Pacific War, WW2 Japanese Submarines at Pearl Harbor
SUBMARINE FORCE

WEST COAST. Two submarines were sent to the West Coast.

I-10	04Jul44	DD-551,DE-185	Saipan
I-26	17Nov44	CVE-57,DE-415	E of Philippines .	Damaged Sara 31Aug42; sank Juneau 13Nov42
or	28Oct44	DD-??, DD-??	ENE Surigao

Note : This page describes only those submarines involved in the Pearl Harbor attack - about half of the Imperial Japanese Navy submarine fleet at the time of 64 boats. Another thirty or more boats started the war in the Western Pacific. An additional 126 I-class and RO submarines were completed during the war.
Submarines were renumbered later in 1942. These are the same subs : I-60 to I-85 were renumbered as I-160 to I-185.

"I" Boats - Long range fleet submarines. Almost half carry aircraft at the start.
    These were observed to carry a seaplane: I-7, I-9, I-10, I-19, I-21, I-25, I-26, and in SW Pac: I-29, I-30. These were designed to carry an aircraft, although a few traded the seaplane for a second deck gun : I-5 to I-11, I-13 to I-15, I-17, I-19, I-21, I-23, I-25 to I-45, I-54, I-56, I-58 . Most other subs were fitted to carry mini-subs.
I-201 to I-203 were snorkle equipped and came late in the war, 1945.
I-361 to I-373 were transport subs, 1944.
I-400 to I-402 were supersubs to carry three aircraft each to strike the Panama Canal, 1945.
I-501 to I-506 were Axis provided submarines.
RO- designation was for shorter range submarines ; about 50 subs.
Ha- indicated coastal boats including :
Midget-subs: 46 tons, 80 feet long, 6 feet diameter, 2 torpedoes, 16 hour range.
Two sizes of new mini-subs were building for the final defense of the home island at the end.

Chronology

"Most of the submarines departed from JAPAN for a rendezvous at KWAJALEIN, to proceed thence to HAWAII. A few, which were delayed in leaving JAPAN, changed course and proceeded directly to HAWAII.
The submarines continued operations in the vicinity of HAWAII from 8 December, the day of the attack, until early January of the following year. During this time, most of the submarines proceeded to the west coast of the UNITED STATES to destroy shipping, and part of the submarines returned to JAPAN. Only a small number remained in the Hawaiian area for the maximum length of time.

"The Japanese submarine detachment belonged to the Sixth Fleet, whose flagship was the light cruiser Katori. In early November orders for war preparation were given to this detachment, and on 11 November over ten submarines of the First and 3rd Detachments, including "I" Nos. 69, 74, 75 and others left Yokosuka Naval Base, with knowledge of the growing war fever in Washington and Tokyo.

"The submarine fleet followed a course due east in line ahead, stretching over 20 miles. They navigated at surface speeds of from 12 or 13 to 20 knots. But when they got near the Hawaiian waters they extended and followed their respective courses. The duties of the submarine fleet were known as

(a) to feel the movements of American fleets around Pearl Harbor;
(b) to dispatch "special submarines" from their decks and to observe their war results;
(c) to attack escaping American war vessels, if any;
(d) to rescue operators of "special submarines", down fliers, and others wherever possible.

In Hawaiian waters the submarines floated on the sea in the night, and in the daytime they submerged to periscope depth. The schedule of Pearl Harbor attack at 0300 on December 8th was transmitted to the submarine fleet two or three days beforehand. On 7th "I No. 74" sighted the carrier Lexington but no trouble ensued.

"The surprise attack on Pearl Harbor was carried on as had been scheduled. Before this, five large sized "I" type submarines belonging to the First Submarine Detachment had launched "special submarines" from their decks. That was the departure of the now well known Commander Iwasa and other members of "special attack parties".

"The submarines followed the upheaval in the harbor only through occasional land explosions coming through the deep water, and they confirmed the Harbor Battle at night when they emerged from the bottom of the sea. At 1631 (2101 Hawaiian time) Rear Commander Watanabe of "I No. 69" detected from the periscope a huge fiery column which marked the end of the USS Arizona.

