Mopping-up the Japanese Midget-Submarines

Japanese type-A midget sub salvaged near Pearl Harbor

By definition, a midget submarine is less than 150 tons, has a crew of no more than eight, has no on-board living accommodation, and operates in conjunction with a mother ship to provide the living accommodations and other support. The Japanese Navy built at least 800 midgets in 7 classes, but only a fraction had any noticeable impact on the war. Their intended purpose initially was to be deployed in front of enemy fleets, but their actual use would be in harbor attacks and coastal defense.

Japanese type-D sub sitting at the Yokosuka Naval Base, Sept. 1945

The Japanese midget subs were not named but were numbered with “Ha” numbers (e.g., Ha-19). These numbers were not displayed on the exterior and operationally the midgets were referred to according to the numbers of their mother ships. Thus, when I-24 launched Ha-19, the midget was known as “I-24tou” (designated “M24” in some texts). The “Ha” numbers were not unique either; some Type D’s were numbered Ha-101 through Ha-109.

In mid-1944, with coastal defense requirements becoming urgent, the Japanese Navy developed the Koryu Tei Gata Type D. More than just another improved version of the Type A, this was a new design. They were the largest of Japan’s midgets, displacing about 60 tons, 86 feet (26 meters) in length, with a five-man crew, featuring a more powerful diesel engine, and had improved operating endurance. Koryu’s armament consisted of two muzzle-loaded 17.7-inch torpedoes. As with the earlier types, individual boats had alpha-numeric names in the “Ha” series beginning with Ha-101.

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Some 115 units had been completed when Japan capitulated in August 1945. At the end of the war, Allied Occupation forces found hundreds of midget submarines built and building in Japan, including large numbers of the “Koryu” type; nearly 500 more were under construction. Some of these submarines intended for training pilots for Kaiten type manned torpedoes, had an enlarged conning tower and two periscopes.

Kaiten design

Kaiten submarines were designed to be launched from the deck of a submarine or surface ship, or from coastal installations as a coastal defense weapon. The cruiser, IJN Kitakami, was equipped to launch Kaiten and took part in sea launch trials of Type 1s. In addition, several destroyers of the Matsu class were also adapted to launch the weapon.
In practice, only the Type 1 craft, using the submarine delivery method, were ever used in combat. Specially equipped submarines carried two to six Kaiten, depending on their class.

After the end of the conflict, several of Japan’s most innovative and advanced submarines were sent to Hawaii for inspection in “Operation Road’s End” (I-400I-401I-201, and I-203) before being scuttled by the U.S. Navy in 1946 when the Soviet Union demanded access to the IJN submarines.

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Don’t Forget :

May is Military Appreciation Month, for this coming week….

May 8, 2019 – VE (Victory in Europe) Day

(Celebrated May 7 in commonwealth countries)

A day which marks the anniversary of the Allies’ victory in Europe during World War II

on May 8, 1945. Learn more…

May 10, 2019 – Military Spouse Appreciation Day

A day set aside to acknowledge the contributions and sacrifices of the spouses of

the U.S. Armed Forces. Learn more…

​LINK – Practical insights in caring for a military home front family

May 12, 2018 – Mother’s Day

LINK – Organizations that support deployed military personnel on Mother’s Day

LINK – Coloring page for military children

May 13, 2019 – Children of Fallen Patriots Day

A day to honor the families our Fallen Heroes have left behind – especially their children. It’s a reminder to the community that we have an obligation to support the families of our Fallen Patriots. Learn more…

SHAKE A VETERAN’S HAND TODAY!

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Military Humor – 

 

 

 

 

 

 

 

 

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Farewell Salutes – 

Melville R. Anderson (100) – Chicopee, MA; US Navy, WWII, ETO/PTO

Peter Badie Jr. – New Orleans, LA; US Navy, WWII

Memories of them…

Harry Belafonte – NYC, NY; US Navy, WWII (Home front)  /  Singer, actor, political activist

Alejandro Chavez – Miami, AZ; US Navy, WWII, PTO, USS Aubrain, engine room

Leroy Fadem (102) – Bronx, NY; US Navy, WWII, Lt. SG, USS Stevens & LST-871

Lester Finney – England, AR; US Air Force, SMSgt. (Ret. 28 y.), firefighter load master

Fletcher “Buster” Harris – Atlers, OK; US Army, WWII, 325th Glider Infantry

Richard K. Rowe – Limestone, TN; US Army, Vietnam, Ranger, 82nd Airborne Division, Purple Heart

John Seagoe – Cottage Grove, OR; US Navy, WWII, pilot

Cooper D. Wolfgram – Alamo, CA; US Army, HQ/SISCO/82nd Airborne Division

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OH NO!!

