Porpoise class (1933)

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Porpoise class
Royal Navy
HMS Rorqual in April 1943
General data
Ship type : Submarine
Navy : Royal Navy
Builders :
Units: 6th
Boats of the class
Cachalot , Grampus , Narwhal , Porpoise , Rorqual , Seal
Technical data HMS Grampus
Crew : 59 men
Displacement :
  • over water: 1810  ts
  • under water: 2157 ts
Length : 89.1 m
Width: 7.7 m
Draft : 5.1 m
Drive  :
Speed :
  • surfaced: 15.75 kn (29.2 km / h )
  • submerged: 8.75 kn (16 km / h)
Driving range  :
  • above water at 9.3 Kn:
    • 5880 NM (10890 km)
  • under water at 4 kn:
    • 64 NM (119 km)
Diving depth : maximum 90 m
Armament
Artillery : 1 * 4 ″ (101.6-mm) deck gun
Air defense : 2 * .303 - Lewis MG (7.7mm)
Torpedo tubes : 6 * 21 ″ (533-mm) tubes (12 torpedoes )
Sea mines : 50 mines

The Porpoise-class was a class of submarines used by the British Royal Navy during World War II . In the literature, the underground mine layers are sometimes referred to as the Grampus class .

Building history

In World War I the British arms industry developed the cruiser submarine of the M-Class . The submarine monitors , originally armed with extremely heavy artillery , were used as test vehicles for various operational concepts after the end of the war. I.a. the HMS M3 was converted into a minesheet. The mine-laying system of the test submarine proved its worth, which is why the construction of a large mine-laying submarine was approved in the British budget of 1930.

The prototype HMS Porpoise was launched in 1932 and entered service in 1933. The design was further developed and enlarged. The bow was redesigned and the magazine for the sea mines was extended. By 1939 another five submarines of the class were put into service.

After the outbreak of World War II, three more submarines of the class were ordered in 1940. The building contract was withdrawn in September 1941. The Royal Navy had meanwhile developed new sea ​​mines based on the German and US models , which could be ejected through a standard torpedo tube . As a result of this development, the construction of special sub-minelayers no longer seemed sensible, since any submarine armed with standard torpedo tubes could now lay sea mines.

Constructive features

The submarines had a conventional hybrid drive consisting of two diesel engines for surface travel and two electric motors for diving operations. The drive power was transferred to two propellers .

The overwater range of the submarines was 5880 nautical miles (10890 km). The lead accumulators allowed submerged sailing ranges of up to 64 nautical miles (119 km).

The most important structural feature of the submarines was the mine-laying system. Other mine-laying submarines, such as the French Saphir class or the Polish Wilk class , also built in France , sometimes used more than 16 vertical shafts, each of which housed one or two mines. The British construction already tested on the M3 is more comparable to the throwing system of the Russian submarine Krab from the First World War.

The transport and installation unit was located in a saddle tank above the pressure hull. The mines were stored on rails. When laying, they were pulled with a chain mechanism to a hatch at the rear and ejected there. The construction resembled a conveyor belt . The Porpoise mine system began 19 meters behind the bow of the boat. In the boats of the class built later, the magazine stretched continuously over the entire length, which meant that up to 50 mines could be carried.

Although the concept of a dedicated underground miner seemed out of date, in practice the Porpoise-class carried the brunt of Britain's submarine mining operations during World War II, because the specialized miners were able to transport far more sea mines than any other submarine of their time, and so they could could also lay considerably faster and more efficiently.

In addition to the excellent mine armament, the submarines had a relatively powerful torpedo armament. Six rechargeable 21- inch (533-mm) torpedo tubes were arranged in the bow . A total of twelve torpedoes were carried. A 4-inch L / 40 (102 mm) cannon served as deck gun . The caliber corresponds to that of the 105 mm guns used on the German Type IX boats . The air defense weaponry was equipped with two .303 - (7.7 mm) - Lewis - machine guns very weak.