"Lt. Commander Watanabe's radio intercepted dispatches in relation to this were by the enemy and his "I No. 69" was pursued by enemy destroyers which dropped depth charges madly. Under this circumstance "I No. 69" dived 60 to 70 meters beneath the surface, though her ordinary diving capacity had been set at 30 meters. The submarine sustained damage here and there and finally was caught by submarine wires. She struggled hard and just managed to get away from the wires. Altogether this old submarine remained submerged about 39 hours. All hopes of rescuing fellow-fighters who had been shot down had been abandoned."

The notes from direct narration by Captain Watanabe and Rear Admiral Nakaoka end here.
Capt Watanabe perished with his submarine in 1943 around the Gilbert Islands.
RAdm Nakaoka was killed while captain of the crack cruiser Atago.

07Dec41: Pearl Harbor Attacked
    00:42 to 03:33. Five mini-subs launched for Pearl Harbor.
    03:42. Mini-sub sighted by coastal minesweeper Condor (AMC-14)
    04:04. Ward investigates Condor sighting.
    06:30. Antares (AKS-14) sights suspicious object, possibly a small submarine. Patrol ship Ward (DD-139) notified.
    06:33. Navy patrol plane circles and drops two smoke pots.
    06:37. Ward sees conning tower between Antares (AKS-14) and her tow, apparently headed for Pearl Harbor.
    06:45. Ward fires on mini-sub with a hit, attempts to ram, depth charges and sinks it.
    07:30. Ward echo-ranging latched on to another one, dropping depth charges but did not come up with concrete results.
    08:02. Minisub from I-16 may have torpedoed West Virginia and Oklahoma.
    08:33. Report of Japanese submarine in harbor channel. (minisub from I-22)
    08:37. Monaghan (DD-354) orders "all engines ahead flank speed" to ram submarine.
    08:40. Submarine observed to fire one torpedo up North Channel toward Curtiss (AV-4).
    08:40. Conning tower hit by 5" shell from Curtiss (AV-4), 4" from Perry (DMS-16) or 3" from Medusa (AR-1).
    08:44. Monaghan feels a slight shock and releases two depth charges; submarine rolls over.
    08:55. Submarine reported sighted in North Channel.
    08:20. Helm (DD-388) opened fire on submarine off Tripod Reef. No hits observed.
    10:04. St. Louis (CL-49) exiting the channel when two torpedoes approached. Just before striking the ship, they hit a reef and explode. [Who fired, I-16 mini?]
    11:27 Cummings (DD-365) made depth charge attacks.
    11:33 Breese (DM-18) traced a submarine, dropped 5 depth charges.
    11:39 Cummings (DD-365) made depth charge attack on a second contact.
    12:04 Gamble (DM-15) established sound contact with submarine and dropped three depth charges.
    Chew (DD-106) reports 28 depth charges dropped on eight different sonic contacts south-west of entrance buoy. Evidence indicated that two submarines were sunk.
    Blue (DD-387) One submarine either sunk or severely damaged by depth charging 4 miles from Diamond Head Light.

    The fifth midget sub washed ashore and was recovered; its commander captured (reader story); and is on display at Nimitz Museum in Fredericksburg, TX.
    Sunken remains of three midget subs were salvaged; one was returned to Japan.
    The remains of one has never been found.

