Japanese submarine I-37: Difference between revisions

'''''I-37''''', originally numbered '''''I-49''''', was a Japanese [[Type B1 submarine]] in service with the [[Imperial Japanese Navy]] during [[World War II]].<ref name=":1">Boyd, Carl & Yoshida, Akikiko (2002). ''The Japanese Submarine Force and World War II''. Annapolis, Maryland: Naval Institute Press. {{ISBN|1-55750-015-0}}.</ref> Commissioned in 1943, she made three war patrols, all in the [[Indian Ocean]], during the last of which her crew committed [[war crimes]] by massacring the survivors of the [[merchant ship]]s she sank. Subsequently, converted into a ''[[kaiten]]'' manned [[suicide attack]] [[torpedo]] carrier, she was sunk during her first ''kaiten'' mission in 1944.

''I-37'' was {{convert|108.7|m|ftin|abbr=off|sp=us}} long and had a [[Beam (nautical)|beam]] of {{convert|9.3|m|ftin|abbr=off|sp=us}} and a [[Draft (hull)|draft]] of {{convert|5.1|m|ftin|abbr=off|sp=us}}. She could dive to {{convert|100|m|ft|0|abbr=off|sp=us}}<ref name=":1" /> She was armed with six internal [[Bow (ship)|bow]] {{convert|53.3|cm|in|0|abbr=on}} [[torpedo tube]]s and carried a total of 17 [[torpedo]]es. ''I-37'' was also armed with a single [[14 cm/40 11th Year Type naval gun|{{convert|140|mm|in|1|abbr=on}}/40]] [[deck gun]] and two single [[Gun mount|mounts]] for [[Type 96 25 mm AT/AA Gun|Type 96]] [[anti-aircraft gun]]s.<ref name=":1" /> Designed as a [[submarine aircraft carrier]], she had a [[hangar]] and an [[aircraft catapult]] and could carry one [[Yokosuka E14Y]]1 ([[World War II Allied names for Japanese aircraft|Allied reporting name]] "Glen") reconnaissance [[floatplane]].

Upon commissioning, ''I-37'' was attached to the [[Kure Naval District]] and assigned to the Kure Submarine [[Squadron (naval)|Squadron]].<ref name=combinedfleetI37/> She passed through the Iyo Nada in the [[Seto Inland Sea]] on 13 March 1943, and on 22 March underwent inspection by the staff of the Kure Submarine Squadron.<ref name=combinedfleetI37/> She participated in [[torpedo]] practice with the submarines {{ship|Japanese submarine|I-38||2}}, {{ship|Japanese submarine|Ro-104||2}}, and {{ship|Japanese submarine|Ro-105||2}} on 26 March.<ref name=combinedfleetI37/> On 1 April 1943, she was reassigned to Submarine [[Division (naval)|Division]] 11 for work-ups<ref name=combinedfleetI37/> and on 2 April she arrived at Kure for repairs to her attack [[periscope]] and retractable [[short-wave radio]] [[Antenna (radio)|antenna]].<ref name=combinedfleetI37/> After the completion of her repairs, she took part during May 1943 in testing in the Seto Inland Sea of the ''Unkato'' cargo container,<ref name=combinedfleetI37/> a {{convert|135|ft|1|adj=on}} submersible container that could carry up to 377 tons of supplies, designed for a one-way trip in which the cargo′scargo's recipients released, recovered, and unloaded it.<ref>{{cite web |url= http://www.combinedfleet.com/I-45.htm |title=IJN Submarine I-45: Tabular Record of Movement |first1=Bob |last1=Hackett |first2=Sander |last2=Kingsepp |work=combinedfleet.com |date=June 1, 2019|access-date=16 September 2020}}</ref> Workers installed a [[Type 22 (radar)|Type 22]] [[radar]] aboard her in May 1943.<ref name=combinedfleetI37/>

With her workups and testing completed, ''I-37'' was reassigned to Submarine Division 14 in [[8th Submarine Squadron (Imperial Japanese Navy)|Submarine Squadron 8]] in the [[6th Fleet (Imperial Japanese Navy)|6th Fleet]] on 23 May 1943.<ref name=combinedfleetI37/> She got underway from Kure on 25 May bound for [[Penang Island|Penang]] in Japanese-occupied [[British Malaya]], which she reached on 4 June 1943.<ref name=combinedfleetI37/>

