown of Saint Stephen, was a constitutional monarchic union between the crowns of the Austrian Empire and the Kingdom of Hungary in...
to bolster their U-boat fleet after the outbreak of World War I.
All three boats had successes during World War I, between them, sinking five ships with a combined gross register tonnage
Gross Register Tonnage
Gross register tonnage a ship's total internal volume expressed in "register tons", one of which equals to a volume of . It is calculated from the total permanently enclosed capacity of the vessel. The ship's net register tonnage is obtained by reducing the volume of non-revenue-earning spaces i.e...
(GRT) of 22,391. In addition they captured seven ships as prize
Prize (law)
Prize is a term used in admiralty law to refer to equipment, vehicles, vessels, and cargo captured during armed conflict. The most common use of prize in this sense is the capture of an enemy ship and its cargo as a prize of war. In the past, it was common that the capturing force would be allotted...
s and damaged a French dreadnought
Dreadnought
The dreadnought was the predominant type of 20th-century battleship. The first of the kind, the Royal Navy's had such an impact when launched in 1906 that similar battleships built after her were referred to as "dreadnoughts", and earlier battleships became known as pre-dreadnoughts...
of . All three boats were sunk during the war, though U-5, the lead boat of the class, was raised and recommissioned after her sinking. After the war's end, U-5, the only surviving example of the class, was ceded to Italy as a war reparation and was broken up in 1920.
U-10 class
The U-10 class was a classShip class
A ship class is a group of ships of a similar design. This is distinct from a ship-type, which might reflect a similarity of tonnage or intended use. For example, the is a nuclear aircraft carrier of the Nimitz class....
of five U-boats —U-10
SM U-10 (Austria-Hungary)
SM U-10 or U-X was the lead boat of the U-10 class of submarines for the Austro-Hungarian Navy during World War I. She was originally a German Type UB I submarine commissioned into the German Imperial Navy as SM UB-1....
, U-11
SM U-11 (Austria-Hungary)
SM U-11 or U-XI was a in the Austro-Hungarian Navy during World War I. She was originally a German Type UB I submarine commissioned into the German Imperial Navy as SM UB-15....
, U-15
SM U-15 (Austria-Hungary)
SM U-15 or U-XV was a or U-boat of the Austro-Hungarian Navy during World War I. U-15 was constructed in Germany and shipped by rail to Pola where she was assembled and launched in April 1915. She was commissioned in October 1915. U-15 was the most successful boat of the U-10 class, sinking six...
, U-16
SM U-16 (Austria-Hungary)
SM U-16 or U-XVI was a or U-boat of the Austro-Hungarian Navy during World War I. U-16 was constructed in Germany and shipped by rail to Pula where she was assembled and completed in September 1915. She was commissioned in October 1915....
, and U-17
SM U-17 (Austria-Hungary)
SM U-17 or U-XVII was a or U-boat of the Austro-Hungarian Navy during World War I. U-17 was laid down in Germany in April 1915 and shipped in sections by rail to Pola in August, where she was assembled...
— of the Austro-Hungarian Navy during World War I. The class was similar to the German Type UB I submarine
German type UB I submarine
The Type UB I was a class of small coastal submarines built in Germany at the beginning of the First World War. Twenty boats were constructed, most of which went into service with the German Imperial Navy. Boats of this design were also operated by the Austro-Hungarian Navy and the Bulgarian...
of the German Imperial Navy . The boats were small coastal submarines that displaced 125.5 long tons (127.5 t) surfaced and 140.25 long tons (142.5 t) submerged. The first two boats delivered to Austria-Hungary had previously been commissioned
Ship commissioning
Ship commissioning is the act or ceremony of placing a ship in active service, and may be regarded as a particular application of the general concepts and practices of project commissioning. The term is most commonly applied to the placing of a warship in active duty with its country's military...
in February 1915 by the Kaiserliche Marine
Kaiserliche Marine
The Imperial German Navy was the German Navy created at the time of the formation of the German Empire. It existed between 1871 and 1919, growing out of the small Prussian Navy and Norddeutsche Bundesmarine, which primarily had the mission of coastal defense. Kaiser Wilhelm II greatly expanded...