07Dec41. 08:00. Unarmed U.S. Army-chartered steam schooner Cynthia Olson is shelled and sunk by Japanese submarine I-26 about 1,000 miles northwest of Diamond Head, Honolulu. She is the first U.S. merchantman to be sunk by a Japanese submarine in World War II. There are no survivors from the 35 men aboard.
07Dec41. Late afternoon Pearl Harbor time. Japan declared war on US & UK. [They had only "broken off negotiations" in Washington earlier that day, just after the attack started.]
09Dec41. Japanese submarine I-10 shells and sinks unarmed Panamanian-flag motorship Donerail 200 miles southeast of Hawaii. There are only eight survivors of the 33-man crew; all seven passengers perish.
10Dec41. SBD from carrier Enterprise (CV-6) sinks Japanese submarine I-70 in Hawaiian Islands area,
11Dec41. Japanese submarine I-9 shells unarmed U.S. freighter Lahaina about 800 miles northeast of Honolulu. The ship sinks the next day. Four die in lifeboat before rescue on 20Dec41.
14Dec41. Norwegian motorship Hoegh Merchant is torpedoed and sunk by Japanese submarine I-4 about 20 miles ENE of Oahu. All hands (35-man crew, 5 passengers) survive.
15Dec41. Kahului, Maui, Hawaii, is shelled by Japanese submarine from Squadron 2. Possible candidates for having carried out the shelling are I-2, I-3, I-4, I-5, I-6, I-7.
15Dec41. Johnston Island is shelled by Japanese submarine I-22
17Dec41. Seaplane from Japanese submarine I-7 reconnoiters Pearl Harbor.
17Dec41. Unarmed U.S. freighter Manini is torpedoed and sunk by Japanese submarine I-175 180 miles south of Hawaii.
19Dec41. Unarmed U.S. freighter Prusa is torpedoed and sunk by Japanese submarine I-172 about 150 miles south of Hawaii.
20Dec41. Unarmed U.S. tankship Emidio is shelled, torpedoed and sunk by Japanese submarine I-17 about 25 miles west of Cape Mendocino, California.
20Dec41. Unarmed U.S. tanker Agwiworld is shelled by Japanese submarine I-23 off Santa Cruz, California.
21Dec41. Coast Guard cutter Shawnee rescues 31 survivors of U.S. tanker Emidio, sunk the previous day by I-17 off Cape Mendocino, California.
22Dec41. Japanese submarine I-19 shell unarmed U.S. tanker H.M. Storey southwest of Cape Mendocino, California, but fails to hit.
23Dec41. Palmyra Island is shelled by Japanese submarines I-71 and I-72.
23Dec41. Unarmed U.S. tanker Montebello is torpedoed and sunk by Japanese submarine I-21 four miles south of Piedras Blancas light, California. I-21 machine-guns the lifeboats, but miraculously inflicts no casualties.
23Dec41. I-21 later shells unarmed U.S. tanker Idaho near the same location.
23Dec41. Japanese submarine I-17 shells unarmed U.S. tanker Larry Doheny southwest of Cape Mendocino, California, but the American ship escapes.
24Dec41. Unarmed U.S. freighter Absaroka is shelled by Japanese submarine I-17 26 miles off San Pedro, California; although abandoned, she is later reboarded and towed to San Pedro.
24Dec41. Unarmed U.S. steamship Dorothy Philips is shelled by Japanese submarine I-23 off Monterey, California.
27Dec41. Destroyer Allen (DD-66) rescues first of two groups of survivors from U.S. freighter Manini sunk by Japanese submarine I-175 on 17 December off Hawaii.
27Dec41. Coast Guard cutter Tiger rescues 14 survivors of U.S. freighter Prusa, sunk by Japanese submarine I-172 on 19 December. A second group of 11 survivors reaches safety after a 2,700-mile voyage, rescued by a Fijian government vessel and taken to Boruin, Gilberts.
27Dec41. Unarmed U.S. tanker Connecticut is shelled by Japanese submarine I-25 about 10 miles west of the mouth of the Columbia River.
28Dec41. Destroyer Patterson (DD-392) rescues second of two groups of survivors from U.S. freighter Manini sunk by Japanese submarine I-175
30Dec41. Japanese submarine I-1 shells Hilo, Hawaii.