On 19 June 1943, ''I-37'' hit the 7,176-ton American Liberty ship {{SS|Henry Knox}} — bound from [[Fremantle]], Australia, to [[Bandar Shapur]] with an 8,200-ton [[Lend-Lease]] cargo of [[fighter aircraft]], [[tank]]s, and [[explosive]]s destined for the [[Soviet Union]] — with one torpedo in her [[Port and starboard|port]] side at {{coord|01|00|N|071|15|E}}.<ref name=combinedfleetI37/> The torpedo detonated the explosives in her No.3 [[Hold (ship)|hold]], and the explosion showered burning debris over ''Henry Knox'', bringing her to a stop and setting her [[Deck (ship)|deck]] cargo and [[catwalk]] on fire.<ref name=combinedfleetI37/> At 19:07, her crew abandoned ship, with 25 crewmen and [[United States Navy Armed Guard]] personnel losing their lives in the explosion, the fire, and [[shark]] attacks, and after several explosions, ''Henry Knox'' sank by the bow at around 22:00.<ref name=combinedfleetI37/> Meanwhile, ''I-37'' surfaced, hove to, and ordered the [[chief mate]]'s lifeboat alongside.<ref name=combinedfleetI37/> Her [[navigator]] interrogated the survivors in the boat about their cargo, route, and destination, and about any [[Allies of World War II|Allied]] vessels they had encountered in the area, after which the Japanese ordered the men in the lifeboat to pass various items to ''I-37'' via a handline.<ref name=combinedfleetI37/> The Japanese confiscated the lifeboat's [[sail]]s, [[nautical chart]]s, some of its rations, and a [[flashlight]], but returned personal items, [[match]]es, and [[liquor]] to the lifeboat before departing the area.<ref name=combinedfleetI37/> The survivors then made for the Maldives in several groups. Before the last of them reached land on 30 June 1943, 13 of ''Henry Knox''′s 42 [[merchant mariner]]s and 13 of her 25 Navy Armed Guards personnel had died.<ref name=combinedfleetI37/> The survivors from the boat that had gone alongside ''I-37'' reported that she had a [[hangar]] and a [[degaussing]] coil, that her [[diesel engine]]s started without hesitation — indicating that the engines were in excellent condition and were using high-quality [[diesel fuel]] — and that a [[Stereopsis|stereoscopic]] camera equipped with a filtering mechanism was mounted on her [[conning tower]].<ref name=combinedfleetI37/>

By 1 July 1943, ''I-37'' was part of the Advance Force, as was the rest of Submarine Squadron 8 (the submarines {{ship|Japanese submarine|I-8||2}}, {{ship|Japanese submarine|I-10||2}}, {{ship|Japanese submarine|I-27||2}}, and {{ship|Japanese submarine|I-29||2}}).<ref name=combinedfleetI37/> On 9 July, she conducted a reconnaissance of the coast of the Persian Gulf. She returned to Penang on 17 August 1943.<ref name=combinedfleetI37/>

''I-37'' got underway from Penang in mid-September 1943 to begin her second war patrol, again in the Indian Ocean, with an embarked [[Yokosuka E14Y]]1 ([[World War II Allied names for Japanese aircraft|Allied reporting name]] "Glen") [[floatplane]], but soon thereafter one of her crewmen came down with [[appendicitis]], and she returned to Penang to seek medical attention for him.<ref name=combinedfleetI37/> She then set out again on 20 September 1943 to begin the patrol, assigned a patrol area in the [[Mozambique Channel]] and the vicinity of [[Mombasa]], [[Kenya Colony|British East Africa]].<ref name=combinedfleetI37/> On 28 September, the British [[Admiralty (United Kingdom)|Admiralty]] sent a message based on [[Ultra (cryptography)|Ultra]] information to Allied forces in the area warning them of the possibility that Japanese submarine-based [[seaplane]]s would conduct reconnaissance flights in the [[Gulf of Aden]], [[Gulf of Oman]], and an area west of [[54th meridian east|54 degrees East]] between [[1st parallel north|1]] degree 30 minutes North and [[1st parallel south|1]] degree South.<ref name=combinedfleetI37/> On 11 October 1943, ''I-37''′s floatplane reconnoitered the harbor at [[Antsiranana|Diego Suarez]], [[Madagascar]], its crew reporting the anchorage to be heavily guarded.<ref name=combinedfleetI37/>

