German Type XXIII submarines were the first so-called
elektroboot
An elektroboot ("electric boat" in German) was a submarine designed to operate entirely submerged, rather than as submersibles that could submerge as a temporary means to escape detection or launch an attack.
History
Even before the Second ...
e ("electric boats") to become operational. They were small
coastal submarine
A coastal submarine or littoral submarine is a small, maneuverable submarine with shallow draft well suited to navigation of coastal channels and harbors. Although size is not precisely defined, coastal submarines are larger than midget submarine ...
s designed to operate in the shallow waters of the
North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...
,
Black Sea
The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Roma ...
and
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ea ...
, where larger
Type XXI electric boats were at risk in
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
. They were so small they could carry only two
torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, su ...
es, which had to be loaded externally. As with their far larger sisters—the Type XXI—they were able to remain submerged almost all of the time and were faster than conventional U-boats, due to the improved streamlining of their shape, batteries with larger capacity and the
snorkel, which allowed the diesel engines to be used while submerged. The Type XXI and XXIII U-boats revolutionized post-war submarine design. Nearly a thousand Type XXIII boats were projected towards the close of World War II, but most of these were either cancelled, scrapped incomplete, or only projected.
Background
When development began on the Type XXI U-boat in late 1942, it was proposed to simultaneously develop a smaller version incorporating the same advanced technology to replace the
Type II coastal submarine.
Admiral Karl Dönitz added two requirements: as the boat would have to operate in the
Mediterranean
The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the e ...
and the
Black Sea
The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Roma ...
, it had to be able to be transported by rail, and it had to use the standard torpedo tubes.
The development of the Type XXIII was given a high priority, with an emphasis on using existing components as much as possible. To reduce development time,
Hellmuth Walter
Hellmuth Walter (26 August 1900 – 16 December 1980) was a German engineer who pioneered research into rocket engines and gas turbines. His most noteworthy contributions were rocket motors for the Messerschmitt Me 163 and Bachem Ba 349 intercept ...
designed the new submarine based on the previous
Type XXII prototype. By 30 June 1943 the design was ready and construction began in parallel at several shipyards in Germany, France, Italy and Ukraine. The lead contractor was
Deutsche Werft
Deutsche Werft (English: German Shipyard) was a shipbuilding company in Finkenwerder Rüschpark, Hamburg, Germany. It was founded in 1918 by Albert Ballin and with Gutehoffnungshütte (GHH), ''Allgemeine Elektricitäts-Gesellschaft'' (AEG) and ' ...
in
Hamburg
(male), (female) en, Hamburger(s),
Hamburgian(s)
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.
As with the Type XXI, the Type XXIII was intended to be constructed in sections, various modules being produced by different subcontractors. Some were to be assembled at foreign yards, including ''U-2446'' through ''U-2460'' at the Deutsche Werft yard at
Mykolaiv
Mykolaiv ( uk, Миколаїв, ) is a List of cities in Ukraine, city and List of hromadas of Ukraine, municipality in Southern Ukraine, the Administrative centre, administrative center of the Mykolaiv Oblast. Mykolaiv city, which provides U ...
, Southern Ukraine. These were reassigned to the
Linzner yard on 1 May 1944 and subsequently cancelled.
[Polmar, p. 322] In the end, circumstances meant that construction was concentrated at
Germaniawerft in
Kiel
Kiel () is the capital and most populous city in the northern Germany, German state of Schleswig-Holstein, with a population of 246,243 (2021).
Kiel lies approximately north of Hamburg. Due to its geographic location in the southeast of the J ...
and
Deutsche Werft
Deutsche Werft (English: German Shipyard) was a shipbuilding company in Finkenwerder Rüschpark, Hamburg, Germany. It was founded in 1918 by Albert Ballin and with Gutehoffnungshütte (GHH), ''Allgemeine Elektricitäts-Gesellschaft'' (AEG) and ' ...
in
Hamburg
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Hamburgian(s)
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, postal ...
, Germaniawerft building 51 and Deutsche Werft 49. Of the 280 submarines ordered, only 61 entered service, and only 6 ever carried out a war patrol.
