View source for French submarine Watt

{{Short description|Warship}}
{|{{Infobox ship begin}}
{{Infobox ship image
|Ship image=Sous Marin MONGE 1918.jpg
|Ship caption=A postcard of [[sister ship]] {{ship|French submarine|Monge|1908|2}} underway before 1915
}}
{{Infobox ship career
|Hide header=
|Ship country=France
|Ship flag={{Shipboxflag|France|naval}}
|Ship name=''Watt''
|Ship namesake=[[James Watt]] (1736–1819), [[Scotland|Scottish]] [[Invention|inventor]], [[mechanical engineer]], and [[chemist]]
|Ship ordered=26&nbsp;August&nbsp;1905 or 19&nbsp;October&nbsp;1906 (see&nbsp;text)
|Ship builder=[[Arsenal de Rochefort]], [[Rochefort, Charente-Maritime|Rochefort]],&nbsp;[[France]]
|Ship original cost=
|Ship laid down=19 October 1906
|Ship launched=18 June 1909
|Ship christened=
|Ship completed=1910
|Ship commissioned=15 March 1910
|Ship struck=1 December 1919
|Ship identification=[[Pennant number]]: Q75
|Ship fate=*Condemned 16 October 1919
*Sold for scrapping 11&nbsp;June&nbsp;1921
|Ship notes=
}}
{{Infobox ship characteristics
|Hide header=
|Header caption=(as built)
|Ship type=[[Submarine]]
|Ship displacement=*{{Convert|404|t|LT|0|abbr=on}} (surfaced)
* {{Convert|553|t|LT|0|abbr=on}} (submerged)
|Ship length={{convert|51.12|m|ftin|abbr=on}} ([[o/a]])
|Ship beam={{convert|4.96|m|ftin|abbr=on}}
|Ship draft={{convert|3.15|m|ftin|abbr=on}}
|Ship power=*{{convert|700|PS|kW bhp|lk=on|abbr=on}}  (steam)
* 2 × [[du Temple boiler]]s
* {{convert|460|PS|kW bhp|abbr=on}}  (electric motors)
|Ship propulsion=*2 × shafts; 2 × [[Marine steam engine#Triple or multiple expansion|triple-expansion steam engines]]
* 2 × [[electric motor]]s
|Ship speed=*{{convert|12|kn|lk=in}} (surfaced)
* {{convert|8|kn}} (submerged)
|Ship range=*{{convert|1000|nmi|abbr=on|lk=in}} at {{convert|8.5|kn}} (surfaced)
* {{convert|27|nmi|abbr=on}} at {{convert|5|kn}} (submerged)
|Ship test depth=
|Ship complement=2 officers and 23 crewmen
|Ship armament=6 × external {{convert|450|mm|in|1|abbr=on}} [[torpedo launcher]]s (4 × fixed, 2 × [[Drzewiecki drop collar]]s)
}}
|}
'''''Watt''''' (Q75) was one of 18 {{sclass|Pluviôse|submarine}}s built for the [[French Navy]] ({{lang|fr|Marine Nationale}}) in the first decade of the 20th century. Commissioned in 1910, she served during [[World War I]] and was stricken in 1919.

==Design and description==
The ''Pluviôse'' class were built as part of the French Navy's 1905 building program to a [[Submarine hull|double-hull]] design by [[Maxime Laubeuf]].<ref name=gg8>Gardiner & Gray, p. 209</ref> The submarines [[Displacement (ship)|displaced]] {{convert|404|t|LT|sp=us|lk=on}} surfaced and {{convert|553|t|LT|sp=us}} submerged. They had an [[length overall|overall length]] of {{convert|51.12|m|ftin|sp=us}}, a [[beam (nautical)|beam]] of {{convert|4.96|m|ftin|sp=us}}, and a [[draft (hull)|draft]] of {{convert|3.15|m|ftin|sp=us}}. Their crew numbered two officers and 23 enlisted men.<ref>Garier 1998, pp. 51, 54, 56, 65</ref>