Northwest of Madagascar, ''I-37'' torpedoed and sank the Greek 3,404-gross register ton [[merchant ship]] {{SS|Faneromeni}} on 23 October 1943.<ref name=combinedfleetI37/> She reported that she attacked two Allied merchantsmerchant ships in the Mozambique Channel southeast of [[Pemba Island]], one on 4 November 1943 which probably was the 2,850-gross register ton Norwegian [[Steamship|steamer]] {{SS|Hallbyørg}}, and a different ship during the afternoon of 5 November, and that each time she fired one torpedo, which missed the target.<ref name=combinedfleetI37/> Some historians since have suggested that ''I-37'' actually attacked ''Hallbyørg'' twice and fired three torpedoes on each occasion.<ref name=combinedfleetI37/> On 17 November 1943, ''I-37''′s floatplane flew a reconnaissance mission over [[Kilindini Harbour]] at Mombasa.<ref name=combinedfleetI37/>

Just after sunset on 27 November 1943, at 12:40 [[Zulu Time]], ''I-37'' torpedoed the Norwegian 9,972-gross register ton Norwegian armed tanker {{MV|Scotia|1939|6}}, which had separated from Convoy PB-64 to proceed independently during a voyage from [[Bahrain]] to [[Melbourne]], Australia, with a cargo of [[diesel oil]].<ref name=combinedfleetI37/> A torpedo hit ''Scotia''′s [[Port and starboard|starboard]] quarter, disabling her steering and bringing her to a stop, and she took on a 15-degree starboard [[Angle of list|list]].<ref name=combinedfleetI37/> Her crew abandoned ship while her first [[Engine officer|engineer]] and [[radio operator]] remained aboard to transmit an SSS signal,<ref name=combinedfleetI37/> a variant of the [[SOS]] signal indicating distress due to submarine attack. ''I-37'' fired another torpedo at ''Scotia'' which hit her in her starboard [[engine room]] at around 12:55 Zulu Time and broke her in two.<ref name=combinedfleetI37/> Her [[stern]] section immediately sank at {{coord|03|00|S|069|08|E|name=SS ''Scotia'' stern section}}, but the [[Bow (ship)|bow]] section remained afloat.<ref name=combinedfleetI37/> ''I-37'' surfaced and opened gunfire on it, sinking it as well.<ref name=combinedfleetI37/> {{nowrap|''I-37''}} took ''Scotia''′s master aboard as a [[prisoner-of-war]].<ref name=combinedfleetI37/> One survivor later testified that ''I-37''′s crew fired at his lifeboat with a [[submachine gun]], killing eight men.<ref name=combinedfleetI37/> On 29–30 November 1943, the patrol vessel {{HMS|Okapi}} rescued 31 survivors.<ref name=combinedfleetI37/> ''I-37'' returned to Penang on 5 December 1943.<ref name=combinedfleetI37/>

