BETASOM

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BETASOM
Bordeaux Sommergibili
Bordeaux, France
Basesousmarine.JPG
France location map-Regions and departements-2016.svg
Red pog.svg
BETASOM
Coordinates 44°52′03″N0°33′34″W / 44.867534°N 0.559341°W / 44.867534; -0.559341
TypeSubmarine base
Site information
Controlled byFlag of Italy (1861-1946) crowned.svg  Kingdom of Italy
Site history
In useAugust 1940 – September 1943
Battles/wars Battle of the Atlantic
Garrison information
Past
commanders
Angelo Parona (August 1940 – September 1941)
Romolo Polacchini (September 1941 – December 1942)
Enzo Grossi (December 1942 – September 1943)
Garrison1,600
OccupantsFlag of Italy (1861-1946) crowned.svg  Regia Marina

BETASOM (an Italian language acronym of Bordeaux Sommergibile or Sommergibili) [lower-alpha 1] was a submarine base established at Bordeaux, France by the Regia Marina Italiana during World War II. From this base, Italian submarines participated in the Battle of the Atlantic from 1940 to 1943 as part of the Axis anti-shipping campaign against the Allies.

Contents

Establishment

Axis naval co-operation started after the signing of the Pact of Steel in June 1939 with meetings in Friedrichshafen, Germany, and an agreement to exchange technical information. After the Italian entry into the war and the Fall of France, the Italian Royal Navy established a submarine base at Bordeaux, which was within the German occupation zone. The Italians were allocated a sector of the Atlantic south of Lisbon to patrol. The base was opened in August 1940, and in 1941 the captured French passenger ship De Grasse was used as a depot ship before being returned to the Vichy French Government in June 1942.

Admiral Angelo Parona commanded the submarines at BETASOM under the operational control of Konteradmiral (Rear Admiral) Karl Dönitz. Dönitz was the "Commander of the Submarines" ( Befehlshaber der U-Boote ) for the German Kriegsmarine . About 1,600 men were based at BETASOM. [1] A postal system was operated, using a distinctive stamp cancellation and overprinted Italian stamps. These are generally rare and have been counterfeited. [2]

The base could house up to thirty submarines, and it had dry docks and two basins connected by locks. Shore barracks accommodated a security guard of 250 men of the San Marco Regiment. A second base was established at La Pallice in La Rochelle, France. This second base allowed submerged training which was not possible at Bordeaux.

Operational detail

From June 1940, three Italian submarines patrolled off the Canary Islands and Madeira, followed by three more off the Azores. When these patrols were completed, the six boats returned to their new base at Bordeaux. Their initial patrol area was the Northwestern Approaches. Dönitz was pragmatic about the Italians, seeing them as inexperienced, but useful for reconnaissance and likely to gain expertise. [3] [4]

In November 1940 there were 26 Italian boats at Bordeaux. [5] Initially, their activity did not meet much success; unacquainted with Atlantic weather conditions, Italian submarines sighted convoys but lost contact and failed to make effective reports. As co-operation between the two navies was not working well, Dönitz decided to reassign the Italian boats to the southern area where they could act independently. [4] In this way, about thirty Italian boats achieved more success, though without much impact on the most critical areas of the campaign. [3] [6]

Italian submarine Barbarigo Barbarigo 1.jpg
Italian submarine Barbarigo

Dönitz considered the Italians as displaying "great dash and daring in battle, often exceeding that of Germans", but less toughness, endurance and tenacity. [7] By 30 November 1940, Italian submarines in the Atlantic each sank an average of 200 gross tons per day, while German U-boats each averaged 1,115 gross tons per day during the same period. Italian submarines, however, had only been in the Atlantic for a few months at this time, and had not had yet the time to adapt to the new operational conditions, whereas the U-boats had already been operating there for more than a year. [4]

In an attempt to improve the performance of the Italian submarines, several measures were taken: taking cue from the Kriegsmarine, older Italian submarine commanders (some were 40 years old) were replaced with younger officers, who possessed more aggressiveness and stamina; a "submarine school" was created in Gotenhafen, where commanders, officers and bridge crews of the BETASOM submarines were trained according to the German model (the submarine Reginaldo Giuliani was assigned to this task, in cooperation with German naval units). [8] :471–481 Italian submarines also underwent improvement work, such as the reshaping of their excessively large conning towers.