, while the remaining three were commissioned by the Austro-Hungarian marine in April 1915.
The U-10 class as a whole did not have much wartime success, with three of the boats sinking either one or no ships. Only one boat, sank more than of enemy ships. Of the five submarines of the class, only was sunk during the war; the remaining four were delivered as war reparations and broken up by 1920.
U-14 class
SM U-14 or U-XIV was a U-boatU-boat
U-boat is the anglicized version of the German word U-Boot , itself an abbreviation of Unterseeboot , and refers to military submarines operated by Germany, particularly in World War I and World War II...
of the Austro-Hungarian Navy during World War I. She was launched in 1912 as the French Curie (Q 87), but captured and rebuilt for service in the Austro-Hungarian Navy. At war's end, the submarine was returned to France and restored to her former name.
Curie was launched in July 1912 at Toulon
Toulon
Toulon is a town in southern France and a large military harbor on the Mediterranean coast, with a major French naval base. Located in the Provence-Alpes-Côte-d'Azur region, Toulon is the capital of the Var department in the former province of Provence....
and completed in 1914. She measured just under 171 feet (52.1 m) long and displaced nearly 400 metric tons (393.7 LT) on the surface and just over 550 metric tons (541.3 LT) when submerged. At the outbreak of World War I in August 1914, Curie was assigned to duty in the Mediterranean. In mid-December, Curies commander conceived a plan to infiltrate the Austro-Hungarian Navy's main base at Pola, but during the 20 December attempt, the vessel became ensnared in harbor defenses. Two Austro-Hungarian ships sank Curie, killing three of her crew; the remainder were taken prisoner.
The Austro-Hungarian Navy, which had a small and largely obsolete U-boat fleet, immediately began salvage efforts and succeeded in raising the lightly damaged submarine in early February 1915. After a refit, the boat was commissioned as SM U-14 in June, but had little success early in her career. When her commander fell ill in October, he was replaced by Georg Ludwig von Trapp. U-14 was damaged by a depth charge
Depth charge
A depth charge is an anti-submarine warfare weapon intended to destroy or cripple a target submarine by the shock of exploding near it. Most use explosives and a fuze set to go off at a preselected depth in the ocean. Depth charges can be dropped by either surface ships, patrol aircraft, or from...
attack in February 1916, and underwent an extensive modernization through November. Resuming duty under von Trapp, U-14 sank her first ship in April 1917, but had her most successful patrol in August, when she sank five ships—including , reportedly the largest cargo ship
Cargo ship
A cargo ship or freighter is any sort of ship or vessel that carries cargo, goods, and materials from one port to another. Thousands of cargo carriers ply the world's seas and oceans each year; they handle the bulk of international trade...
in the world—in a six-day span.
In January 1918, von Trapp was replaced as commander, but neither of his two successors were able to match his accomplishments. In all, U-14 sank 11 ships with a combined gross register tonnage of nearly 48,000 tons. Returned to France at the end of the war, she rejoined the French Navy in July 1919 under her former name of Curie. She was stricken in 1928 and scrapped in 1929.
U-20 class
The U-20 class was a class of four U-boats, U-20SM U-20 (Austria-Hungary)
SM U-20 or U-XX was the lead boat of the of submarines or U-boats built for and operated by the Austro-Hungarian Navy during the First World War...
, U-21
SM U-21 (Austria-Hungary)
SM U-21 or U-XXI was a or U-boat built for and operated by the Austro-Hungarian Navy during the First World War. The design for U-21 was based on submarines of the Royal Danish Navy's Havmanden class , and was largely obsolete by the beginning of the war.U-21 was just over long and was armed...
, U-22
SM U-22 (Austria-Hungary)
SM U-22 or U-XXII was a or U-boat built for and operated by the Austro-Hungarian Navy during the First World War. The design for U-22 was based on submarines of the Royal Danish Navy's Havmanden class , and was largely obsolete by the beginning of the war.U-22 was just over long and was armed...