While ''I-37'' was on the surface in the [[Arabian Sea]] {{convert|200|nmi}} west of [[Diego Garcia]] at 20:30 on 26 February 1944, her lookouts sighted the British 5,189-gross register ton armed [[motor vessel]] {{MV|Sutlej}}, which, after departing [[Aden]] on 15 February as part of a convoy,<ref name=edwardsp107>Edwards, p 107.</ref> had detached from the convoy on 20 February midway across the [[Arabian Sea]] to proceed independently during a voyage from [[El Qoseir|Kosseir]], [[Egypt]], to Fremantle, Australia, with a cargo of 9,700 tons of [[Phosphorite|rock phosphates]] and [[mail]].<ref name=combinedfleetI37/><ref name=edwardsp107/> Soon after dark, the submerged ''I-37'' fired two torpedoes at ''Sutlej'' from a range of {{convert|2,190|yd|m|sigfig=3}}.<ref name=combinedfleetI37/> ''Sutlej''′s crew sighted an incoming torpedo and began an evasive turn,<ref>Edwards, p. 110.</ref> but one torpedo hit ''Sutlej'' in her port side, and she sank just under four minutes later at {{coord|08|S|070|E|name=MV ''Sutlej''}}.<ref name=combinedfleetI37/><ref name=edwardsp112>Edwards, p. 112.</ref> Her survivors abandoned ship in a lifeboat and several life rafts,<ref name=combinedfleetI37/> although many men ended up floating in life jackets in the water.<ref>Edwards, pp. 111–112.</ref> As men in the rafts and lifeboat were pulling other men from the water, ''I-37'' surfaced and used a [[searchlight]] to illuminate the area, discovering a teenage [[Indian people|Indian]] boy clinging to her [[rudder]].<ref name=combinedfleetI37/><ref name=edwardsp112/> After ''I-37'' took him aboard, her searchlight settled on one of the life rafts.<ref name=edwardsp112/> She brought the raft alongside, and her medical officer, speaking from the [[Bridge (nautical)|bridge]], interrogated the men aboard it about ''Sutlej''′s identity, cargo, departure port, and destination and attempted to identify ''Sutlej''′s master.<ref name=combinedfleetI37/><ref name=edwardsp113>Edwards, p. 113.</ref> Informed that he had gone down with his ship, ''I-37'' moved away, then attempted to ram the raft, succeeding only in pushing it aside with her [[bow wave]].<ref name=edwardsp113/> Nakagawa then ordered ''I-37''′s crew to open fire on the survivors.<ref name=edwardsp113/> ''I-37'' fired first at the raft, inflicting no casualties on its occupants, and then spent an hour moving systematically through the area, her crew machine-gunning every man floating in a life jacket they could find<ref name=edwardsp113/> while calling for ''Sutlej''′s master and [[chief engineer]] to give themselves up.<ref>Edwards p. 114.</ref> Sources disagree on ''Sutlej''′s death toll in the sinking and subsequent massacre, claiming that 43 men died immediately and two more while the remaining survivors drifted at sea,<ref>Edwards, p. 123.</ref> and that s total of 41 crew members and nine gunners from ''Sutlej'' perished before her suvivorssurvivors were rescued.<ref name=combinedfleetI37/> The [[Royal Navy]] [[whaler]] {{HMS|Solvra}} rescued ten crewmen and a gunner after they spent 42 days on a life raft,<ref name=combinedfleetI37/> and the Royal Navy [[sloop-of-war]] {{HMS|Flamingo|L18|6}} rescued 11 crewmen and a gunner after they had drifted at sea for 46 days.<ref name=combinedfleetI37/>