These measures significantly improved the performance of the remaining Italian submarines (in 1941, about half were recalled to the Mediterranean following heavy submarine losses in that theatre [4] [5] ); the average tonnage sunk by BETASOM submarines rose from 3,844 Gross Register Tons (GRT) in 1940 to 27,335 GRT in 1942 (and, respectively, from 7,779 GRT to 68,337 GRT per actually operating submarine). [8] :692 The tonnage sunk for every lost submarine was 32,672 GRT in 1940 (opposed to 188,423 GRT for German submarines), 20,432 GRT in 1941 (70,871 GRT for Germans submarines), 136,674 GRT in 1942 (68,801 GRT for German submarines) and 13,498 GRT in 1943 (11,391 GRT for German submarines). [8] :692

Between February and March 1942, five BETASOM submarines (along with six German U-boats) took part in Operation Neuland, sinking 15 of the 45 Allied merchant ships destroyed during this operation. The top scoring BETASOM aces, Gianfranco Gazzana-Priaroggia (90,601 GRT sunk) and Carlo Fecia di Cossato (96,553 GRT sunk), were among the few Italian recipients of the Knight's Cross of the Iron Cross. Gazzana-Priaroggia's boat, Leonardo da Vinci, was the top-scoring non-German submarine of World War II, with 17 ships sunk totalling 120,243 GRT. [9] [10] Another notable Betasom commander was Salvatore Todaro, known for his habit of towing to safety the lifeboats containing the survivors of ships he had sunk.

Italian naval historian Giorgio Giorgerini writes that Italian submarines did not perform as well as the U-boats, but achieved good results considering the deficiencies of their boats (among which were the lack of modern torpedo fire-control systems, and their slower speed both surfaced and submerged). Comparing the respective tonnages sunk by U-boats compared to the Italian submarines and their respective losses (16 Italian submarines lost against 247 U-boats), the respective "exchange rates" (gross tonnage sunk divided by the number of submarines lost) were respectively 40.591 t for the German units and 34.512 t for the Italian ones. [8] :423–425 The strategic significance of Italy's participation in the Battle of the Atlantic was however small, as the number of Italian submarines that operated in the Atlantic was 30 at its peak, whereas the Kriegsmarine committed over 1,000 submarines to the battle of the Atlantic between 1939 and 1945. [8] :424

Overall, Italian submarines operating in the Atlantic sank 109 allied merchant ships totalling 601,425 tons, and lost 16 boats. [11]

German U-boat activities

Remains of U-boat pens in Bordeaux (2009) U-boat pens, Bordeaux, France-1Aug2009.jpg
Remains of U-boat pens in Bordeaux (2009)

Admiral Dönitz decided in mid-1941 to build protective U-boat pens in Bordeaux. Construction began in September 1941. Constructed of reinforced concrete, 245 m (804 ft) wide, 162 m (531 ft) deep, and 19 m (62 ft) high, with a roof above the pens 5.6 m (18 ft 4 in) thick, and 3.6 m (11 ft 10 in) thick above the rear servicing area.

On 15 October 1942, the 12th U-boat Flotilla was formed at Bordeaux by the Kriegsmarine under the command of Korvettenkapitän Klaus Scholtz. The first U-boat to use the bunker was U-178 on 17 January 1943.

End of operations

The base was bombed by the British on several occasions, especially in 1940 and 1941, but no significant damage was suffered, except for the sinking of the barracks ship Usaramo. [12] The base was indirectly attacked by Operation Josephine B in June 1941, a sabotage raid that destroyed the electricity substation that served the base. [13]

The remaining BETASOM boats ended their last offensive patrol in 1943, after which seven BETASOM submarines were adapted to carry critical matériel from the Far East (Bagnolini, Barbarigo, Comandante Cappellini, Finzi, Giuliani, Tazzoli, and Torelli) as part of an agreement between Italy and Germany; Italy had agreed to convert the surviving Betasom submarines, larger than German U-Boats and thus more suited for transport missions, in exchange for the transfer from the Kriegsmarine to the Regia Marina of an equal number of Type VIIC U-Boats, which would be manned by Italian crews and thus continue the Italian participation in offensive submarine operations in the Atlantic. Of the transport submarines, two were sunk by the Allies, three were captured in the Far East by the Japanese after the Italian surrender in the Armistice of Cassibile of September 1943, and ceded to the Germans, and two were captured in Bordeaux by the Germans. The U-Boats ceded to Italy were still training in Danzig with their new Italian crews when the armistice was announced, and were immediately retaken by the Kriegsmarine. Ammiraglio Cagni, the newest Betasom submarine and the only one still on patrol at the time of the armistice, broke off her patrol and reached Durban in South Africa in compliance with the armistice orders. [14]

After the Armistice of Cassibile the base was seized by the Germans. Some of the Italian personnel joined the Germans independently of the Italian Social Republic. During this period the Italian postage stamps on hand were overprinted to show loyalty to Mussolini's rump state. [15]

The last two remaining U-boats left Bordeaux in August 1944, three days before the Allies occupied the base on 25 August. The last remaining German naval personnel attempted to march back to Germany but were captured by US forces on 11 September 1944.