, and U-23
SM U-23 (Austria-Hungary)
SM U-23 or U-XXIII was a or U-boat built for and operated by the Austro-Hungarian Navy during the First World War. The design for U-23 was based on submarines of the Royal Danish Navy's Havmanden class , and was largely obsolete by the beginning of the war.U-23 was just over long and was armed...
. The class is sometimes referred to as the Havmanden class because it was based upon the design of the Royal Danish Navy
Royal Danish Navy
The Royal Danish Navy is the sea-based branch of the Danish Defence force. The RDN is mainly responsible for maritime defence and maintaining the sovereignty of Danish, Greenlandic and Faroese territorial waters...
's 1911 Havmanden class submarines
Havmanden class submarine (1911)
The Havmanden class was a class of six submarines built for the Royal Danish Navy from 1911 to 1914. Also later known as the A class, the boats were designed by the Austro-Hungarian firm Whitehead & Co. of Fiume...
, three of which were built in Fiume.
Even though the Havmanden-class design was largely obsolete by the beginning of the war, four boats were ordered by the Austro-Hungarian Navy in 1915, in part because construction could begin immediately. Political considerations caused the order to be split between Austrian and Hungarian firms, which contributed to construction problems and delays, keeping any of the boats from being operational until mid 1917.
The class boats were just over than 127 feet (38.7 m) long and were armed with two front torpedo tubes, a deck gun
Deck gun
A deck gun is a type of artillery cannon mounted on the deck of a ship or submarine.The deck gun was used as a defensive weapon against smaller boats or ships and in certain cases where torpedo use was limited. Typically a crew of three; gunner, loader, and layer, operated the gun, while others...
, and a machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....
. The engines for the boats were unreliable, which compounded handling problems with the design. The U-20 class did not claim any wartime successes, yet lost two of the boats—U-20 and U-23—to enemy action during the war. The remaining two were delivered as war reparations and broken up. The conning tower
Conning tower
A conning tower is a raised platform on a ship or submarine, often armored, from which an officer can con the vessel; i.e., give directions to the helmsman. It is usually located as high on the ship as practical, to give the conning team good visibility....
from U-20, which was raised and salvaged in 1962, is on display in a military museum in Vienna
Vienna
Vienna is the capital and largest city of the Republic of Austria and one of the nine states of Austria. Vienna is Austria's primary city, with a population of about 1.723 million , and is by far the largest city in Austria, as well as its cultural, economic, and political centre...
.
U-27 class
The U-27 class was a class of eight U-boats —U-27SM U-27 (Austria-Hungary)
SM U-27 or U-XXVII was the lead boat of the U-27 class of U-boats or submarines for the Austro-Hungarian Navy. U-27 was built by the Austrian firm of Cantiere Navale Triestino at the Pola Navy Yard and launched on 19 October 1916. She was commissioned on 24 February 1917.She had a single hull and...
, U-28
SM U-28 (Austria-Hungary)
SM U-28 or U-XXVIII was a U-27 class U-boat or submarine for the Austro-Hungarian Navy. U-28, built by the Austrian firm of Cantiere Navale Triestino at the Pola Navy Yard, was launched in January 1917 and commissioned in June....
, U-29
SM U-29 (Austria-Hungary)
SM U-29 or U-XXIX was a U-27 class U-boat or submarine for the Austro-Hungarian Navy. U-29, built by the Hungarian firm of Ganz Danubius at Fiume, was launched in October 1916 and commissioned in January 1917....
, U-30
SM U-30 (Austria-Hungary)
SM U-30 or U-XXX was a U-27 class U-boat or submarine of the Austro-Hungarian Navy. U-30, built by the Hungarian firm of Ganz Danubius at Fiume, was launched in December 1916 and commissioned in February 1917....
, U-31
SM U-31 (Austria-Hungary)
SM U-31 or U-XXXI was a U-27 class U-boat or submarine for the Austro-Hungarian Navy. U-31, built by the Hungarian firm of Ganz Danubius at Fiume, was launched in March 1917 and commissioned in April....
, U-32
SM U-32 (Austria-Hungary)
SM U-32 or U-XXXII was a U-27 class U-boat or submarine for the Austro-Hungarian Navy. U-32, built by the Hungarian firm of Ganz Danubius at Fiume, was launched in May 1917 and commissioned in June....