Differences between Porpoise and Grampus

The following information comes from Robert Hutchinson and in some cases differs considerably from the values ​​given above by Erminio Bagnascos : (see: Literature )

                                                               Porpoise Grampus
Crew: 55 men 59 men
Displacement (above water): 1500 ts 1520 ts
Displacement (submerged): 2053 ts 2117 ts
Length over all: 87.78 m 89.31 m
maximum width: 9.08 m 7.77 m
Maximum speed (over water): 15.5 kn (28.7 km / h) 16.0 kn (29.6 km / h)

Mission history

At the beginning of the Second World War, only the Porpoise was stationed in Great Britain. The Cachalot and the Narwhal were in the Mediterranean. The Rorqual was operating in Chinese waters while Seal and Grampus were sailing to China. After fighting broke out in September 1939, Seal and Narwhal were ordered to the North Sea. Rorqual and Grampus were sent to the Mediterranean. In the months that followed, the submarines laid mine blocks in the North Sea. Shortly before the German invasion of Norway and Denmark on April 9, 1940, operations were concentrated on the Kattegat to block the German approach routes.

The class saw its first combat successes in April. (see fight successes ) In the same month, however, there was also the first own loss. The Seal was badly damaged on April 27, 1940 by the explosion of its own mine and then fell into German hands. The Navy took over the submarine and put it into service as a UB .

After the German invasion of Western Europe on May 13, 1940, the Italian entry into the war on June 10 and the subsequent de facto surrender of France on June 22, the submarines were also actively used in the Bay of Biscay and the Mediterranean Sea , in addition to other operations off Norway .

The Grampus , now stationed in Malta , after she had previously unsuccessfully attacked Italian ships with torpedoes, was on June 16, 1940 105 nautical miles east of the Sicilian city ​​of Syracuse by the three Italian torpedo boats Circe , Clio and Polluce at position 37 ° 5 ′  N , 17 ° 30 '  O sunk.

The next loss followed a month later. The Narwhal was on its way to the Norwegian coast to mine sea ​​areas off Kristiansand . It was sunk on July 23, 125 nautical miles east of Aberdeen at position 56 ° 50 '  N , 1 ° 40'  E by a German Do-17 bomber .

Between April and July 1940, half of the Porpoise class was lost.

The remaining three submarines, Cachalot , Porpoise and Rorqual , operated from besieged Malta for the next three years and took part in the defensive battle of the strategically important Mediterranean island against the initially superior Axis powers . During the war in North Africa, the British underground miners fought against the Axis' supply routes throughout the Mediterranean and achieved various successes against Italian and German units with both sea mines and direct torpedo attacks.

The intensive effort required another loss. On July 30, 1941, the Cachalot attacked the Italian freighter Capo Orso with its deck gun at position 32 ° 49 ′  N , 20 ° 11 ′  E 45 nautical miles north of the Libyan port city of Benghazi . The escorting Italian torpedo boat Generale Achille Papa sank the British attacker by means of a determined ramming attack.

After the last German-Italian units in North Africa had capitulated on May 13, 1943, Allied forces landed in southern Italy on July 10, 1943 as part of Operation Husky , and Italy withdrew from the war in September 1943, the war in the Mediterranean was finally decided and also became a secondary theater of war from a British perspective. The two remaining submarines of the class were withdrawn from the Mediterranean Sea in 1944 for use in the Pacific War against Japan. By the end of the war in September 1945, several Japanese ships were sunk with both sea mines and direct torpedo and artillery attacks.

On January 19, 1945, the Porpoise in Malakka Street was sunk by Japanese aircraft. This was the Royal Navy's 77th and final submarine loss in World War II.

The Rorqual was the only boat in the class to survive the war. It was sold on December 19, 1945 and scrapped in March 1946.

