German submarine ''U-1224'' was a Type IXC/40

U-boat U-boats were naval submarines operated by Germany, particularly in the First and Second World Wars. Although at times they were efficient fleet weapons against enemy naval warships, they were most effectively used in an economic warfare role ...

Nazi Germany Nazi Germany (lit. "National Socialist State"), ' (lit. "Nazi State") for short; also ' (lit. "National Socialist Germany") (officially known as the German Reich from 1933 until 1943, and the Greater German Reich from 1943 to 1945) was ...

's ''

Kriegsmarine The (, ) was the navy of Germany from 1935 to 1945. It superseded the Imperial German Navy of the German Empire (1871–1918) and the inter-war (1919–1935) of the Weimar Republic. The was one of three official branches, along with the a ...

'' built for service during

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 ...

. She was constructed by

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 ' ...

Hamburg (male), (female) en, Hamburger(s), Hamburgian(s) , timezone1 = Central (CET) , utc_offset1 = +1 , timezone1_DST = Central (CEST) , utc_offset1_DST = +2 , postal ...

, used as a training ship for Japanese sailors, and transferred into Japanese service on 15 February 1944. In the

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, when it was dissolved following Japan's surrender ...

, she served as ''Ro-501'' until sunk on 13 May 1944.

Design

German Type IXC/40 submarines were slightly larger than the original Type IXCs. ''U-1224'' had a displacement of when at the surface and while submerged. The U-boat had a total length of , a

pressure hull A submarine hull has two major components, the ''light hull'' and the ''pressure hull''. The light hull (''casing'' in British usage) of a submarine is the outer non-watertight hull which provides a hydrodynamically efficient shape. The pressure ...

length of , a

beam Beam may refer to: Streams of particles or energy *Light beam, or beam of light, a directional projection of light energy **Laser beam *Particle beam, a stream of charged or neutral particles **Charged particle beam, a spatially localized grou ...

of , a height of , and a draught of . The submarine was powered by two

MAN A man is an adult male human. Prior to adulthood, a male human is referred to as a boy (a male child or adolescent). Like most other male mammals, a man's genome usually inherits an X chromosome from the mother and a Y chromos ...

M 9 V 40/46

supercharged In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorisation is that a supercharger is a form of forced induct ...

four-stroke, nine-cylinder

diesel engine The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-call ...

s producing a total of for use while surfaced, two

Siemens-Schuckert Siemens-Schuckert (or Siemens-Schuckertwerke) was a German electrical engineering company headquartered in Berlin, Erlangen and Nuremberg that was incorporated into the Siemens AG in 1966. Siemens Schuckert was founded in 1903 when Siemens & Ha ...

2 GU 345/34 double-acting electric motors producing a total of for use while submerged. She had two shafts and two

propeller A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...

s. The boat was capable of operating at depths of up to . The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at . ''U-1224'' was fitted with six

torpedo tube A torpedo tube is a cylindrical device for launching torpedoes. There are two main types of torpedo tube: underwater tubes fitted to submarines and some surface ships, and deck-mounted units (also referred to as torpedo launchers) installed aboa ...

s (four fitted at the bow and two at the stern), 22

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, one SK C/32 naval gun, 180 rounds, and a Flak M42 as well as two twin C/30 anti-aircraft guns. The boat had a

complement A complement is something that completes something else. Complement may refer specifically to: The arts * Complement (music), an interval that, when added to another, spans an octave ** Aggregate complementation, the separation of pitch-class ...

of forty-eight.

FLAK weaponry

''U-1224''/''Ro-501'' was mounted with a single 3.7 cm Flakzwilling M43U gun on the LM 42U mount. The LM 42U mount was the most common mount used with the 3.7 cm Flak M42U. The 3.7 cm Flak M42U was the marine version of the 3.7 cm Flak used by the

Type VII Type VII U-boats were the most common type of German World War II U-boat. 703 boats were built by the end of the war. The lone surviving example, , is on display at the Laboe Naval Memorial located in Laboe, Schleswig-Holstein, Germany. Conc ...

and

Type IX The Type IX U-boat was designed by Nazi Germany's '' Kriegsmarine'' in 1935 and 1936 as a large ocean-going submarine for sustained operations far from the home support facilities. Type IX boats were briefly used for patrols off the eastern Un ...

U-boats. File:3.7cm Flak M42 LM42U.png, A single 3.7 cm Flak M42U gun on the LM 42U mount.

Service history

''Kriegsmarine''

The submarine's keel was

laid down Laying the keel or laying down is the formal recognition of the start of a ship's construction. It is often marked with a ceremony attended by dignitaries from the shipbuilding company and the ultimate owners of the ship. Keel laying is one o ...

on 30 November 1942 by

Blohm & Voss Blohm+Voss (B+V), also written historically as Blohm & Voss, Blohm und Voß etc., is a German shipbuilding and engineering company. Founded in Hamburg in 1877 to specialise in steel-hulled ships, its most famous product was the World War II battle ...

of Hamburg. It was commissioned on 20 October 1943. ''U-1224'' was used as a training ship for Japanese sailors, and engaged in technology transfer activities. It began its career doing training for Japanese sailors who had arrived as part of the

Yanagi missions The , or more formally the , were a series of submarine voyages undertaken by the Imperial Japanese Navy (IJN) during the Second World War, to exchange technology, skills and materials with Japan's Axis partners, principally Nazi Germany. These v ...