At 11:30 on 29 February 1944, the submerged ''I-37'' fired two torpedoes at the British 7,005-gross register ton armed [[Cargo ship|cargo]] steamer {{SS|Ascot}} — carrying a 9,000-ton general cargo of [[pig iron]], [[paraffin wax]], [[Gunny sack|gunnies]], [[linseed oil]], [[coconut]]s, and [[fiber]] and, according to different sources, making a voyage either from [[Calcutta]] in [[British India]] to [[Port Louis]], [[Mauritius]],<ref name=combinedfleetI37/> or from [[Colombo]], [[Ceylon]], to [[Antsiranana|Diego Suarez]], Madagascar, and then to Fremantle<ref>Edwards, p. 127.</ref> — in the Indian Ocean {{convert|800|nmi}} northwest of Diego Suarez. Madagascar.<ref name=combinedfleetI37/><ref>Edwards, pp. 129–130.</ref> One hit ''Ascot'' in the forward part of her engine room in her starboard side, killing four crewmen, knocking down both of her [[Antenna (radio)|trasmittertransmitter aerials]], destroying two of her lifeboats, and bringing her to a stop at {{coord|05|S|063|E}}.<ref name=combinedfleetI37/><ref>Edwards, p. 130.</ref> ''Ascot''′s 52 survivors abandoned ship in the two remaining lifeboats and a life raft.<ref name=combinedfleetI37/><ref name=edwardsp131>Edwards, p. 131.</ref> ''I-37'' surfaced {{convert|2,000|yd|m}} off ''Ascot''′s starboard quarter,<ref name=combinedfleetI37/> circled her once, and fired at ''Ascot'' with her deck gun for about 15 minutes, scoring no hits.<ref name=edwardsp131/> She then approached the lifeboats and raft, her medical officer calling in English for ''Ascot''′s master, [[Chief mate|chief officer]], and [[Radio operator|wireless operator]] to identify themselves.<ref name=combinedfleetI37/><ref name=edwardsp132>Edwards, p. 132.</ref> After the men aboard one of the boats responded falsely that all three of them were dead, following instructions given to all Allied merchant ship crews, ''I-37'' fired warning shots across the [[Bow (ship)|bow]] of the other boat, prompting her master, Captain Jack Travis, to identify himself.<ref name=combinedfleetI37/><ref name=edwardsp132/> ''I-37''′s crew brought him aboard the submarine and ordered him to identify his first officer, brought the first officer aboard as well to confirm Travis′sTravis's identifityidentity, and then retrunedreturned the chief officer to his lifeboat.<ref name=combinedfleetI37/><ref name=edwardsp132/> Nakagawa then screamed "English swine!" at Travis, slashed him across the palms of his hands with his sword, and shoved him overboard.<ref name=edwardsp133>Edwards, p. 133.</ref> Travis reached a lifeboat, but ''I-37'' rammed both lifeboats, spilling their occupants into he sea, and spent the next two hours methodically moving around the boats, machine-gunning men in the water and aboard the raft, killing many of them and sinking one lifeboat.<ref name=edwardsp133/> ''I-37'' then opened fire with her deck gun on the slowly sinking ''Ascot'', firing 30 rounds into her and setting her on fire;<ref>Edwards, pp. 133–134.</ref> she eventually sank.<ref name=combinedfleetI37/> ''I-37'' then resumed her attack on the survivors, ramming the raft and spending another two hours machine-gunnninggunning every ''Ascot'' survivor her crew could find before she took the remaining lifeboat under tow and finally departed the scene at 20:00, taking the lifeboat with her.<ref>Edwards, p. 134.</ref> ''Ascot''′s last seven survivors — four crewmen and three gunners — climbed back aboard the raft, from which the Dutch steamer or motor vessel (according to different sources) {{SS|Straat Soenda||2}} rescued them on 3 March 1944.<ref name=combinedfleetI37/><ref>Edwards, pp. 134–135, 136</ref>

Escorted by her floatplane, ''I-37'' departed Penang at 05:00 on 27 April 1944 bound for Singapore.<ref name=combinedfleetI37/> Around 08:00, when she was about {{convert|20|nmi}} south of Penang, an explosion occurred about {{convert|110|yd|m|sigfig=2}} off her port bow, apparently the premature detonation of a [[naval mine]] laid either by a [[Consolidated B-24 Liberator|B-24 Liberator]] [[heavy bomber]] of the [[7th Bombardment Group]] of the [[United States Army Air Force]]′s [[Tenth Air Force]] or by the Royal Navy submarine {{HMS|Taurus|P399|6}}.<ref name=combinedfleetI37/> The explosion rocked ''I-37'', knocking out her lights and [[Short circuit|short-circuiting]] an [[electric switchboard]].<ref name=combinedfleetI37/> ''I-37'' settled on the [[seabed]] in shallow water, then returned to Penang by the morning of 28 April.<ref name=combinedfleetI37/> An inspection at Penang revealed damage to the valves of two [[ballast tank]]s on ''I-37''′s port side.<ref name=combinedfleetI37/> She again departed Penang on 3 May 1944, this time arriving safely at Singapore on 5 May and undergoing repairs at Seletar.<ref name=combinedfleetI37/> On 10 May, ''I-37'' received a new commanding officer, Nakagawa moving to a new assignment.<ref name=combinedfleetI37/> In January 1947, he pleaded guilty before thean [[InternationalAmerican Militarymilitary Tribunalcourt forin the[[Yokohama FarWar East]]Crimes in [[TokyoTrials|Yokohama]] for the [[war crime]]s he committed while in command of ''I-37'' and was sentenced to eightseven years atin prison with [[hard labor]];.<ref>{{Cite heweb served|date=March six30, years1949 before|title=Headquarters heEighth wasArmy released on [[probation]]|url=https://www.online.uni-marburg.de/icwc/yokohama/Yokohama%20No.%20T339.pdf}}<ref name=combinedfleetI37/ref>

