View source for Italian submarine Iride

{{Short description|Submarine of the Royal Italian Navy}}
{|{{Infobox ship begin}}
{{Infobox ship image
|Ship image= [[File:Smg Iride.jpg|300px|RIN Iride]]
|Ship caption=
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{{Infobox ship career
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|Ship country= [[Kingdom of Italy]]
|Ship flag={{shipboxflag|Kingdom of Italy|naval}}
|Ship name= ''Iride''
|Ship namesake= 
|Ship ordered= 
|Ship awarded=
|Ship builder=[[Oto Melara|OTO]], [[Muggiano]]
|Ship original cost=
|Ship laid down= 3 September 1935
|Ship launched= 30 July 1936 
|Ship completed= 
|Ship acquired=
|Ship commissioned= 6 November 1936
|Ship in service=
|Ship fate= Sunk, 22 August 1940
|Ship notes=
|Ship badge=
}}
{{Infobox ship characteristics
|Hide header=
|Header caption= 
|Ship class={{sclass|Perla|submarine}}
|Ship displacement=* {{convert|622.57|t|LT|0}} standard
* {{convert|696.0|t|LT|0}} normal (surfaced)
* {{convert|852.5|t|LT|0}} normal (submerged)
|Ship length={{convert|60.18|m|ftin|abbr=on}}<ref name=ISI/>
|Ship beam={{convert|6.454|m|ftin|abbr=on}}<ref name=ISI/>
|Ship draft={{convert|4.724|m|ftin|abbr=on}}<ref name=ISI/>
|Ship power=* {{convert|1200|bhp|lk=in|abbr=on}} (diesels)
* {{convert|800|hp|abbr=on}} (electric motors)
|Ship propulsion=* [[Diesel-electric]]
* 2 × [[Fiat S.p.A.|FIAT]] [[diesel engine]]s
* 2 × [[Cantieri Riuniti dell'Adriatico|CRDA]] electric engines
|Ship speed=* {{convert|14|kn|lk=in}} surfaced<ref name=ISI/>
* {{convert|7.5|kn}} submerged<ref name=ISI/>
|Ship range=* {{convert|5200|nmi|abbr=on|lk=in}} at {{convert|8|kn}} surfaced<ref name=ISI/>
* {{convert|74|nmi|abbr=on}} at {{convert|4|kn}} submerged<ref name=ISI/>
|Ship endurance=
|Ship test depth={{convert|80|m|ft|abbr=on}}<ref name=ISI/>
|Ship complement=44 (4 officers + 40 non-officers and sailors)
|Ship armament=* 6 × {{convert|533|mm|in|0|abbr=on}} [[torpedo tube]]s (4 bow, 2 stern)<ref name=ISI/>
* 1 × [[Škoda 10 cm K10#OTO 100.2F47 History|{{convert|100|mm|in|abbr=on|0}} / 47&nbsp;caliber]] [[deck gun]]<ref name=ISI/>
* 2 × 1 – [[Breda Model 1931 Machine Gun|{{convert|13.2|mm|in|abbr=on}}]] [[anti-aircraft gun]]s<ref name=ISI/>
|Ship notes=
}}
|}

'''Italian submarine ''Iride''''' was a {{sclass|Perla|submarine|2}} built for the [[Royal Italian Navy]] (''Regia Marina'') during the 1930s. Originally, she was named ''Iris'' until July 1936, but was renamed shortly before her launch.

==Design and description==
The ''Perla''-class submarines were essentially repeats of the preceding {{sclass|Sirena|submarine|4}}. The modifications that were made compared to the boats of the previous series were mostly of upgrade nature. Among them were enlargement of the false tower at the top, more modern engines, installation of a radiogoniometer that could be controlled from inside the ship. Improvements and the installation of new air conditioning equipment meant a slight increase in displacement, and increase in the fuel stowage also increased the autonomy of these boats compared to the previous series.<ref name=ISI1>Pollina, p. 155</ref> Their designed full load [[Displacement (ship)|displacement]] was {{convert|695|t|LT|sp=us}} surfaced and {{convert|855|t|LT|sp=us}} submerged, but varied somewhat depending on the boat and the builder. The submarines were {{convert|197|ft|6|in|m|sp=us}} long, had a [[beam (nautical)|beam]] of {{convert|21|ft|m|sp=us}} and a [[draft (hull)|draft]] of {{convert|15|ft|m|sp=us}} to {{convert|15|ft|5|in|m|sp=us}}.<ref name=b4>Bagnasco, p. 153</ref><ref name=ISI>Pollina, pp. 152–153</ref>