For surface running, the submarines were powered by two {{convert|350|PS|bhp kW|lk=on|0|adj=on}} [[Marine steam engine#Triple or multiple expansion|triple-expansion steam engines]], each driving one [[propeller shaft]] using steam provided by two [[Du Temple boiler]]s. When submerged, each propeller was driven by a {{convert|230|PS|bhp kW|0|adj=on}} [[electric motor]].<ref>Garier 1998, pp. 56–59</ref> On the surface they were designed to reach a maximum speed of {{convert|12|kn|lk=in}} and {{convert|8|kn}} underwater.<ref name=gg8/> The submarines had a surface endurance of {{convert|865|nmi|lk=in}} at {{convert|11.6|kn}} and a submerged endurance of {{cvt|70|nmi}} at {{convert|2.8|kn}}.<ref>Garier 1998, p. 67</ref>

The first six submarines completed were armed with a single {{convert|450|mm|in|1|adj=on|sp=us}} internal bow [[torpedo tube]], but this was deleted from the rest of the submarines after an accident involving their [[sister ship]] {{ship|French submarine|Fresnel|1908|2}} in 1909. All of the submarines were fitted with six {{convert|450|mm|in|1|adj=on|sp=us}} external [[torpedo launcher]]s; the pair firing forward were fixed outwards at an angle of seven degrees and the rear pair had an angle of five degrees. Following a ministerial order on 22 February 1910, the aft tubes were reversed so they too fired forward, but at an angle of eight degrees. The other launchers were a rotating pair of [[Drzewiecki drop collar]]s in a single mount positioned on top of the [[Hull (ship)|hull]] at the [[stern]]. They could [[Traverse (gunnery)|traverse]] 150 degrees to each side of the submarine. The ''Pluviôse''-class submarines carried eight [[torpedo]]es.<ref>Garier 1998, pp. 59–60</ref>

==Construction and commissioning==
''Watt'', named after the British 18th-century inventor [[James Watt]], was ordered on either 26 August 1905<ref name=sousmarinesdisparus>[http://sous.marins.disparus.free.fr/index.php/sous-marins/103-watt?showall=1 Sous-Marins Français Disparus & Accidents: Sous-Marin Watt (in French) Accessed 29 April 2023]</ref> or 19 October 1906<ref name=garierp49>Garier, p. 49</ref> (according to different sources) from the [[Arsenal de Rochefort]] in [[Rochefort, Charente-Maritime|Rochefort]],&nbsp;[[France]].<ref name=sousmarinesdisparus/><ref name=garierp49/> Her [[keel]] was [[Keel-laying|laid down]] on 19 October 1906.<ref name=sousmarinesdisparus/><ref>Couhat, p. 140</ref> She was [[Ceremonial ship launching|launched]] on 18 June 1909.  During her builder's [[sea trials]], she suffered [[steam engine]] damage on 21 December 1909 that forced her to interrupt her trials and return to port.<ref name=sousmarinesdisparus/>

''Watt'' was completed in 1910.<ref name=sousmarinesdisparus/> Her pre-acceptance trials were interrupted on 8 March 1910 when the [[Norway|Norwegian]] [[Steamship|steamer]] {{SS|Torgnay}} collided with and damaged her.<ref name=sousmarinesdisparus/> She was [[Ship commissioning|commissioned]] on 15 March 1910<ref name=sousmarinesdisparus/><ref>Garier 1998, p. 50</ref> with the [[pennant number]] Q75.<ref name=sousmarinesdisparus/>

==Service history==
===Pre-World War I===
''Watt'' struck either a [[Breakwater (structure)|breakwater]], [[jetty]], [[Mole (architecture)|mole]], or [[seawall]]<!--ambiguous translation of "digue" from French could mean breakwater, jetty, mole, or sea wall--> as she returned to her anchorage on 3 December 1910. She suffered [[Bow (ship)|bow]] damage with an estimated repair time of two months.<ref name=sousmarinesdisparus/>