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About GP

Everett Smith served with the Headquarters Company, 187th Regiment, 11th A/B Division during WWII. This site is in tribute to my father, "Smitty." GP is a member of the 11th Airborne Association. Member # 4511 and extremely proud of that fact!

Posted on May 8, 2023, in Post WWII, SMITTY, Uncategorized, WWII and tagged , , , , , , , , , , . Bookmark the permalink. 134 Comments.

  1. Amazed again by the information on the midget submarines. I’m not sure how five to eight men would fit inside one of them. Was surprised at how many midget submarines were produced in Japan. Did any men ever survive the trip and go home?

    Liked by 1 person

    • Bev, I know of a couple, but there hasn’t been much research data I’ve seen. I doubt the pilots would not have been very talkative if they survived.

      Like

  2. Very interesting information. I am amazed about this mass production. Best wishes, Michael

    Liked by 1 person

  3. Thank you for all these additional stories and information, GP. These are things we never learned in school.

    Liked by 1 person

    • I know, right? I have said it a multitude of times – The more I’ve learned about that generation, the more amazed and grateful I am. – and it still holds true.

      Liked by 1 person

  4. If you are interested in light subject welcome.on blog: chapitrelumiere.wordpress.com

    Liked by 1 person

  5. Your knowledge, and ability to share it here just astounds me! Thank you for your diligent work and for enlightening people like me. I hope all is well in your world…have a super wonderful week!

    Liked by 1 person

  6. Children of the fallen patriots day what a wonderful idea. I was reading a news article this week that said Britain treats it military families and especially lone men very poorly. My cousin has come out of the RAF now with a lot of good training and discipline that has enabled him to become a senior heating engineer and start a family he is one of the lucky ones.

    Liked by 1 person

  7. Hey, GP. I got a kick out of the engineering comic.
    I wanted to let you know that my serial research took me to something you might enjoy, considering your interest in history. I was looking for creatures with green eyes and “designing” a new villain for the story — supernatural of course. If you get the research bug, look up “Old Green Eyes” (or just Green Eyes) and the Battle of Chickamauga. This weekend you’ll meet “Leonidas Gathright”. Hugs.

    Liked by 1 person

  8. Incredibly impressive research once again. 😊

    Like

  9. My dad was stationed on the last diesel sub the US had back in the 60’s and he always talked about how cramped it was. I can’t even begin to fathom the courage and dedication it took to climb into one of those tiny little tin cans and go out in search of the enemy. You would think with that kind of tenacity, and many other examples, Japan should’ve won the war, but I guess when you’re on the wrong side, it doesn’t matter just how fearless and full of fight your soldiers are.

    Liked by 1 person

    • Usually the enemy was located and the midget then released, but even so, I agree. Unfortunately, many of the men were considered disposable.

      Liked by 1 person

      • Towards the end of the war I think all men were disposable to Japan. The manned torpedo and kamikaze pilots are evidence of that. In some of the books I’ve read over the years they’ve talked about how the midgets couldn’t handle rough seas and how many of them turned over and sank soon after launching. Yet men kept getting in them.

        Liked by 1 person

  10. It looks, Japanese had pretty advanced technology and well developed economy for that time.

    Liked by 1 person

  11. Considering how many there were it would seem they were not used to their full effect. I can imagine though, after reading your description of them, that they were not the most comfortable submarines used.

    Liked by 1 person

    • I agree. I think with as many as they had, they could have done a lot more damage, but I understand it was difficult to them out in the area they were to be used. They were often used on kamikaze missions too.

      Liked by 1 person

  12. Well, that took me back, Sir. When I was living in digs, around 1965, I met an American who lodged with us for a while. I can only remember his first name, Kurt. He was part of the squad that made sure things were safe before entry into the underground areas. I was fascinated by listening to him.
    Took me back to happier days. Cheers!

    Liked by 1 person

  13. You never cease to amaze me with all you know about the military and their toys. Thank you! ❤

    Liked by 1 person

    • Thank you, Rachel. Some I already knew, but a lot was learned as I researched items. Often, I’d look up one piece of data and discover something totally unexpected!!
      Great to see you here again, Rachel.

      Like

  14. It took a brave and dedicated soul to squeeze into one of those things.

    Liked by 1 person

    • I’ll say!!!! I think I’m pretty patriotic, but that mission would NOT be carried out by me! I do not think they had a choice in the matter though.

      Like

  15. Cool post, GP. I’m fascinated by the tiny subs. Although the prospect of the reality of them is pretty terrifying. o_O
    Have a good rest of the week. Hugs.