, U-40
SM U-40 (Austria-Hungary)
SM U-40 or U-XL was a U-27 class U-boat or submarine for the Austro-Hungarian Navy. U-40, built by the Austrian firm of Cantiere Navale Triestino at the Pola Navy Yard, was launched in April 1917 and commissioned in August....
, and U-41
SM U-41 (Austria-Hungary)
SM U-41 or U-XLI was a U-27 class U-boat or submarine for the Austro-Hungarian Navy. U-41, built by the Austrian firm of Cantiere Navale Triestino at the Pola Navy Yard, was launched in November 1917. When she was commissioned in February 1918, she became the last boat of her class to enter service...
—based upon the German Type UB II
German type UB II submarine
The UB II type submarine was a class of U-boat built during World War I by the Kaiserliche Marine. They were enlarged from the preceding type UB I and were more effective vessels. The boats were a single hull design with a 50 metre maximum diving depth and a 30-45 second diving time...
design of the German Imperial Navy and was constructed under license in Austria-Hungary.
After the Austro-Hungarian Navy had filled its most urgent needs for submarines after the outbreak of World War I, they selected the German Type UB II design for its next group of submarines in mid 1915. Orders for the first six boats were placed in October 1915 with the Austrian firm of Cantiere Navale Triestino
Cantiere Navale Triestino
CANT was an Italian aviation company which originally specialised in building naval aircraft, formed in 1923 as part of the CNT...
and the Hungarian firm of Ganz Danubius. Two more boats were ordered in 1916, bringing the class total to eight.
The boats were just over 121 feet (36.9 m) long and were armed with two bow torpedo tubes, a deck gun, and a machine gun. For propulsion they were equipped with twin diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
s for surface running and twin electric motors for subsurface movement. Although the class was based on the German design, the Austro-Hungarian U-boats were heavier and slightly faster underwater, but less heavily armed than their German counterparts
All eight boats were commissioned into the Austro-Hungarian Navy between 1917 and 1918 and saw active service during the war. and were the most successful in terms of ships sunk and gross register tonnage sunk, respectively. Two boats sank only one ship each, and a third, , sank no ships. U-30 was also the only boat of the class to be lost during the war. The remaining seven were ceded to France and Italy as war reparations and six were scrapped by 1920; the seventh sank while being towed to Bizerta for scrapping.
U-43 class
The U-43 class was a class of two coastal U-boats which were Type UB II submarines —U-43, and U-47—of the Imperial German Navy, making the two classes identical. From the beginning of World War I, Austria-Hungary had been working to increase the size of its U-boat fleet, so the Imperial German Navy, which was finding it difficult to obtain trained submarine crews, sold two of its UB II boats, and , to its ally in June 1917.The German Type UB II design incorporated improvements over Type UB I boats, the first coastal submarines of the German Imperial Navy. Among these were twin engines and shafts for more redundancy during operations, a higher top speed, and larger torpedo tubes with double the complement of torpedoes. As a result the UB II boats were nearly twice as heavy as their predecessor UB I boats.
Both boats of the class were selected for German service in the Mediterranean while under construction. They were shipped via rail to Pola, assembled, launched, and commissioned in the German Imperial Navy, where both enjoyed great success against Allied shipping. In June 1917, the boats were decommissioned, handed over to Austria-Hungary, and then commissioned into the Austro-Hungarian Navy in July. The B in the designation of both boats was dropped, but the submarines retained the same numbers, becoming U-43 and U-47 under the Austro-Hungarian flag. At the end of the war and were ceded to Italy and France, respectively, and had been scrapped by 1920.