By 1911, ''Watt'' was based at [[Brest, France|Brest]], France.<ref name=sousmarinesdisparus/> She was moored at a [[wharf]] at the [[Brest Arsenal]] on 10 June 1913 when the submarine {{ship|French submarine|Thermidor||2}} collided with her.<ref name=sousmarinesdisparus/> Both submarines suffered damage, particularly ''Watt'', which sustained a gash over {{convert|40|cm|in}} in length in her external [[Port and starboard|port]] [[ballast tank]] that required a substantial period of time to repair.<ref name=sousmarinesdisparus/>

===World War I===
[[World War I]] broke out on 28 July 1914 with [[Austria-Hungary]]′s declaration of war on [[Serbia]], and France entered the war on the side of the [[Allies of World War I|Allies]] when the [[German Empire]] declared war on France on 3 August 1914. After the declaration of war, ''Watt'' conducted patrols in the [[English Channel]], and from September 1914 to June 1915 she was based in [[England]] at [[Portsmouth]] as part of defense agreements between France and the [[United Kingdom]].<ref name=sousmarinesdisparus/> From 14 to 22 September 1915 she operated in the [[Bay of Biscay]]<ref name=sousmarinesdisparus/> between Brest and [[La Pallice]].

By 17 January 1917, ''Watt'' was serving in the [[Mediterranean Sea]], based at [[Bizerte]] in [[French protectorate of Tunisia|Tunisia]]. She patrolled off [[French Algeria|Algeria]] and in the [[Strait of Sicily]].<ref name=sousmarinesdisparus/>

''Watt'' was the target of a [[friendly fire]] incident in 1918. At daybreak on 26 March 1918, she was on the surface in the Mediterranean Sea north of the [[Galite Islands]] off the coast of Tunisia when she crossed paths with an Allied [[convoy]] en route from [[Gibraltar]] to [[Bizerte]], Tunisia, consisting of 15 ships escorted by the British [[Royal Navy]] [[warship]] {{HMS|Jeannette II}}, the [[United States Navy]] armed [[yacht]] {{USS|Wenonah|SP-165|6}}, the U.S. Navy [[gunboat]] {{USS|Nashville|PG-7|6}}, and two French [[naval trawler]]s. An enemy submarine had [[torpedo]]ed one of the convoy′s ships the during the previous night and the convoy′s escorts had just investigated an erroneous sighting of a purported submarine to [[Port and starboard|port]] when ''Jeannette II'' sighted ''Watt'' ahead of the convoy. She assumed ''Watt'' was an enemy submarine. ''Watt'' submerged, and ''Jeannette II'' attacked her, dropping two [[depth charge]]s and forcing her back to the surface. The British armed [[merchant ship]] {{SS|Frank Parish}}, and according to one source<ref name=proceedingsmistakenattacks>[https://www.usni.org/magazines/proceedings/1934/december/mistaken-attacks-world-war Doughty, Leonard, Jr., Lieutenant Commander, "Mistaken Attacks in the World War," ''Proceedings'', October 1934.]</ref> several other ships in the convoy as well, then opened fire on ''Watt'', as did ''Wenonah'' at a range of {{convert|1,000|yd|sigfig=2}}. ''Wenonah'' fired twelve rounds, inflicting considerable damage on ''Watt'', killing her [[commanding officer]] and wounding five others. The convoy overtook ''Watt'', and ''Wenonah'' ceased fire to avoid hitting ships in the convoy. After members of ''Watt''′s crew came on deck and waved their arms, the convoy′s escorts identified her as friendly. ''Jeannette II'' and one of the trawlers went to ''Watt''′s assistance; ''Jeannette II'' took off her wounded, one of whom, a [[Seaman (rank)|seaman]], later died of his wounds, and the trawler escorted ''Watt'' into port.<ref name=sousmarinesdisparus/><ref name=proceedingsmistakenattacks/>

A joint court of inquiry with one American, two British, and two French naval officers as members took place at Gibraltar and found no one to blame for the incident. Another joint court of inquiry consisting of two British and two French naval officers took place at Bizerte, and also found no one to blame, concluding that ''Watt'' had disobeyed orders governing submarines operating in the area.<ref name=proceedingsmistakenattacks/>

==Final disposition==

''Watt'' was condemned on 16 October 1919 and stricken from the navy list on 1 December 1919.<ref name=sousmarinesdisparus/> She was sold at Bizerte to ''[[Monsieur]]'' Crispin for 28,236 [[French franc]]s on 11 June 1921<ref name=sousmarinesdisparus/> and subsequently scrapped.