Description
The Type XXIII had an all-welded single hull, the first submarine to use such a design. It had a fully streamlined outer casing and apart from the relatively small conning tower and a fairing which housed the Diesel exhaust silencer, it had an uncluttered upper deck. In line with Walter's design practice, there were no forward
hydroplanes, although these were added later.
The submarine was propelled by a single three-bladed propeller and steered by a single rudder. As with the Type XXI, the lower section of the figure-of-eight hull was used to house a large 62-cell battery.
In order to allow the boat to be transported by rail, the hull sections had to be limited in size to fit the standard
loading gauge
A loading gauge is a diagram or physical structure that defines the maximum height and width dimensions in railway vehicles and their loads. Their purpose is to ensure that rail vehicles can pass safely through tunnels and under bridges, and ke ...
. For transportation, the hull was broken into four sections and the bridge was removed. Due to the space restrictions, the forward bow section had to be made as short as possible, which meant that only two torpedo tubes could be fitted and no reload torpedoes could be carried. The torpedoes were loaded by ballasting the submarine down at the stern so that the bow lifted clear of the water and the torpedoes could be loaded directly into their tubes from a barge.
The Type XXIII proved to have excellent handling characteristics, and was highly maneuverable both on the surface and underwater. Its
crash dive
A crash dive is a maneuver by a submarine in which the vessel submerges as quickly as possible to avoid attack. Crash diving from the surface to avoid attack has been largely rendered obsolete with the advent of nuclear-powered submarines, as they ...
time was 9 seconds, and its maximum diving depth was . Submerged, its speed was , and while surfaced its speed was . A submerged speed of could be attained while snorkeling.
Construction
The first forty-nine boats (''U-2321'' to ''U-2331'', and ''U-2334'' to ''U-2371'') were ordered from Deutsche Werft, Hamburg, while two (''U-2332'' and ''U-2333'') were ordered from Friedrich Krupp
Germaniawerft's yard at Kiel. Twenty-nine further boats (''U-2372'' to ''U-2400'') were ordered from Deutsche Werft's wartime occupied yards at Toulon, but the first nine of these were scrapped incomplete on the stocks and the remainder never commenced.
Another sixty were ordered to be built by the company at other yards in occupied nations - thirty at
Genoa
Genoa ( ; it, Genova ; lij, Zêna ). is the capital of the Italian region of Liguria and the List of cities in Italy, sixth-largest city in Italy. In 2015, 594,733 people lived within the city's administrative limits. As of the 2011 Italian ce ...
(''U-2401'' to ''U-2430''), fifteen at
Monfalcone
Monfalcone (; Bisiacco: ; fur, Monfalcon; sl, Tržič; archaic german: Falkenberg) is a town and ''comune'' of the province of Gorizia in Friuli Venezia Giulia, northern Italy, located on the Gulf of Trieste. Monfalcone means 'falcon mountain' ...
(''U-2431'' to ''U-2445'') and another fifteen at
Mykolaiv
Mykolaiv ( uk, Миколаїв, ) is a List of cities in Ukraine, city and List of hromadas of Ukraine, municipality in Southern Ukraine, the Administrative centre, administrative center of the Mykolaiv Oblast. Mykolaiv city, which provides U ...
and
Linz
Linz ( , ; cs, Linec) is the capital of Upper Austria and third-largest city in Austria. In the north of the country, it is on the Danube south of the Czech border. In 2018, the population was 204,846.
In 2009, it was a European Capital of ...
(''U-2446'' to ''U-2460''), where a further forty (''U-2461'' to ''U-2500'') were projected but never ordered. All of these were cancelled and never commenced.
Eight hundred additional units were intended to be built by Deutsche Werft - five hundred at Hamburg (''U-4001'' to ''U-4500''), of which the first 120 were ordered and started were subsequently scrapped incomplete, with the others cancelled and never begun; and three hundred at Kiel (''U-4701'' to ''U-5000''), where eleven (''U-4701'' to ''U-4712'' , exclude ''U-4708'') were actually built (orders for ''U-4713'' to ''U-4891'' were cancelled, while ''U-4892'' to ''U-5000'' were projected only).