List of submarines operating from BETASOM

In 1940, all twenty-eight Italian submarines which were to be based at BETASOM initially had to sail from bases on the Mediterranean Sea and transit the Straits of Gibraltar to reach the Atlantic Ocean. All twenty-eight did this successfully without incident. [16] [8] :439–470,690–691

Italian submarines at BETASOM [17]
NameArrival dateSuccessesFate/Notes
Alessandro Malaspina 4 Sept 19406 patrols,
3 ships sunk totalling 16,384 GRT
lost with all hands in September 1941
Barbarigo 8 Sept 194011 patrols,
7 ships sunk totalling 39,300 GRT
sunk with all hands by aircraft in June 1943 after conversion into transport submarine
Dandolo 10 Sept 19406 patrols,
2 ships sunk totalling 6554 GRT
returned to the Mediterranean in June–July 1941
Guglielmo Marconi 29 Sept 19406 patrols,
7 ships sunk totalling 19,887 GRT
lost with all hands in September 1941
Giuseppe Finzi 29 Sept 194010 patrols,
5 ships sunk totalling 30,760 GRT
converted into transport submarine and seized after the Italian armistice
Alpino Bagnolini 30 Sept 194011 patrols,
2 ships sunk totalling 6926 GRT
converted into transport submarine and seized after the armistice
Emo 3 Oct 19406 patrols,
2 ships sunk totalling 10,958 GRT
returned to the Mediterranean in August 1941
Capitano Tarantini 5 Oct 19402 patrols,
no ships sunk
sunk by HMS Thunderbolt on 15 December 1940
Luigi Torelli 5 Oct 194012 patrols,
7 ships sunk totalling 42,871 GRT
converted into transport submarine and seized after the armistice
Comandante Faà di Bruno 5 Oct 19402 patrols,
no ships sunk
lost with all hands in October 1940
Otaria 6 Oct 19408 patrols,
1 ship sunk of 4662 GRT
returned to the Mediterranean in September 1941
Maggiore Baracca 6 Oct 19406 patrols,
3 ships sunk totalling 8989 GRT
sunk by HMS Croome on 8 September 1941
Reginaldo Giuliani 6 Oct 19403 patrols,
3 ships sunk totalling 13,603 GRT
transferred for a time to Gdynia to train Italian submariners in U-boat tactics; converted into transport submarine and seized at the armistice
Glauco 22 Oct 19405 patrols,
no ships sunk
sunk by HMS Wishart on 27 June 1941
Pietro Calvi 23 Oct 19408 patrols,
6 ships sunk totalling 34,193 GRT
sunk by HMS Lulworth on 15 July 1942
Enrico Tazzoli 24 Oct 19409 patrols,
18 ships sunk totalling 96,650 GRT
converted into transport submarine and lost with all hands in May 1943
Argo 24 Oct 19406 patrols,
1 ship sunk of 5066 GRT
returned to the Mediterranean in October 1941
Leonardo da Vinci 31 Oct 194011 patrols,
17 ships sunk totalling 120,243 GRT [18]
lost with all hands in May 1943; the best performing non-German submarine in World War II
Veniero 2 Nov 19406 patrols,
2 ships sunk for 4987 GRT
returned to the Mediterranean in August 1941
Nani 4 Nov 19403 patrols,
2 ships sunk totalling 1,939 GRT
lost with all hands in January 1941
Comandante Cappellini 5 Nov 194012 patrols,
5 ships sunk totalling 31,648 GRT
converted into transport submarine and seized after the armistice
Morosini 28 Nov 19409 patrols,
6 ships sunk totalling 40,933 GRT
lost with all hands in August 1942
Marcello 2 Dec 19403 patrols,
1 ship sunk of 1550 GRT
lost with all hands in February 1941
Michele Bianchi 18 Dec 19404 patrols,
3 ships sunk totalling 22,266 GRT
sunk with all hands by HMS Tigris on 4 July 1941
Brin 18 Dec 1940(5 patrols,
2 ships sunk totalling 7241 GRT
returned to the Mediterranean in August–September 1941
Velella 25 Dec 19404 patrols,
no ships sunk
returned to the Mediterranean in August 1941
Mocenigo 26 Dec 19404 patrols,
1 ship sunk of 1253 GRT
returned to the Mediterranean in August 1941

In 1941, another four Italian submarines based in Italian East Africa (Africa Orientale Italiana, or AOI) reached the base after the fall of that colony during the East African Campaign. All four had to travel around the Cape of Good Hope to get to BETASOM.

