Editing Gato-class submarine (section)

=== World War II ===
[[File:Buyo Maru sinking.jpg|thumb|left|Periscope photograph of Japanese merchant ship sinking]]
The ''Gato'' boats were authorized in appropriations for Fiscal Year 1941, as part of President [[Franklin Roosevelt]]'s proclamation of "limited emergency" in September 1939.<ref>{{harvnb|O'Kane|1987|p=2}}</ref> The first boat [[Keel laying|laid down]] was actually {{USS|Drum|SS-228|6}} at [[Portsmouth Naval Shipyard]] on 11 September 1940. She was [[Ship commissioning|commissioned]] on 1 November 1941, and was the only ''Gato''-class ship in commission when the war started. ''Gato'' herself was laid down on 5 October 1940 by the Electric Boat Company at [[Groton, Connecticut]], and commissioned 31 December 1941.<ref>{{harvnb|Alden|1979|pp=252–254}}</ref> Due to their large construction capacity, more than half (41) of the class was built at Electric Boat facilities; three new slipways were added to the north yard and four slipways were added to the south yard to accommodate their production. In addition, the government purchased an old foundry downstream from the main yard, constructed 10 slipways, and turned the yard over to Electric Boat. Called the [[Victory Yard]], it became an integral part of Electric Boat operations.<ref>{{harvnb|Alden|1979|p=78}}</ref> A total of 77 ''Gato''s were built at four different locations (Electric Boat, Manitowoc, Portsmouth, and Mare Island).

All of the ''Gato''s (with one exception, {{USS|Dorado|SS-248|2}}) would eventually fight in the [[Asiatic-Pacific Theater|Pacific Theater of Operations]]. However, in the summer of 1942, six new ''Gato''s were assigned to Submarine Squadron 50 and sent to [[Rosneath, Scotland]], to patrol the [[Bay of Biscay]] and to assist in the [[Operation Torch]] landings in North Africa. All in all, they conducted 27 war patrols, but could not claim any verified sinkings. Considered a waste of valuable resources, in mid-1943, all six ships were recalled and transferred to the Pacific.<ref>{{harvnb|Blair|2001|pp=264–266}}</ref>

Once they began to arrive in theater in large numbers in mid-to-late 1942, the ''Gato''s were in the thick of the fight against the Japanese. Many of these ships racked up impressive war records: {{USS|Flasher|SS-249|2}}, {{USS|Rasher|SS-269|2}}, and {{USS|Barb|SS-220|2}} were second, third, and fourth based on tonnage sunk by U.S. submarines. {{USS|Silversides|SS-236|2}}, ''Flasher'', and {{USS|Wahoo|SS-238|2}} were third, fourth, and seventh place on the list for the number of ships sunk.<ref>{{harvnb|Blair|2001|pp=989–990}}</ref> ''Gato''-class ships sank four Japanese submarines: {{ship|Japanese submarine|I-29||2}}, {{ship|Japanese submarine|I-168||2}}, {{ship|Japanese submarine|I-351||2}}, and {{ship|Japanese submarine|I-42||2}}; while only losing one in exchange, {{USS|Corvina|SS-226|2}} to {{ship|Japanese submarine|I-176||2}}.

Their principal weapon was the steam-powered [[Mark 14 torpedo]] in the early war years, with the electric [[Mark 18 torpedo]] supplementing the Mark 14 in late 1943. Due to a stunted research-and-development phase in the Depression-era 1930s, and in great part due to the arrogance and stubbornness of its designer, the [[Naval Torpedo Station]] Newport under the [[Bureau of Ordnance]], the "wonder weapon" Mark 14 proved to be full of bugs and very unreliable. They tended to run too deep, explode prematurely, run erratically, or fail to detonate. Bowing to pressure from the submariners in the Pacific, the bureau eventually acknowledged the problems in the Mark 14 and largely corrected them by late 1943. The Mark 18 electric torpedo was a hastily copied version of captured [[G7e torpedo|German G7e torpedoes]] and was rushed into service in the fall of 1943. Unfortunately, it also was full of faults, the most dangerous being a tendency to run in a circular pattern and come back at the sub that fired it. Once perfected, both types of torpedoes proved to be reliable and effective weapons, allowing the ''Gato''s and other submarines to sink an enormous amount of Japanese shipping by the end of the war.<ref>{{harvnb|Roscoe|1949|pp=250–263}}</ref>

The ''Gato''s were subjected to numerous exterior configuration changes during their careers, with most of these changes centered on the conning tower fairwater. The large, bulky original configuration proved to be too easy to spot when the boat was surfaced; it needed to be smaller. Secondly, the desire to incorporate new masts for surface- and air-search radars drove changes to the fairwater and periscope shears. Third, additional gun armament was needed, and cutting down the fairwater provided excellent mounting locations for machine guns and antiaircraft cannon.<ref name="Johnston 2024 2–16">{{harvnb|Johnston|2024|pp=2–16}}</ref> The modifications (or mods) to the ''Gato''-class conning tower fairwaters were fairly uniform in nature and they can be grouped together based on what was done when:
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*  Mod 1 – This is the original configuration with the covered navigation bridge, the high bulwark around the aft "cigarette" deck, and with the periscope shears plated over. All the early boats were built with this mod and it lasted until about mid-1942.
*  Mod 2 – Same as mod 1, but with the bulwark around the cigarette deck cut down to reduce the silhouette. This also gave the [[.50 BMG|.50 caliber]] machine gun mounted there a greatly improved [[arc of fire]]. Began to appear in about April 1942.
*  Mod 3 – Same as mod 2, but with the covered navigation bridge on the forward part of the fairwater cut away and the plating around the periscope shears removed. In this configuration, the ''Gato''s now had two excellent positions for the mounting of single [[Bofors 40 mm Automatic Gun L/60|40 mm Bofors]] or twin [[20 mm Oerlikon]] antiaircraft cannon, an improvement over the [[M2 Browning|.50 caliber machine gun]]. This mod started to appear in late 1942 and early 1943.
*  Mod 4 – Same as the mod 3, but with the height of the bridge itself lowered in a last attempt to lessen the silhouette. The lowering of the bridge exposed three I-beams on either side of the periscope shears. These exposed beams gave rise to the nickname "covered wagon boats". Began to appear in early 1944.
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Variations on the above mods included the 1A (shortened navigation bridge), 2A (plating removed from periscope shears), and the 3A and 4A (which moved the SJ radar mast aft of the periscopes).<ref name="Johnston 2024 2–16"/> The conning tower fairwater of ''Flasher'' is preserved in Groton, Connecticut, in the mod 4A configuration, with two single 40&nbsp;mm Bofors mounts.

[[Deck gun]]s varied during the war. Many targets in the [[Pacific War]] were [[sampan]]s or otherwise not worth a torpedo, so the deck gun was an important weapon. Most ships began the war with a [[3"/50 caliber gun|{{convert|3|in|adj=on}} /50 caliber Mk. 17 gun]] (although some ships received older Mk. 6 mounts due to shortages). The {{convert|3|in|adj=on}} gun was the model originally specified for the ''Gato'' class, but war experience led to the removal of [[4"/50 caliber gun|{{convert|4|in|adj=on}}/50 caliber Mk. 9 guns]] from old [[United States S-class submarine|S-class submarine]]s to equip front-line ships. Beginning in late 1943, almost all were refitted with a [[5"/25 caliber gun|{{convert|5|in|adj=on}}/25 caliber Mk. 17 gun]], and some ships had two of these weapons. Additional antiaircraft guns included single 40&nbsp;mm Bofors and twin 20&nbsp;mm Oerlikon mounts, usually one of each.