The first Type XXIII, , was launched from
Deutsche Werft
Deutsche Werft (English: German Shipyard) was a shipbuilding company in Finkenwerder Rüschpark, Hamburg, Germany. It was founded in 1918 by Albert Ballin and with Gutehoffnungshütte (GHH), ''Allgemeine Elektricitäts-Gesellschaft'' (AEG) and ' ...
in
Hamburg
(male), (female) en, Hamburger(s),
Hamburgian(s)
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, utc_offset1_DST = +2
, postal ...
on 17 April 1944. It was one of six XXIIIs that went on operational patrol around the
British Isles
The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, ...
in early 1945. Forty-eight others followed from
Deutsche Werft
Deutsche Werft (English: German Shipyard) was a shipbuilding company in Finkenwerder Rüschpark, Hamburg, Germany. It was founded in 1918 by Albert Ballin and with Gutehoffnungshütte (GHH), ''Allgemeine Elektricitäts-Gesellschaft'' (AEG) and ' ...
and fourteen from
Germaniawerft of
Kiel
Kiel () is the capital and most populous city in the northern Germany, German state of Schleswig-Holstein, with a population of 246,243 (2021).
Kiel lies approximately north of Hamburg. Due to its geographic location in the southeast of the J ...
. was the last one launched, on 1 March 1945.
Service history
None of the six operational Type XXIIIs - , , , , and - were sunk by the Allies' ships but they sank four ships for a total of .
The first war patrol of a Type XXIII began late in the war when sailed from Kiel on 18 January 1945. Although she was to survive the war, she sank no enemy vessels. The first Type XXIII to achieve combat success was , commanded by ''
Oberleutnant zur See
''Oberleutnant zur See'' (''OLt zS'' or ''OLZS'' in the German Navy, ''Oblt.z.S.'' in the '' Kriegsmarine'') is traditionally the highest rank of Lieutenant in the German Navy. It is grouped as OF-1 in NATO.
The rank was introduced in the Imp ...
'' Fridtjof Heckel. Sailing from a Norwegian base on 6 February 1945, she encountered a convoy off
Berwick,
Northumberland
Northumberland () is a county in Northern England, one of two counties in England which border with Scotland. Notable landmarks in the county include Alnwick Castle, Bamburgh Castle, Hadrian's Wall and Hexham Abbey.
It is bordered by land on ...
, and sank the
coaster
Coaster (stylized as COASTER) is a commuter rail service in the central and northern coastal regions of San Diego County, California, United States operated by the North County Transit District (NCTD). The commuter rail line features eight s ...
''Egholm'' on 25 February. , operating from the same base, sank the coaster ''Gasray'' on 5 April 1945 off
St Abbs Head. , under the command of ''
Kapitänleutnant
''Kapitänleutnant'', short: KptLt/in lists: KL, ( en, captain lieutenant) is an officer grade of the captains' military hierarchy group () of the German Bundeswehr. The rank is rated OF-2 in NATO, and equivalent to Hauptmann in the Heer and ...
'' Emil Klusmeier, later sank the last Allied ships lost in the European war on 7 May 1945, when he torpedoed and sank the freighters ''
Sneland I'' and off the
Isle of May
The Isle of May is located in the north of the outer Firth of Forth, approximately off the coast of mainland Scotland. It is about long and wide. The island is owned and managed by NatureScot as a national nature reserve. There are now no ...
inside the
Firth of Forth
The Firth of Forth () is the estuary, or firth, of several Scottish rivers including the River Forth. It meets the North Sea with Fife on the north coast and Lothian on the south.
Name
''Firth'' is a cognate of ''fjord'', a Norse word meani ...
.
The ''Sneland I'' and the ''Avondale Park'' were sunk around 23:03, less than an hour before the official German surrender, and the ''Avondale Park'' was the last merchant ship to be sunk by a U-boat. At the time it was felt that Kapitänleutnant Klusmeier, who was on his first patrol, had deliberately ignored Dönitz's ceasefire order; however, Klusmeier claimed that he had never received the order.
Losses
Seven Type XXIIIs were lost to various causes.
* was sunk by a
naval mine
A naval mine is a self-contained explosive device placed in water to damage or destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, any ...
on 26 July 1944.
* was lost in a training accident on 10 October 1944.