1942
08Jan42. Seaplane from Japanese submarine I-19 reconnoiters Pearl Harbor.
11Jan42. Carrier Saratoga (CV-3) is torpedoed by Japanese submarine I-6, 500 miles southwest of Oahu, Hawaii.
23Jan42. Oiler Neches (AO-5) is torpedoed and sunk by Japanese submarine I-72, off Hawaiian Islands. The loss of the oiler forces cancellation of the projected raid on Wake.
25Jan42. Japanese submarine I-73 shells Midway Island.
27Jan42. Submarine Gudgeon (SS-211) torpedoes and sinks Japanese submarine I-73 240 miles west of Midway.
01Feb42. At Kwajalein, planes from Enterprise (CV-6) damage submarine I-23.
07Feb42. Seaplane from Japanese submarine I-25 reconnoiters Sydney, Australia.
14Feb42. Japanese submarine I-23 is last reported south of Oahu, Hawaii. She is not heard from again.
23Feb42. Japanese submarine I-17 shells oil refinery at Ellwood, California.
24Feb42. Seaplane from Japanese submarine I-9 reconnoiters Pearl Harbor.
26Feb42. Seaplane from Japanese submarine I-25 reconnoiters Melbourne, Australia.
01Mar42. Seaplane from Japanese submarine I-25 reconnoiters Hobart, Tasmania.
04Mar42. Two Japanese reconnaissance flying boats, refueled by submarines I-15 and I-19 at French Frigate Shoals, Hawaii, bomb Oahu, Hawaii, but cause no damage.
08Mar42. Seaplane from Japanese submarine I-25 reconnoiters Wellington, New Zealand.
13Mar42. Seaplane from Japanese submarine I-25 reconnoiters Auckland, New Zealand.
19Mar42. Seaplane from Japanese submarine I-25 reconnoiters Suva, Fiji Islands.
06Apr42. Unarmed U.S. freighter Washingtonian, en route from Suez to Ceylon, is torpedoed and sunk by Japanese submarine I-5 near Maldive Islands. Crew reaches land in less than a day's rowing.
19Apr42. Submarine I-74 rescues crew of guardboat 1 sunk by Enterprise aircraft on Doolittle Raid.
02May42. Planes carrier from Yorktown (CV-5) bomb Japanese submarine I-21 in the Coral Sea. I-21 reports being attacked by planes, but fails to specify by land- or carrier-based. US approach to the Solomons thus remains undetected.
05May42. U.S. freighter John Adams is torpedoed and sunk by Japanese submarine I-21 85 miles from Nouméa, New Caledonia.
19May42. Seaplane from Japanese submarine I-21 reconnoiters Suva Bay, Fiji.
19May42. Japanese submarine I-168 picks up phony message that Midway is "out of water" that confirms AF as Midway, the target for invasion.
24May42. Seaplane from Japanese submarine I-21 reconnoiters Auckland, New Zealand.
25May42. Seaplane from Japanese submarine I-9 reconnoiters Kiska and Amchitka, Aleutians.
26May42. Seaplane from Japanese submarine I-9 reconnoiters Kiska.
27May42. Japanese submarine I-19 prepares to launch her seaplane off the northern side of Bogoslof Island, Aleutians, but sights a U.S. destroyer and submerges hurriedly, irreparably damaging the aircraft.
27May42. Seaplane from Japanese submarine I-25 reconnoiters Kodiak, Alaska.
29May42. Seaplane from Japanese submarine I-21 reconnoiters Sydney, Australia
30May42. Seaplane from Japanese submarine I-10 reconnoiters Diego Suarez, Indian Ocean.
31May42. Seaplane from Japanese submarine I-10 reconnoiters Diego Suarez, Indian Ocean.
31May42. Japanese midget submarines from submarines I-22, I-24, and I-27 penetrate the defenses of Sydney. The midget subs are lost in the attack.
01June42. Seaplane from Japanese submarine I-10 reconnoiters Diego Suarez.
06June42. U.S. freighter Melvin H. Baker is torpedoed by Japanese submarine I-10 off Mozambique.
06June42. Japanese submarine I-168 attacks Yorktown (CV-5 ) damaged in the Battle of Midway; Yorktown and Hammann (DD-421) alongside are sunk.. Yorktown sinks the next day.
07June42. U.S. freighter Coast Trader is torpedoed and sunk by Japanese submarine I-26 about 35 miles southwest of Cape Flattery, Washington
21June42. Japanese submarine I-25 shells Fort Stevens, Oregon.
30June42. U.S. freighter Express is torpedoed and sunk by Japanese submarine I-10 off Mozambique
14July42. Unarmed U.S. freighter Arcata is shelled and sunk by Japanese submarine I-7 off Bethel, Alaska. I-7machine guns the life rafts killing one sailor.
22July42. U.S. freighter William Dawes is torpedoed by Japanese submarine I-24 off the coast of Australia.
26Aug42. Planes from carrier Wasp (CV-7) damage Japanese submarine I-17, Solomons area.
30Aug42. Seaplane from Japanese submarine I-19 reconnoiters Santa Cruz Island, Solomons.
31Aug42. Carrier Saratoga (CV-3) is torpedoed by Japanese submarine I-26, 260 miles southeast of Guadalcanal.