For surface running, the boats were powered by two [[diesel engine]]s, each driving one [[propeller shaft]] with overall power of {{convert|675|-|750|hp|abbr=on|lk=in|0|adj=on}}.<ref name=b4/> When submerged each propeller was driven by a {{convert|400|hp|0|adj=on}} [[electric motor]]. They could reach {{convert|14|kn|lk=in}} on the surface and {{convert|7.5|kn}} underwater. On the surface, the ''Perla'' class had a range of {{convert|5200|nmi|lk=in}} at {{convert|8|kn}}, submerged, they had a range of {{convert|74|nmi|abbr=on}} at {{convert|4|kn}}.<ref name=b4>Bagnasco, p. 153</ref><ref name=ISI/>

The boats were armed with six internal {{convert|53.3|cm|in|1|abbr=on|sp=us}} [[torpedo tube]]s, four in the bow and two in the stern. One reload torpedo was carried for each tube, for a total of twelve. They were also armed with one [[Škoda 10 cm K10#OTO 100.2F47 History|{{convert|100|mm|in|abbr=on|0}}]] [[deck gun]] for combat on the surface. The light anti-aircraft armament consisted of one or two pairs of [[Breda Model 1931 Machine Gun|{{convert|13.2|mm|in|abbr=on}}]]  machine guns.<ref name=ISI/>

In July 1940 ''Iride'' was retained by [[Decima Flottiglia MAS]] to be converted into a submarine to carry Siluro a Lenta Corsa (SLC) [[manned torpedo]]es.  She was fitted with four SLC units, two placed side by side aft, and two on her bow, the submarine's deck gun was also removed to accommodate SLC units and the tower was modified to better adapt for the new role. These SLC cylinders were able to withstand depths up to 30 meters.<ref name=gr>Greene, pp. 50–51</ref>

==Construction and career==
''Iride'' was built by [[Oto Melara|OTO]] at their shipyard in [[Muggiano]], laid on 3 September 1935, [[Ship naming and launching|launched]] on 30 July 1936 and completed on 6 November 1936.<ref name=ISI/>

After delivery, ''Iride'' was assigned to the 12th Squadron (I Submarine Group) based at [[La Spezia]]. After a brief training, in 1937 and 1938 she carried out long endurance cruises in the [[Dodecanese]], [[Mediterranean Sea]] and around [[North Africa]]n coast.

''Iride'' secretly participated in the [[Spanish Civil War]], being a part of two incidents that strained Italo-British relations. She carried out a mission from 24 August to 5 September 1937 under the command of [[Junio Valerio Borghese]]. On 26 August, ''Iride'' arrived at her designated area between [[Ibiza]] and [[Cape San Antonio, Spain|Cape San Antonio]]. During the patrol she attempted attacks eight times, but only fired on two of those. In the evening of 29 August, she sighted a cargo ship heading towards [[Valencia]], and attacked it twice, second time from {{convert|600|m|ft|0|abbr=on}}, and both were unsuccessful.<ref name=gr1>Greene, pp. 16–18</ref> At 20:45 on 30 August 1937, while traveling on the surface, she sighted British destroyer {{HMS|Havock|H43|6}} steaming from [[Valencia]] to [[Gibraltar]], and mistaking it for a Spanish naval ship of the {{sclass|Churruca|destroyer|4}}, launched a 450&nbsp;mm torpedo from {{convert|700|m|ft|abbr=on|0}} at 20:52. ''Havock'' managed to avoid the torpedo with a sharp turn to the starboard, and then went on to search for the submarine using her sonar. However, the sonar showed a different position than where the submarine was sighted, and ''Havock'' proceeded to launch [[depth charge]]s on the sonar location. British destroyers {{HMS|Active|H14|6}}, {{HMS|Hyperion|H97|6}} and {{HMS|Hotspur|H01|6}}, and a cruiser {{HMS|Galatea|71|6}} joined in, and continued the attack for nine hours. ''Iride'' hiding at a great depth managed to survive and did not sustain any serious damage.<ref name=gr1/> During the attack, she did accidentally surface and was identified by the British as an Italian submarine.<ref>Frank, p. 96</ref>

Following the incident, in September 1937 the [[Nyon Conference]] was called by [[France]] and [[Great Britain]] to address the "underwater piracy" conducted against merchant traffic in the [[Mediterranean Sea]]. On 14 September, an agreement was signed establishing British and French patrol zones around [[Spain]] (with a total of 60 destroyers and aircraft employed) to counteract aggressive behavior by submarines. [[Kingdom of Italy|Italy]] was not directly accused, but had to comply with the agreement and suspend the underwater operations.