. A small crew of ''Kriegsmarine'' sailors trained 48 Japanese sailors at sea in the Baltic from October 1943 until February 1944.

Imperial Japanese Navy

After the crew underwent three months of training, ''U-1224'' was recommissioned into the

as ''Ro-501''. Captain Narita was put in charge of the crew, and ''Ro-501'' was then tasked to carry a load of war materials, blueprints, and other secret cargo from Kiel, Germany to

Penang Penang ( ms, Pulau Pinang, is a Malaysian state located on the northwest coast of Peninsular Malaysia, by the Malacca Strait. It has two parts: Penang Island, where the capital city, George Town, is located, and Seberang Perai on the Malay ...

, Malaysia. The mission was never completed.

Technology Transfer

Germany and Japan were separated by great distance, and by 1944 they were increasingly cut off from each other. While neither power was able to send meaningful reinforcements or armaments through territory controlled by the Allied powers, they were able to use submarines to share some intelligence and weapons blueprints. Submarines offered security and their stealth allowed for a fair chance of success. Between 1942 and 1944, approximately 35 submarines attempted the journey from Europe to the Far East, and at least 11 attempted the journey from the Far East to Europe. On its journey from Germany to Malaysia, ''Ro-501'' carried precious metals, uncut optical glass, models and blueprints necessary to construct a

Type IX U-boat The Type IX U-boat was designed by Nazi Germany's ''Kriegsmarine'' in 1935 and 1936 as a large ocean-going submarine for sustained operations far from the home support facilities. Type IX boats were briefly used for patrols off the eastern Unit ...

in addition to motors and blueprints for the Messerschmitt

Me 163 The Messerschmitt Me 163 Komet is a rocket-powered interceptor aircraft primarily designed and produced by the German aircraft manufacturer Messerschmitt. It is the only operational rocket-powered fighter aircraft in history as well as th ...

"Komet” rocket fighter airplane. It was also hoped that the trained Japanese sailors would pass along their expertise.

Sinking

The intended route to Penang was to take ''Ro-501'' through the middle of the Atlantic Ocean west of the

Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...

and the

Cape Verde , national_anthem = () , official_languages = Portuguese , national_languages = Cape Verdean Creole , capital = Praia , coordinates = , largest_city = capital , demonym ...

islands, then around the

Cape of Good Hope The Cape of Good Hope ( af, Kaap die Goeie Hoop ) ;''Kaap'' in isolation: pt, Cabo da Boa Esperança is a rocky headland on the Atlantic coast of the Cape Peninsula in South Africa. A common misconception is that the Cape of Good Hope is t ...

. She was to rendezvous with ''I-8'' in the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...

to refuel before proceeding to her destination.Hackett and Kingsepp, ''IJN Submarine RO-501 (ex-U-1224): Tabular Record of Movement'' However, at , ''Ro-501'' ran into a

U.S. Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of ...

hunter-killer group comprising

escort carrier The escort carrier or escort aircraft carrier (U.S. hull classification symbol CVE), also called a "jeep carrier" or "baby flattop" in the United States Navy (USN) or "Woolworth Carrier" by the Royal Navy, was a small and slow type of aircraft ...

and five

destroyer escort Destroyer escort (DE) was the United States Navy mid-20th-century classification for a warship designed with the endurance necessary to escort mid-ocean convoys of merchant marine ships. Development of the destroyer escort was promoted by th ...

s, including . The group's presence forced ''Ro-501'' underwater for two days, during which her batteries were depleted and her captain radioed a coded signal that he was being pursued. This transmission was detected by the American ships with their

high-frequency direction finding High-frequency direction finding, usually known by its abbreviation HF/DF or nickname huff-duff, is a type of radio direction finder (RDF) introduced in World War II. High frequency (HF) refers to a radio band that can effectively communicate over ...

("Huff-Duff") equipment, enabling them to pinpoint the submarine's location. The ''Francis M. Robinson'' reported a submerged contact at 19:00 on 13 May 1944. The destroyer escort engaged the contact with a full salvo from its forward-throwing

Hedgehog A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are seventeen species of hedgehog in five genera found throughout parts of Europe, Asia, and Africa, and in New Zealand by introducti ...

mount, followed by five salvos of

magnetic proximity fuze A magnetic proximity fuse was patented by P.J. Eliomarkakis, (United States Patent US2434551 of January 13, 1948) although similar devices had been in service for nearly a decade. It is a type of proximity fuze that initiates a detonator in a pi ...

depth charge A depth charge is an anti-submarine warfare (ASW) weapon. It is intended to destroy a submarine by being dropped into the water nearby and detonating, subjecting the target to a powerful and destructive Shock factor, hydraulic shock. Most depth ...

s. Four underwater explosions were detected. All 56 hands aboard were lost - 52 crew (including a German radar operator and a German pilot) plus four IJN officer passengers. The final resting place of ''U-1224''/''Ro-501'' is west-northwest of the Cape Verde islands at in of water. This is a few miles from where sank .

References

Bibliography

* * *

External links

Wreck information for the RO-501
*

* {{DEFAULTSORT:U1224 German Type IX submarines U-boats commissioned in 1944 World War II submarines of Germany World War II submarines of Japan 1943 ships Ships built in Hamburg U-boats sunk in 1944 U-boats sunk by US warships U-boats sunk by depth charges Foreign submarines of the Imperial Japanese Navy Ships lost with all hands Maritime incidents in May 1944 World War II shipwrecks in the Atlantic Ocean