09Sep42. Seaplane from Japanese submarine I-25 drops incendiary bombs on forest near Mount Emily, ten miles northeast of Brookings, Oregon, in an attempt to ignite forest fires. It is the first time a Japanese aircraft has bombed the continental United States during World War II.
15Sep42. Reinforcement convoy from Espiritu Santo to Guadalcanal is attacked by Japanese submarine I-19, which torpedoes carrier Wasp (CV-7). At the same time, in one spread of torpedoes, I-15 damages battleship North Carolina (BB-55) and destroyer O'Brien (DD-415).
25Sep42. Japanese submarine I-5 is damaged by gunfire off Guadalcanal.
29Sep42. Seaplane from Japanese submarine I-25 drops incendiary bombs on a forest in southern coastal Oregon--the second and last time a Japanese aircraft will bomb the continental United States during World War II in an attempt to ignite forest fires.
29Sep42. Cargo ship Alhena (AK-26) is damaged by Japanese submarine I-4 south of San Cristobal Island, Solomons.
04Oct42. U.S. tanker Camden is torpedoed by Japanese submarine I-25 25 miles off the coast of Oregon and is abandoned.
05Oct42. PBY sinks Japanese submarine I-22 near Indispensable Strait, Solomons.
06Oct42. U.S. tanker Larry Doheny is torpedoed and sunk by Japanese submarine I-25 off the coast of Oregon.
09Oct42. Seaplane from Japanese submarine I-7 reconnoiters Espiritu Santo, New Hebrides.
10Oct42. U.S. tanker Camden, torpedoed by Japanese submarine I-25 on 4 October 1942, catches fire and sinks off the mouth of the Columbia River.
11Oct42. Japanese submarine I-25, homeward bound from her deployment off the U.S. West Coast, torpedoes and sinks Russian submarine L-16, bound for San Francisco, off Seattle.
12Oct42. McCalla (DD-488) is unsuccessful in attempt to sink Japanese submarine I-2 off Guadalcanal.
13Oct42. Seaplane from Japanese submarine I-7 reconnoiters Espiritu Santo.
14Oct42. Japanese submarine I-7 shells Espiritu Santo.
19Oct42. Seaplane from Japanese submarine I-19 reconnoiters Nouméa, New Caledonia.
Destroyer O'Brien (DD-415), damaged by submarine I-19 torpedo on 15Sept42, breaks in two and sinks en route to United States for repairs off Tutuila, Samoa.
23Oct42. Japanese submarine I-7 shells Espiritu Santo.
29Oct42. PBY sinks Japanese submarine I-172 west of San Cristobal Island, Solomons.
30Oct42. Seaplane from Japanese submarine I-9 reconnoiters Nouméa, New Caledonia
02Nov42. Seaplane from Japanese submarine I-? reconnoiters Efate Island, New Hebrides.
07Nov42. Off Guadalcanal, miscellaneous auxiliary Majaba (AG-43) is torpedoed by Japanese midget submarine launched from submarine I-20 off Lunga Point. Destroyers Lansdowne (DD-486) and Lardner (DD-487) depth charge I-20, but the submarine escapes. Midget sub, her mission completed, is scuttled.
08Nov 42. U.S. freighter Edgar Allen Poe is torpedoed by Japanese submarine I-21 in a spirited fight off Nouméa, New Caledonia.
10Nov42. High speed minesweeper Southard (DMS-10) sinks Japanese submarine I-15 off San Cristobal Island, Solomons,
11Nov42. Seaplane from Japanese submarine I-7 reconnoiters Vanikoro, Solomons;
11Nov42. Seaplane from I-9 reconnoiters Espiritu Santo, New Hebrides.
11Nov42. Seaplane from I-21 reconnoiters Nouméa, New Caledonia.
12Nov42. I-22 PT-122 Solomons
13Nov42. In the aftermath of the Naval Battle of Guadalcanal: light cruiser Juneau (CL-52), damaged by gunfire, is torpedoed and sunk by Japanese submarine I-26 as Juneau retires. [ Five Sullivan brothers.]
20Nov42. Japanese submarine I-175 is damaged when she runs aground at Truk, Carolines.
25Nov42. Japanese submarine I-17 lands 11 tons of supplies at Kamimbo Bay, Guadalcanal. Submarine missions to supply the beleaguered Japanese garrison on Guadalcanal will continue through the end of November.
28Nov42. Cargo ship Alchiba (AK-23) is damaged by Japanese midget submarine Ha.10, from submarine I-16, 3,000 yards northeast of Lunga Point, Guadalcanal
07Dec42. Cargo ship Alchiba (AK-23) is damaged by Japanese by another midget submarine Ha.38, from submarine I-24, off Lunga Point, Guadalcanal
09Dec42. Motor torpedo boat PT-59 sinks Japanese submarine I-3, engaged in a resupply mission to Guadalcanal, three miles northeast of Kamimbo Bay, Solomons.
20Dec42. Japanese submarine I-4 is engaged in a resupply mission to Guadalcanal when sunk by submarine Seadragon (SS-194) between New Britain and New Ireland.