Under pressure from [[Francisco Franco|Franco's]] regime, Italy decided to transfer four more submarines (in addition to {{ship|Italian submarine|Archimede|1933|2}} and {{ship|Italian submarine|Evangelista Torricelli|1934|2}} already being operated by the [[Falangist]]s) to the [[Spanish Legion]] (''Legión Española or Tercio de Extranjeros''). ''Iride'' was one of the four boats chosen for the transfer. On 23 September 1937 ''Iride'' arrived at [[Soller]] on [[Mallorca]]. She was placed under the direct command of Spanish Admiral Francisco Moreno, was renamed ''Gonzalez Lopez'' and assigned pennant number L3. However, ''Iride'' retained her commander (captain [[Junio Valerio Borghese]]), senior officers and Italian crew, but they had to wear Spanish uniforms and insignia.

The other three Italian submarines transferred to Tercio were {{ship|Italian submarine|Onice||2}} (''Aguilar Tablada''), {{ship|Italian submarine|Galileo Galilei||2}} (''General Mola II'') and {{ship|Italian submarine|Galileo Ferraris|1934|2}} (''General Sanjurjo II''). All four were based at Soller. During her "legionary" career ''Iride'' carried out two missions, one in October 1937, leaving on 24 October and returning eight days later, and another one in January 1938, leaving on 14 January 1938 and finishing nine days later.<ref name=gr2>Greene, pp. 21–23</ref> During her second mission, ''Iride'' again patrolled along the Spanish coast, and attempted an attack twice, on 19 January and 22 January 1938, by launching four torpedoes, but both attacks were unsuccessful.<ref name=gr2/> In February 1938 she returned home, as Italy withdrew their submarines from Spanish service due to international pressure. ''Iride'' was assigned to 14th Squadron (I Submarine Group) based at [[La Spezia]].

In 1938 and 1939 she spent time at the [[Red Sea]] base of [[Massawa]] together with {{ship|Italian submarine|Onice||2}} and {{ship|Italian submarine|Berillo||2}}. She returned to Italy in 1939 and was assigned to 13th Squadron (I Submarine Group) based at La Spezia.

After Italy's entrance into the war, ''Iride'' under command of captain Francesco Brunetti on 14 June 1940 was deployed on her first war mission to patrol off [[Toulon]]. She returned to La Spezia after a few days without sighting any enemy vessels. During her second mission, on 23 June, ''Iride'' while patrolling in the [[Gulf of Lion]], sighted a ship travelling to [[Marseille]]. She launched two torpedoes but failed to hit the target.

In July 1940 ''Iride'' was chosen for conversion to SLC submarine to attempt the first attack against British naval base in [[Alexandria]]. Work was finished in early August, and on 12 August 1940 ''Iride'' departed La Spezia and after a brief stop in [[Trapani]] on 16 August, reached the Bay of Menelao in the [[Gulf of Bomba]] of the coast of [[Cyrenaica]] together with torpedo boat {{ship|Italian torpedo boat|Calipso|1938|2}}, which carried the SLC crew, and the support ship ''Monte Gargano''.<ref name=gr3>Greene, pp. 52–54</ref>
 
During the night of 21 August the SLCs were loaded onto the submarine's deck, and a test navigation were to be carried out the next morning.<ref name=gr3/> A reconnaissance plane flew by in the morning of 22 August 1940 and spotted Italian ships in the bay. Around noon three [[Fairey Swordfish]] [[torpedo bomber]]s from the aircraft carrier {{HMS|Eagle|1918|6}} that were temporarily based at Maaten Baggush airfield in the western desert were launched and attacked ''Iride'' and the other ships while they were performing a diving test with four human torpedoes. One of the aircraft released a torpedo from about {{convert|200|m|ft|0}} and after a few seconds ''Iride'' got hit amidships, broke in two, and quickly sank in 15 meters of water, followed shortly by ''Monte Gargano'' which was also hit by a torpedo.<ref name=gr3/>