The submarines laid about 2600 sea mines during the war:

  • Rorqual : 1284
  • Porpoise : 465
  • Narwhal : 450
  • Cachalot : 300
  • Grampus : 50
  • Seal : 50

Battle successes (selection)

1940

  • April 14th: The German auxiliary minesweeper M 1101 / Fock and Hubert runs off Skagen on a sea ​​mine laid by Narwhal the day before and is badly damaged. The ship later runs aground and is abandoned.
  • April 23rd: The German auxiliary minesweeper M 1302 / Schwaben runs off Skagen on a sea ​​mine laid by Narwhal on April 13th and sinks.
  • May 1: Narwhal attacks two German troop carriers with torpedoes in the Skagerrak . The Buenos Aires sinks and the Bahia Castillo is badly damaged.
  • May 3: The German auxiliary minesweeper M 1102 / HAW Möller sinks in the Skagerrak after a mine hit. The mine was laid by Narwhal on May 1st.
  • May 6: The German transport ship Vosges sinks in the Kattegat after a mine hit. The sea mines come from the Seal .
  • May 30th: The German outpost boat V 1109 / Antares runs off Molde on a mine laid by Narwhal on May 11th and sinks.
  • June 5: The German minesweeper M 11 and the German freighter Palime run off of Feiestein on sea ​​mines laid by Narwhal two days earlier. The mine sweeper sinks immediately. The merchant ship runs aground and is abandoned.
  • June 18: The German minesweeper M 4 sinks northwest of Kristiansand after a mine hit. The mines were laid by Porpoise four days earlier .
  • June 26th: The Italian merchant ship Loasso runs off Torre Preposti ( Apulia ) on a sea ​​mine laid by Rorqual and sinks.
  • July 6th: The German auxiliary U-Jäger UJ D / Treff VIII sinks off the Norwegian coast after being hit by a mine. The sea mines were laid by Narwhal on July 4th .
  • July 24th: The Italian transporter Celio runs off the Libyan coast on a sea ​​mine laid by Rorqual on July 21st and sinks.
  • August 14: Rorqual lays sea mines off the Libyan coast. On the same day, the Italian freighter Leopardi sinks through one of these mines.
  • August 20: Cachalot sinks the German submarine U 51 with torpedoes in the Bay of Biscay .
  • September 23: The German auxiliary minesweeper M 1604 / Austria runs into a sea ​​mine laid by Cachalot in the Biscaya and sinks.
  • September 25: The Italian pilot boat F 34 / Rina Croce sinks through a sea mine off Brindisi . The minefield was laid by Rorqual on June 14th .
  • October 13th: The three German minesweepers Gnom , Kobold 1 and Kobold 3 sink off the Osterfjord after being hit by mines. The mines were laid by Narwhal on June 12th .
  • December 5: The Italian torpedo boat Calipso runs off Misratah on a sea ​​mine laid by Rorqual and sinks.
  • December 23: The Italian torpedo boat Fratelli Cairoli runs off Misratah on a sea ​​mine laid by Rorqual and sinks.

1941

  • January 31: The Rorqual sinks the armed Italian tug Ursus off Dubrovnik during an artillery duel and damages an artillery platform.
  • March 25th: An Italian convoy gets into a minefield laid by Rorqual the day before in Capo Gallo (Sicily) . The freighters Verde and Ticino are sinking.
  • March 28th: ​​The Italian torpedo boat Generale Antonio Chinotto sinks in the same minefield off Capo Gallo.
  • March 30th: Rorqual torpedoed and sank the Italian tanker Laura Corrado off Capo Gallo .
  • March 31: Rorqual torpedoed and sank the Italian submarine Pier Capponi south of Stromboli off Capo Gallo .
  • August 28: The Rorqual torpedoed and sank the Italian transporter Cilicia southwest of the Ionian island of Schiza .
  • October 20: The Italian torpedo boats Altair and Aldebaran sink in the Saronic Gulf after being hit by mines. The minefield was laid by Rorqual on October 8th .
  • December 9: South of Pylos, Porpoise torpedoed the Italian transporter Sebastiano Venier , which subsequently ran aground. There are 1,800 Allied prisoners of war on board. Despite bad weather conditions, over 1700 men can be saved.