1943
18Jan43. U.S. tanker Mobilube is torpedoed by Japanese submarine I-21 off coast of New South Wales, Australia, and eventually sinks.
22Jan43. U.S. freighter Peter H. Burnett is torpedoed by Japanese submarine I-21 east of Newcastle, Australia. When I-21 withdraws, the freighter is reboarded and towed to Sydney for repairs.
23Jan43. Japanese submarine I-8 bombards Canton Island.
30Jan43. Japanese submarine I-10 torpedoes and sinks U.S. freighter Samuel Gompers 115 miles from New Caledonia.
10Feb43. Japanese submarine I-21 pursues U.S. freighter Starr King and torpedoes her. She sinks under tow.
11Feb43. Destroyer Fletcher (DD-445) and seaplane from light cruiser Helena (CL 50) sink Japanese submarine I-18 in Coral Sea.
01Mar43. Japanese submarine I-10 torpedoes U.S. tanker Gulfwave west of Fiji, ship make it to Suva, Fiji.
30Apr43. U.S. freighter Phoebe A. Hearst is torpedoed and sunk by Japanese submarine I-19 southeast of Suva, Fiji Islands.
02May43. U.S. freighter William Williams is torpedoed by Japanese submarine I-19 near Suva, Fiji Islands.
16May43. U.S. freighter William K. Vanderbilt is torpedoed by Japanese submarine I-19 off Suva, Fiji Islands. I-19 then fires upon one lifeboat and two rafts, and questions the ship's master before departing.
18May43. U.S. tanker H.M.Storey is torpedoed by Japanese submarine I-25. west of Fiji while en route from Nouméa, New Caledonia, to San Pedro, California. I-25 then hastens the sinking by shelling the burning ship.
23May43. U.S. tanker Stanvac Manila torpedoed and sunk by Japanese submarine I-17 100 miles south of Nouméa, New Caledonia. Motor torpedo boats PT-165 and PT-173 being transported are lost.
26May43. Japanese begin evacuation of troops from Kiska to Paramushiro via submarines. Between 26 May and 21 June 1943, 13 boats will be involved in the operation that will eventually extricate 820 men. Three boats will be sunk (see 10, 13, and 22June43) and three (I-2, I -155, and I-157) damaged
10June43. Submarine chaser PC-487 is damaged when she intentionally rams and sinks Japanese submarine I-24 40 miles NNE of Shemya Island, Aleutians.
13June43. Destroyer Frazier (DD-607) sinks Japanese submarine I-9 one and a half miles east Kiska, Aleutians.
22June43. Japanese submarine I-7 , damaged by destroyer Monaghan (DD-354) 10 miles south of Cape Hita, runs aground, irrepairably damaged, 12 miles SSW of Kiska, Aleutians.
27July43. Scamp (SS-227) sinks Japanese submarine I-168 in New Hebrides.
11Aug43.U.S. freighter Matthew Lyon is torpedoed by Japanese submarine I-11 near Espiritu Santo, but reaches her destination under her own power.
13Aug43. U.S. freighter M.H. De Young is torpedoed by Japanese submarine I-19 near Espiritu Santo, but, remains afloat due to barge pontoons stowed in each hold. The ship able to be towed to port.
19Aug43. Observation plane sinks Japanese submarine I-17 off eastern Australia,
24Aug43. Seaplane from Japanese submarine I-25 reconnoiters Espiritu Santo.
31Aug43. U.S. tanker W.S. Rheem is torpedoed by Japanese submarine I-20 near Espiritu Santo, but reaches port under her own power.
03Sep43. Destroyer Elliot (DD-398) sinks Japanese submarine I-25, 150 miles northeast of Espiritu Santo.
11Sep43. Seaplane from I-26 reconnoiters the Fiji Islands.
16Sep43. German U-511 commissioned as Japanese submarine RO-500
24Sep43. U.S. freighter Elias Howe is torpedoed and sunk by Japanese submarine I-10 75 miles southeast of Aden in the Indian Ocean.
01Oct43. I-20 DD-510 Solomons
11Nov43. U.S. freighter Cape San Juan, bound for Townsville, Australia, with 1,348 embarked troops is torpedoed by Japanese submarine I-21. The ship sinks 2 days later; 130 troops killed.
24Nov43. Escort carrier Liscome Bay (CVE-56) is sunk by Japanese submarine I-175, Gilberts. Depth charges damage I-175 so that she cannot "go deep."
25Nov43. Destroyer Radford (DD-446) sinks Japanese submarine I-19 north of Gilberts.
21Dec43 .I-8 returns from only sucessful round trip voyage between Japan and Germany.
28Dec43. U.S. freighter Robert F. Hoke is torpedoed in the Indian Ocean by Japanese submarine I-26. The ship is towed to Aden but is written off as a total loss.