==References==
===Citations===
{{reflist|30em}}

===Bibliography===
*{{cite book|last=Balincourt|first=Raoul de |title=Les Flottes de combat en 1917|publisher=Augustin Challamel|year=1917|language=fr}}
*{{cite book|last=Couhat|first=Jean Labayle|title=French Warships of World War I|year=1974|publisher=Ian Allan|location=London|isbn=0-7110-0445-5}}
*{{cite book|last1=Gardiner|first1=Robert|last2=Gray|first2=Randal|title=Conway's All The World's Fighting Ships 1906–1921|year=1985|publisher=Conway Maritime Press|location=London|isbn=0-85177-245-5|name-list-style=amp}}
*{{cite book|last=Garier|first=Gérard|title=A l'épreuve de la Grande Guerre|series=L'odyssée technique et humaine du sous-marin en France|volume=3–2|year=2002|publisher=Marines édition|location=Bourg-en-Bresse, France|isbn=2-909675-81-5|language=French}}
*{{cite book|last=Garier|first=Gérard|title=Des ''Émeraude'' (1905-1906) au ''Charles Brun'' (1908–1933)|series=L'odyssée technique et humaine du sous-marin en France|volume=2|year=1998|publisher=Marines édition|location=Bourg-en-Bresse, France|isbn=2-909675-34-3|language=French}}
* {{Cite book|language=fr|first1=Gérard|last1=Garier|title=L'odyssée technique et humaine du sous-marin en France, Tome 2: Des "Emeraudes" (1905-1906) au "Charles Brun" (1908-1913)|location=Nantes|publisher=Marines éd|year=1998|isbn=978-2-909675-34-3}}
* {{Cite book|language=fr|first1=Jean|last1=Guiglini|title=Les marques particulières des navires de guerre français, 1900-1950|location=Vincennes|publisher=Service historique de la marine|year=2003|isbn=978-2-11-091847-5}} 
* {{cite book|last=Roche|first=Jean-Michel|title=Dictionnaire des bâtiments de la flotte de guerre française de Colbert à nos jours, Tome II, 1870-2006|publisher=Imp. Rezotel-Maury Millau|year=2005|language=fr}}
* {{cite book|last1=Vichot|first1=Jacques|last2=Boucheix|first2=Pierre|last3=Michéa|first3=Hubert|title=Répertoire des navires de guerre français, revised by Hubert Michéa|publisher=AAMM|year=2003|language=fr}}

==External links==
* {{Cite web|language=fr|title=Pages 14-18|url=http://pages14-18.mesdiscussions.net/pages1418/Forum-Pages-d-Histoire-aviation-marine/marine-1914-1918/watt-marin-sujet_647_1.htm|website=Watt|access-date=3 February 2012|archive-date=20 November 2015|archive-url=https://web.archive.org/web/20151120140935/http://pages14-18.mesdiscussions.net/pages1418/Forum-Pages-d-Histoire-aviation-marine/marine-1914-1918/watt-marin-sujet_647_1.htm|url-status=dead}}

{{Pluviôse class submarines}}
{{1909 shipwrecks}}
{{1910 shipwrecks}}
{{1913 shipwrecks}}
{{March 1918 shipwrecks}}

{{DEFAULTSORT:Watt}}
[[Category:Pluviôse-class submarines]]
[[Category:World War I submarines of France]]
[[Category:1909 ships]]
[[Category:Maritime incidents in 1909]]
[[Category:Maritime incidents in 1910]]
[[Category:Maritime incidents in 1913]]
[[Category:Maritime incidents in 1918]]
[[Category:Friendly fire incidents of World War I]]