1942

  • January 18: Porpoise sinks the Italian merchant ship Citta di Livorno northeast of Cape Maleka ( Crete ) with torpedoes.
  • February 9: The Italian transport ship Salpi sinks off Capo Ferrato ( Sardinia ) due to a mine hit. The mines were laid by Rorqual on October 22, 1941 .
  • August 12: Porpoise torpedoed and sank the Italian transporter Ogaden off Ras El Tin (Libya) .
  • August 15: Porpoise torpedoed and sank the Italian freighter Lerici off Ras Amir (Libya) .
  • August 22nd: The Italian torpedo boat Generale Antonio Cantore sinks west of Tobruk (Libya) as a result of a mine hit. The minefield was laid by Porpoise ten days earlier .
  • August 30: Rorqual torpedoed and sank the Italian transport ship Monstella in the Ionian Sea .
  • November 18: Porpoise torpedoes and sinks the Italian tanker Giulio Giordani northeast of Misurata (Libya).
  • November 23: Porpoise sinks the Italian outpost boat F 39 / Fertilla with the deck gun off Sfax (Tunisia) .

1943

  • January 18: The German troop transport Ankara runs north-east of Tenedos on a sea ​​mine laid by Rorqual on the same day and sinks.
  • July 7th: Rorqual torpedoed and sank the German tanker Wilhelmsburg west of Tenedo .
  • August 7th: Rorqual torpedoed and sunk the French transporter Nantaise in the Aegean Sea .
  • September 7th: The French transport ship PLM 24 runs north of Skiathos on a sea ​​mine laid by Rorqual .

1944

  • July 6th: Porpoise sinks a small Japanese sailing ship with the deck gun in Malakka Street.
  • September 9th: The two Japanese auxiliary submarines Cha 8 and Cha 9 run north of Medan ( Sumatra ) on sea mines and sink. The minefield was laid by Porpoise between July 6th and 8th.
  • September 10: The Japanese tanker Takekum Maru sinks off Medan as a result of a mine hit. The minefield was laid by Porpoise between July 6th and 8th.

1945

  • January 15: The Japanese auxiliary minesweeper Kyo Maru 1 runs off Penang (Malaysia) on a mine laid by Porpoise on January 9 and sinks.
  • March 25: Rorqual sinks a small Japanese sailing ship with the deck gun west of Sumatra.
  • March 27th: The Japanese auxiliary minesweeper Ma 1 sinks off Medan (Sumatra) after being hit by a mine . The minefield was laid by Porpoise between July 6th and 8th, 1944 . On the same day, Rorqual sank two small Japanese coasters with the deck gun west of Sumatra and damaged another one.
  • April 2: Rorqual sinks two Japanese sailing ships with the deck gun west of Sumatra.
  • May 11th: Rorqual sinks a Japanese coaster with the deck gun in the western Java Sea .

Boats of the class

Five boats were lost in the war. One survived the war. Three units were only planned, but never built.

          boat                  Shipyard              Keel laying              Launch         Commissioning  Whereabouts
HMS Porpoise
(N 14) 		Vickers-Armstrong September 22, 1931 August 30, 1932 March 11, 1933 Sunk by Japanese aircraft on January 16, 1945 in the Strait of Malacca.
HMS Grampus
(N 56) 		Chatham Dockyard August 20, 1934 February 25, 1936 March 10, 1937 Sunk by Italian torpedo boats off Syracuse on June 16, 1940.
HMS Narwhal
(N 45) 		Vickers-Armstrong May 29, 1934 August 29, 1935 February 28, 1936 Sunk by German aircraft on July 30, 1940 off Aberdeen.
HMS Rorqual
(N 74) 		Vickers-Armstrong May 1, 1935 July 21, 1936 February 10, 1937 Sold for scrapping on March 17, 1946.
HMS Cachalot
(N 83) 		Scott's May 12, 1936 December 2, 1937 August 15, 1938 On July 30, 1941, an Italian torpedo boat rammed and sunk off Benghazi.
HMS Seal
(37 M) 		Chatham Dockyard December 9, 1936 September 27, 1938 May 24, 1939 Attacked by German units in the Kattegat on May 4, 1940. Commissioned as UB on November 30, 1940 . Decommissioned July 31, 1941 and self-sunk on May 3, 1945.
(P 411) Scott's Order canceled in January 1941
(P 412) Scott's Order canceled in January 1941
(P 413) Scott's Order canceled in January 1941