After completion of her repairs, ''I-37'' served as an [[antisubmarine warfare]] target in the anchorage at [[Lingga Island]] off Sumatra for ships of the [[2nd Fleet (Imperial Japanese Navy)|2nd Fleet]] between 09:00 and 13:30 [[Japan Standard Time]] on 21 July 1944.<ref name=combinedfleetI37/> On 9 September 1944, she arrived at Kure, Japan, for a refit and modifications involving the removal of her hangar, aircraft catapult, and [[deck gun]] and the installation of fittings for her to carry four ''[[kaiten]]'' manned [[Suicide attack|suicide]] torpedoes.<ref name=combinedfleetI37/>

On 7 November 1944, the commander of the 6th Fleet, [[Vice Admiral]] [[Shigeyoshi Miwa]], advised crews at the ''kaiten'' base at [[Otsu Island]] in [[Tokuyama Bay]] on the coast of Japan of the plan for Operation ''Kikusui'' ("Floating [[Chrysanthemum]]"), in which ''I-37'' and the submarines {{ship|Japanese submarine|I-36||2}} and {{ship|Japanese submarine|I-47||2}} were to launch ''kaiten'' attacks on the Allied naval anchorages at [[Ulithi Atoll]] and at [[Kossol Roads]] at [[Palau]].<ref name=combinedfleetI37/> Assigned to the Palau attack, ''I-37'' embarked four ''kaitens'' and their pilots for the operation, and all three submarines departed the Otsu Island base on 8 November 1944.<ref name=combinedfleetI37/> The plan called for {{nowrap|''I-37''}} to launch her ''kaitens'' off Kossol Roads on the evening of 19 November 1944.<ref name=combinedfleetI37/>

''Conklin'' gained contact on ''I-37'' at 16:03 and began her first Hedgehog attack at 16:15.<ref name=combinedfleetI37/> Twenty-five seconds after she fired her Hedgehog barrage, her crew heard a single underwater explosion.<ref name=combinedfleetI37/> Ten minutes later, ''Conklin'' fired a second Hedgehog pattern, and her crew heard another explosion 28 seconds later.<ref name=combinedfleetI37/> Although each explosion indicated a hit, ''I-37'' continued to maneuver, spoiling ''Conklin''′s third HegdehogHedgehog attack by turning inside it, resulting in no hits.<ref name=combinedfleetI37/>

At 16:45, ''McCoy Reynolds'' dropped a pattern of 12 [[depth charge]]s set to explode at a depth of {{convert|450|ft|0}}.<ref name=combinedfleetI37/> Her crew saw an air bubble about {{convert|25|ft}} in diameter rise to at least {{convert|5|ft}} above the surface, then heard a heavy underwater explosion.<ref name=combinedfleetI37/> ''McCoy Reynolds'' lost contact with ''I-37'' and had just regained it when at 17:00 a massive underwater explosion rocked her''McCoy Reynolds'', temporarily disabling her sound gear.<ref name=combinedfleetI37/> At 17:01, a huge air bubble reached the surface on her starboard bow at {{coord|08|07|N|134|16|E|name=''I-37''}}.<ref name=combinedfleetI37/> Several smaller explosions followed, and neither destroyer escort gained any further contact on ''I-37''.<ref name=combinedfleetI37/> Debris and oil reached the surface in sudden gushes over a large area around both ships.<ref name=combinedfleetI37/> By sunset, a [[whaleboat]] from ''McCoy Reynolds'' had retrieved wood stenciled with Japanese characters, polished pieces of instrument cases, deck planking, and a piece of human flesh with bits of [[steel]] embedded in it from the water, and by the time darkness fell an [[oil slick]] extended over several square miles as additional debris came to the surface, marking the demise of ''I-37''.<ref name=combinedfleetI37/><ref name=":1"/>

*{{cite book|last=Edwards |first=Bernard |title=Blood and Bushido: Japanese Atrocities at Sea 1941–1945 |year=1997 |publisher=Brick Tower P0ressPress |location=New York |isbn=1-883283-18-3}}

[[Category:ShipsWarships lost in combat with all hands]]