Transferred from the Red Sea Flotilla during the summer of 1941: [8] :439–470,690–691

Red Sea submarines, transferred to BETASOM [17]
NameArrival dateSuccessesFate/Notes
Archimede 7 May 19413 patrols, 2 ships sunk totalling 25,629 GRTsunk by planes on 15 April 1943
Guglielmotti 7 May 1941no patrols under Betasomreturned to the Mediterranean in September–October 1941
Galileo Ferraris 9 May 19411 patrol, no ships sunksunk by HMS Lamerton on 25 October 1941
Perla 19 May 1941coastal submarine, no patrols under Betasomreturned to the Mediterranean in September–October 1941

In 1941, it was decided to return some of the boats to the Mediterranean. Perla, Guglielmotti, Brin, Argo, Velella, Dandolo, Emo, Otaria, Mocenigo, and Veniero made the passage. Glauco also made the return voyage but was sunk by the British Royal Navy off Cape Spartel.

The submarine cruiser Ammiraglio Cagni was dispatched from the Mediterranean to patrol off South Africa in October 1942. On completion she returned to Bordeaux, transferring to BETASOM in February 1943. She was converted there for transport to the Far East but was overtaken by the Italian Armistice in September 1943 and was interned at Durban.

Submarine cruiser, transferred to BETASOM [17]
NameArrival dateSuccessesFate/Notes
Ammiraglio Cagni 20 Feb 19432 ships, totalling 5,840 GRTconverted to transport submarine, interned at armistice

Post-World War II

The submarine pens have proved to be infeasible to demolish due to their massive reinforced construction which had been designed to withstand aerial bombardment. As of 2010, after conversion several years previously, approximately 12,000 m2 (130,000 sq ft) of the 42,000 m2 (450,000 sq ft) building are open to the public as a cultural centre for the performing arts, exhibitions, and evening events. [19]

Notes

  1. "B" (for Bordeaux) is rendered with BETA and SOM is an abbreviation for sommergibile (plural sommergibili) which is – along with sottomarino – an Italian word for submarine

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References

  1. D'Adamo, Cristiano (1996–2008). "BETASOM". REGIAMARINA. Retrieved 13 March 2012.
  2. The Atlantic Base
  3. 1 2 Ireland, Bernard (2003). Battle of the Atlantic. Barnsley, UK: Pen & Sword Books. pp. 51–52. ISBN   1-84415-001-1.
  4. 1 2 3 4 The Italian submarine force in the battle of the Atlantic
  5. 1 2 Van der Vat, Dan (2001). The Atlantic Campaign. Birlinn. p. 216. ISBN   1841581240.
  6. Thirty two submarines operated in the Atlantic for the Italian Navy and sank 109 Allied ships for a total of 593,864 tons.
  7. USN (RET.), Captain John F. O'Connell (2011-08-18). Submarine Operational Effectiveness in the 20th Century: Part Two (1939 - 1945). iUniverse. ISBN   9781462042616.
  8. 1 2 3 4 5 6 7 Giorgerini, Giorgio (2002). Uomini sul fondo : storia del sommergibilismo italiano dalle origini a oggi[Men on the bottom: the story of Italian submersibles from the beginning to today] (in Italian). Milano: Mondadori. ISBN   9788804505372.
  9. Clay Blair, Hitler's U-boat War: The Hunters, 1939-1942, p.740
  10. The US Navy's most successful submarine, USS Tang, sank 116,454 GRT, while HMS Upholder, the Royal Navy's most successful submarine, sank 93,031 GRT of shipping.
  11. Piekałkiewicz, Janusz. Sea War: 1939-1945. Blandford Press, London - New York, 1987, pg. 106, ISBN   0-7137-1665-7
  12. D'Adamo, Cristiano (1996–2007). "The Bombardments of Bordeaux and the Italian submarine base "BETASOM"". Regiamarina. Archived from the original on 7 February 2009. Retrieved 7 Jan 2009.
  13. Foot, M.R.D. (1966). SOE in France. History of the Second World War. HMSO. pp. 157–159.
  14. Rosselli, Alberto. "Italian Submarines and Surface Vessels in the Far East: 1940-1945". Comando Supremo. Archived from the original on 3 February 2009. Retrieved 7 Jan 2009.
  15. Stamps of the Italian Socialist Republic - The Atlantic Base
  16. "Regia Marina Italiana". Cristiano D'Adamo. Retrieved 2012-07-31.
  17. 1 2 3 Clay Blair, Hitler’s U-Boat War Vol I (1996) App 8 (p739). ISBN   0-304-35260-8
  18. Blair lists 13 ships totalling 90,415 GRT only for BETASOM, with the 4 ships totalling 29,828 GRT sunk in the Indian Ocean counted separately
  19. "Bordeaux: Base sous-marine" . Retrieved 5 January 2019.