1944
02Jan44. U.S. freighter Albert Gallatin is torpedoed and sunk by Japanese submarine I-26 off the Arabian coast.
01Feb44. Destroyers Guest (DD-472) and Hudson (DD-475) sink Japanese submarine I-171, 15 miles west of Buka Island, New Ireland.
04Feb44. Destroyer Charrette (DD-581) and destroyer escort Fair (DE-35) sink Japanese submarine reported as I-21, 100 miles north of Jaluit, Marshalls.
17Feb44. Japanese submarine I-169 sinks herself by leaving a vent open while submerging during air raid on Truk.
04Mar44. Japanese submarine I-10 is damaged by depth charges E of Marshall Is.
13Mar44. U.S. tanker H.D.Collier is torpedoed and shelled by Japanese submarine I-26 in the Indian Ocean.
26 Mar44, Dutch freightr Tjisalak sunk in the Indian Ocean, by I-8 with crew tortured then murdered.
29Mar44. U.S. freighter, Richard Hovey is torpedoed by Japanese submarine I-26 in the Indian Ocean. I-26 then surfaces and after shelling the ship, fires upon the lifeboats and rafts, killing one sailor. The Japanese submarine then rams and sinks one of the boats before taking four POWs and clearing the area.

7 Apr44. Destroyer Saufley (DD-465) sinks Japanese submarine I-2, 50 miles west-northwest of New Hanover, Bismarcks.
12Apr44. PB4Y-2 flying out of Eniwetok attacks and sinks Japanese submarine I-174 in the northern Carolines. See 29Apr44 and reader stories.
29Apr44. TBF from small carrier Monterey (CVL-26), with destroyers MacDonough (DD-351) and Stephen Potter (DD- 538), sink Japanese submarine I-174 north of Truk. See 12Apr44.
19May44. England (DE-635) sinks Japanese submarine I-16, on a resupply run to Buka, 140 m. NE Cape Alexander, Solomon Islands.
    Japanese radio traffic intercepted allows deductions as to submarine cordon established to intercept American carriers; consequently, England (DE-635) sinks Japanese submarine I-16 as the first of five Japanese submarines that England will sink in a week's time as she works her way down the Japanese line.
24Jun44. TBM from Bogue (CVE-9) sinks Japanese submarine I-52 in Atlantic, 800 m. SW of Azores.

2July44. U.S. freighter Jean Nicolet is torpedoed by I-8 in Maldives, Indian Ocean. Much of crew is murdered.
4July44. David W. Taylor (DD-551) and Riddle (DE-185) sink I-10, attempting an evacuation mission 100 m. ENE of Saipan.
14July44. William C. Miller (DE-259) sinks Japanese submarine RO-48 75 m. E of Saipan and teams with Gilmer (APD-11) to sink I-6 70 m. E of Tinian.
19Jul44. Destroyer escort Wyman (DE-38) sinks Japanese submarine I-5, 360 miles east of Guam.
26Sep44. Destroyer escort McCoy Reynolds (DE-440) sinks Japanese submarine I-175 northeast of Palaus.

17Nov44. Planes from escort carrier Anzio (CVE-57) and destroyer escort Lawrence C. Taylor (DE-415) sink Japanese submarine I-26 in Philippine Sea near Palau.

1945
31Mar45. Destroyers Morrison (DD-560) and Stockton (DD-646) sink Japanese submarine I-8, 65 miles SE of Okinawa.

30May45. Aircraft from escort carrier Anzio (CVE-57) sink Japanese submarine I-12 (Ito) or I-361 (USN) in Philippine Sea 400 mile SE of Okinawa.
16July45. Aircraft from escort carrier Anzio (CVE-57) teams with destroyer escort Lawrence C. Taylor (DE-415) to sink Japanese submarine I-13, 540 miles E of Yokohama, Japan.