See also

literature

  • Erminio Bagnasco: Submarines in World War II. 5th edition. Motorbuchverlag, Stuttgart 1996, ISBN 3-613-01252-9 .
  • Robert Hutchinson: Fight Under Water - Submarines from 1776 to the Present. 1st edition. Motorbuchverlag, Stuttgart 2006, ISBN 3-613-02585-X .
  • Anthony Preston: The History of the Submarines. Karl Müller Verlag, Erlangen 1998, ISBN 3-86070-697-7 .
  • Chris Chant: Modern Submarines Engineering Tactics Armament. 1st edition. Motorbuchverlag, Stuttgart 2005, ISBN 3-7276-7150-5 .

Web links

Commons : Porpoise class  - collection of images, videos, and audio files

Footnotes

  1. ↑ a b Erminio Bagnasco gives a crew of 59 men for all boats. The uboat.net gives 59 men (6 officers and 53 men) for all boats. Robert Hutchinson gives 55 men for HMS Porpoise and 59 for HMS Grampus .
  2. ↑ a b Bagnasco gives the HMS Grampus 1810 ts as the overwater displacement . The HMS Porpoise displaced over water to Bagnasco in 1782 ts. The uboat.net gives 1768 ts for all boats. Hutchinson gives 1500 ts for the HMS Porpoise and 1520 ts for the HMS Grampus .
  3. ↑ a b Bagnasco gives 2157 ts for the underwater displacement of the HMS Grampus . Hutchinson specifies ts for the HMS Grampus 2117. The HMS Porpoise displaced, according to Bagnasco and Hutchinson 2053 dipped ts. Uboat.net gives 2035 ts for all boats. Possibly a typo ?
  4. ↑ a b Bagnasco gives the length of all boats as 89.1 m. Hutchinson gives 87.78 m for the HMS Porpoise and 89.31 m for the HMS Grampus . The uboat.net gives 88 m (289 ft ) for all boats .
  5. ↑ a b Bagnasco gives a maximum width of 7.7 m for all boats. Hutchinson gives 9.08 m for the HMS Porpoise and 7.77 m for the HMS Grampus . The uboat.net gives 9.09 m (29 ft 10 ″ ) for all boats .
  6. ↑ Bagnasco gives a draft of 5.1 m for all boats. The uboat.net gives 4.84 m (15 ft 10 ″) for all boats. Hutchinson makes no statement.
  7. ↑ a b According to Bagnasco, HMS Grampus reached a speed of 15.75 kn (29.2 km / h) and HMS Porpoise only 15 kn (27.8 km / h) over water . Hutchinson specifies 16 kn (29.6 km / h) for HMS Porpoise and 15.5 kn (28.7 km / h) for HMS Grampus . The uboat.net gives 15.75 kn for all submarines. The different information is certainly due to rounding errors.
  8. ↑ a b Bagnasco states 6300 NM (11670 km) for the HMS Porpoise and 5880 NM (10890 km) for the HMS Grampus . Hutchinson gives twice the value for all boats with 11500 NM (21300 km). Compared to the similar M-Class , Bagnasco's statement seems to be more realistic. The uboat.net gives no value.
  9. ↑ Hutchinson specifies a maximum diving depth of 90 meters for both Porpoise and Grampus . All other sources mentioned make no statement.
  10. ↑ HMS is the abbreviation for His / Her Majesty's Ship and the name prefix of British ships. HMS means His / Her Majesty's Ship .
  11. ↑ In the English language Porpoise means bottlenose dolphin or harbor porpoise .
  12. ↑ In the English language, Grampus means round head dolphin .
  13. ↑ In the English language means Narwhal Narwal .
  14. ↑ In the English language Rorqual means furrow whale .
  15. ↑ In the English language means Cachalot mutatis mutandis sperm whale .
  16. ↑ In the English language seal means harbor seal or eared seal .