The flight leader, Captain Oliver Patch,<ref>[http://www.flyingmarines.com/Biographies/1931-1940/Patch.htm Flying Marines – Oliver Patch]</ref> Royal Marines, sank ''Iride'', while John Wellham and Lieutenant Neville Cheesman attacked the other two ships. A few crew members were rescued with the support of the human torpedo operators; most died in the sinking. John Wellham, low on fuel and wounded, returned to his desert base and was awarded the [[Distinguished Service Cross (United Kingdom)|Distinguished Service Cross]].<ref>{{cite web |title=Obituary: Lieutenant-Commander John Wellham |date=2006-07-06 |website=[[The Guardian]] |archive-url=https://web.archive.org/web/20220702212627/https://www.theguardian.com/news/2006/jul/06/guardianobituaries.secondworldwar |archive-date=2022-07-02 |url-status=live |url=https://www.theguardian.com/news/2006/jul/06/guardianobituaries.secondworldwar}}</ref> Patch received the [[Distinguished Service Order]], while Cheesman, Sub-Lieutenant [[Fred Stovin-Bradford|Frederick Stovin-Bradford]] and Acting Sub-Lieutenant Gordon Woodley also received the Distinguished Service Cross, and Petty Officer Alfred Marsh the [[Distinguished Service Medal (United Kingdom)|Distinguished Service Medal]].<ref>{{London Gazette|issue=35041|supp=y|page=262|date=10 January 1941}}</ref> Patch and Wellham would later fly in the [[Battle of Taranto|attack on Italian fleet at Taranto harbour]].<ref>{{London Gazette|issue=35166|supp=y|pages=2869–2870|date=16 May 1941}}</ref>

While examining the wreckage, operators discovered that two non-commissioned officers and seven sailors were still alive trapped in one of the aft compartments of the submarine.<ref name=gr3/>  The situation was critical: the compartment was slowly flooding and the escape door was jammed distorted by the explosion. After several hours of work, all seven men managed to get to the surface with the help of divers, two men died because they did not follow the instructions. Of the seven survivors two sailors died later of embolism.<ref name=gr3/> Overall, ''Iride'' lost 35 men (3 officers, 9 non-officers and 23 sailors) with 17 survivors. All four SLCs were recovered with minor damage, and brought back to La Spezia by ''Calipso''. The first assault operation had ended in disaster.

== Notes==
{{reflist|30em}}

==References==

* {{cite book|last=Bagnasco |first=Erminio |title=Submarines of World War Two |year=1977 |publisher=Naval Institute Press |location=Annapolis, Maryland |isbn=0-87021-962-6}} 
* {{cite book|title=Conway's All the World's Fighting Ships 1922–1946|editor1-last=Chesneau|editor1-first=Roger|publisher=Conway Maritime Press|location=Greenwich, UK|year=1980|isbn=0-85177-146-7}}
* {{Cite book|last=Costello & Hughes|oclc=464381083 | title=The Battle of the Atlantic |year=1977|publisher = Collins }}
*{{cite journal |last1=Frank |first1=Willard C. Jr. |title=Question 12/88 |journal=Warship International |date=1989 |volume=XXVI |issue=1 |pages=95–97 |issn=0043-0374}}
* {{cite book|last=Giorgerini|first=Giorgio|title=Uomini sul fondo. Storia del sommergibilismo italiano dalle origini ad oggi|publisher=Mondadori|year=2002|edition=Second|isbn=88-04-50537-0}}
* {{cite book|last=Greene|first=Jack|title=The Black Prince And The Sea Devils: The Story Of Valerio Borghese And The Elite Units Of The Decima Mas|publisher=Da Capo Press|year=2004|edition=First|isbn=0-306-81311-4}}
* {{cite book|last=Pollina|first=Paolo|title=I Sommergibili Italiani 1895–1962|publisher=SMM|year=1963|location=Rome, Italy}}
* {{cite book|last=Rohwer|first=Jürgen|title=Chronology of the War at Sea 1939–1945: The Naval History of World War Two|publisher=Naval Institute Press|location=Annapolis, Maryland|year=2005|edition=Third Revised|isbn=1-59114-119-2|author-link=Jürgen Rohwer}}

{{Portal bar|Italy|Engineering}}
{{Perla-class submarine}}
{{August 1940 shipwrecks}}
{{Use dmy dates|date=August 2014}}
{{coord missing|Mediterranean}}

{{DEFAULTSORT:Iride}}
[[Category:Perla-class submarines]]
[[Category:World War II submarines of Italy]]
[[Category:Lost submarines of Italy]]
[[Category:Maritime incidents in August 1940]]
[[Category:World War II shipwrecks in the Mediterranean Sea]]
[[Category:1936 ships]]
[[Category:Ships built in La Spezia]]
[[Category:Ships built by OTO Melara]]
[[Category:Military units and formations of Italy in the Spanish Civil War]]
[[Category:Submarines sunk by aircraft]]
[[Category:Ships sunk by British aircraft]]