* was sunk by British
Beaufighter
The Bristol Type 156 Beaufighter (often called the Beau) is a British multi-role aircraft developed during the Second World War by the Bristol Aeroplane Company. It was originally conceived as a heavy fighter variant of the Bristol Beaufort ...
aircraft which killed 12 crewmen and sank the boat east-northeast of
Fredericia
Fredericia () is a town located in Fredericia Municipality in the southeastern part of the Jutland peninsula in Denmark. The city is part of the Triangle Region, which includes the neighbouring cities of Kolding and Vejle. It was founded in 16 ...
in Denmark on 4 May 1945, before she ever went on combat patrol.
* was
mined and sunk on 26 December 1944.
* was accidentally rammed and sunk by on 18 February 1945.
* was sunk by Allied aircraft on 2 May 1945.
* was accidentally rammed and sunk by an unidentified U-boat on 5 May 1945.
In early May 1945, 31 XXIIIs were scuttled by their crews. 20 surrendered to the Allies and were sunk in
Operation Deadlight
Operation Deadlight was the code name for the Royal Navy operation of November 1945 – February 1946 to scuttle German U-boats surrendered to the Allies after the defeat of Germany near the end of World War II.
Operation
Of the 156 U-boats ...
. Only 3 – (later British submarine ''N35''), (later British submarine ''N31'', then Soviet submarine ''M-51''), and (later Norwegian submarine ''Knerter'') – survived the war.
Postwar
One Type XXIII was allocated to the Soviet Union under the terms of the
Potsdam Agreement
The Potsdam Agreement (german: Potsdamer Abkommen) was the agreement between three of the Allies of World War II: the United Kingdom, the United States, and the Soviet Union on 1 August 1945. A product of the Potsdam Conference, it concerned th ...
, and a second unit was reportedly salvaged in 1948.
[
In 1956, the ]Bundesmarine
The German Navy (, ) is the navy of Germany and part of the unified ''Bundeswehr'' (Federal Defense), the German Armed Forces. The German Navy was originally known as the ''Bundesmarine'' (Federal Navy) from 1956 to 1995, when ''Deutsche Mari ...
raised two Type XXIII boats, '' U-2365'' (scuttled in the Kattegat
The Kattegat (; sv, Kattegatt ) is a sea area bounded by the Jutlandic peninsula in the west, the Danish Straits islands of Denmark and the Baltic Sea to the south and the provinces of Bohuslän, Västergötland, Halland and Skåne in Sweden ...
in 1945) and '' U-2367'' (which sank near following a collision with another U-boat), and recommissioned them as '' U-Hai'' (Shark) and ''U-Hecht'' (Pike), with pennant numbers S 170 and S 171 respectively. ''U-Hai'' sank in a gale off the Dogger Bank
Dogger Bank (Dutch: ''Doggersbank'', German: ''Doggerbank'', Danish: ''Doggerbanke'') is a large sandbank in a shallow area of the North Sea about off the east coast of England.
During the last ice age the bank was part of a large landmass ...
in September 1966, taking 19 of her 20 crewmen with her. Her loss is the greatest maritime post-war disaster that the German Navy
The German Navy (, ) is the navy of Germany and part of the unified ''Bundeswehr'' (Federal Defense), the German Armed Forces. The German Navy was originally known as the ''Bundesmarine'' (Federal Navy) from 1956 to 1995, when ''Deutsche Mari ...
has suffered. The experience gained from the two recommissioned submarines led to the construction of the Type 206 submarine
The Type 206 is a class of diesel-electric submarines (U-boats) developed by Howaldtswerke-Deutsche Werft (HDW). Its design is based on the preceding Type 205 submarine class. These small and agile submarines were built during the Cold War to op ...
, which was in use until 2011.
Boats in class
Although a total of 980 Type XXIII submarines were planned, many were scrapped incomplete (or indeed never ordered in many cases), only the following 61 vessels were built:
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See also
*British R-class submarine
The R-class submarines were a class of 12 small British diesel-electric submarines built for the Royal Navy during World War I, and were forerunners of the modern attack submarine, in that they were designed specifically to attack and sink enemy ...
References
Bibliography
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External links
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{{DEFAULTSORT:Type 023 Submarine
Submarine classes
World War II submarines of Germany