Other classes
Several other classes were designed, but none of these ended up being operated by the Austro-Hungarian navy.The Type U 66 was a class of five U-boats operated by the German Imperial Navy during World War I. The class is alternately referred to as the U-66-class or the Type UD. The class was built by Germaniawerft of Kiel to their 506d design as the U-7-class for the Austro-Hungarian Navy. The five boats were sold to the Imperial Germany Navy at the beginning of World War I when it was thought impossible for the submarines to reach the Mediterranean for delivery to Austria-Hungary. The Austro-Hungarian Navy, after competitively evaluating six submarines of three foreign designs, selected the Germaniwerft 506d or Type UD design over a design from Whitehead & Co. for the U-7 class. The boats, numbered U-7 to U-11, were designed to be 228 feet (69.5 m) long and displace between 695 & when surfaced and submerged. They were to be armed with five torpedo tubes and a deck gun. For propulsion the design called for twin diesel engines for surface running and twin electric motors for subsurface movement. The Austro-Hungarian Navy ordered the boats in February 1913 and construction began on the first boats in November. After the outbreak of World War I in August 1914, the Austro-Hungarian Navy became convinced that delivery of the still-unfinished submarines to the Mediterranean via Gibraltar would be impossible. As a result, they sold the five boats to the Imperial German Navy in November 1914. The German Navy assigned the numbers U-66 to U-70 to the five submarines and had them redesigned and reconstructed to their specifications. These changes, which included a larger deck gun, increased the displacement of the U-boats by almost 100 tonnes (110.2 ST) surfaced and nearly 50 tonnes (55.1 ST) submerged.
The U-48 class was a class of four U-boats planned for the Austro-Hungarian Navy during World War I. The design of the boats was based on plans purchased from the German firm of AG Weser
AG Weser
Aktien-Gesellschaft Weser was one of the great German shipbuilding companies, located at the Weser River in Bremen. Founded in 1873 it was finally closed in 1983. Altogether, AG Weser built about 1400 ships of different types, including many war ships...
in January 1916. The Navy authorized Cantiere Navale Triestino to begin construction of the submarines in Pola in September 1916. Only two of the planned four boats were laid down, but both of them were never launched or completed. Both incomplete submarines were scrapped after the war ended.
The U-50 class was a class of four ocean-going U-boats planned for the Austro-Hungarian Navy during World War I. The design of the boats was based on the Project 835 design purchased from the German firm of Germaniawerft in July 1915. The Navy authorized Ganz Danubius to begin construction of the submarines in Fiume in February 1916. Only two of the planned four boats were laid down, but neither were ever launched or completed. The two incomplete submarines were scrapped
Ship breaking
Ship breaking or ship demolition is a type of ship disposal involving the breaking up of ships for scrap recycling. Most ships have a lifespan of a few decades before there is so much wear that refitting and repair becomes uneconomical. Ship breaking allows materials from the ship, especially...
after the war ended.
The U-52 class was a class of four ocean-going U-boats planned for the Austro-Hungarian Navy during World War I. The submarine design was based on the A 6 proposal submitted by Stabilimento Tecnico Triestino
Stabilimento Tecnico Triestino
Stabilimento Tecnico Triestino was a private shipbuilding company based in Trieste from the mid-19th to early 20th century, and the most important naval shipbuilding firm of the Austro-Hungarian Empire....
(STT) as part of a Navy design competition. STT, under its wartime name of Austriawerft, began construction on the first two boats in 1916, but neither boat was launched or completed before the end of the war. Both incomplete submarines were scrapped after the war ended. Neither of the third and fourth submarines was ever laid down.
The U-101 class was a class of nine U-boats planned for the Austro-Hungarian Navy during World War I. The class was based on the Type 1916 S 1 design from Ungarische Unterseebotsbau AG. The first three boats were laid down in late 1917 and early 1918 by Austriawerft in Trieste
Trieste
Trieste is a city and seaport in northeastern Italy. It is situated towards the end of a narrow strip of land lying between the Adriatic Sea and Italy's border with Slovenia, which lies almost immediately south and east of the city...
, but none were launched or completed before the end of the war. None of the other six submarines was ever laid down.
The U-107 class was a class of U-boats planned for the Austro-Hungarian Navy during World War I. The design was similar to the Germaniawerft UD design which had formed the basis for the Austro-Hungarian Navy's s. Two boats (U-107 and U-108) were laid down in early 1918 by Ganz Danubius in Fiume, but neither was launched or completed before the end of the war. No other submarines of the class were ever laid down.