    Liked by 1 person

  16. Good to see Harry Belafonte in the Farewell Salutes. He dropped out of high school to enlist in the Navy, but since black service members were not allowed to serve on the front lines (hard to believe, looking back!) his job was to load military ships heading for the Pacific theater. Just before he arrived at the California where this was done, military ships loaded with ammunition exploded killing more than 300 — two-thirds of them Black sailors. “It was the worst homefront disaster of World War II,’ Belafonte said years later, “but almost no one knows about it.’

    Liked by 1 person

    • It is true about Belafonte, but not African-Americans in the Pacific. For example, the highest ranking Japanese officer captured during the war in the Pacific was taken on the island of Morotai, Dutch New Guinea. What makes that event remarkable is the fact that those who captured him were members of the 93rd Infantry Division, 25th Infantry Regiment. Of the division’s 14,000 members, well over 90 percent were African Americans.
      My father also knew some, and they felt the African-Americans back home were given the plush jobs. The Navy also had blacks assigned as gunners. I suppose it was more segregated in Europe.

      Like

      • Man, I got some bad information on that, then — I forget where I read it. I had my doubts when I wrote that ‘black service members were not allowed to serve on the front lines’ — thanks for setting the record straight, GP, sorry for the balls-up.

        Liked by 1 person

  17. This was very interesting, GP. They were so tiny!

    Liked by 1 person

  18. Tanks for the good information about the subs.I never know there were so much different sorts

    Liked by 1 person

  19. Thanks for sharing these ancient submarines during WW11. Anita

    Liked by 1 person

  20. Today’s drug runners use small subs to move their merchandise stealthily. I wonder if they tried to copy any of these Japanese midgets.

    Liked by 1 person

    • Everything had to start somewhere. The U.S. had larger subs way back during the Civil War – and I couldn’t tell you how that idea came about. But, now that I think of it, bithe the Japanese in WWII and the drug dealers of today both participated in sneaky operations.

      Liked by 1 person

  21. I’m sure you know that three entered Sydney harbour on the night of 31 May. Two were destroyed. The Australian War Memorial in Canberra displays one which is a composite of them.

    Liked by 1 person

  22. they are so small

    Liked by 1 person

  23. “before being scuttled by the U.S. Navy in 1946 when the Soviet Union demanded access to the IJN submarines.” Sounds like a good decision, G. On another note, I couldn’t help but think of the submarines that were built during the Civil War.

    Liked by 1 person

  24. How would this compare to the USS Growler docked next to the Intrepid in NYC.

    Liked by 1 person

    • The Growler looks small because it is by the Intrepid, but it is a submarine. A midget sub is under 150 tons.
      Thank you, Kevin.

      Like

  25. I hadn’t heard of the midget subs. Were they used at all after WWII?

    Liked by 1 person

  26. I knew of the midget subs, but had no idea that there were so many different classes, let alone the number of them. As to the scuttling, was there any real chance of Russia getting its hands on them, do you know?

    Liked by 1 person

  27. A terrific post, GP. Amazing information about the midget subs. Thanks

    Liked by 1 person

  28. Wow, so many of the midget subs were made! Great informative post, GP. I’d use mopping (with two p’s), though. You can do a quick edit, if you want to.

    Liked by 1 person

  29. Great details, GP. I had no idea they built so many different midget subs.
    Best wishes, Pete.

    Liked by 1 person

  30. This is amazing, I never knew that there were so many of these subs built, GP. I’m glad that they are gone!

    Liked by 1 person

  31. A Japanese mini sub was the first ‘victory’ in WWII. The first US shot was at the entrance of Pearl Harbor, shortly before the attack. The first shot was taken by the men of the USS Ward. They missed. Their second shot sank the sub. My uncle was on that victorious gun crew, mostly of which were Naval Reservists from St. Paul.

    Liked by 2 people

    • I know some didn’t believe them either. They just couldn’t imagine Pearl NOT being a safe harbor. But they were proved quite correct! Was your father still on the Ward as she sailed to the Solomons?

      Like

  32. Never heard of them – fascinating info.
    In the USSR, we celebrated May 9th as the Victory Day because, even those surrender was signed on May 8th, the time difference made it May 9th in Russia.

    Liked by 1 person

  33. A very interesting post on a subject about which I knew very little, so thanks a lot for that.
    And if people get claustrophobia in an ordinary submarine, then a midget submarine must be a very, very difficult space to tolerate!

    Liked by 1 person

  34. I knew about the midget subs, but little. This was interesting.

    I always take note of how you introduce the Farewell Salutes. Each time, I think is the best, but this one might actually be. Thank you for your respect for these warriors.

    Liked by 1 person

    • I appreciate you saying so, Jacqui, but honestly, I feel I owe them at least this much (but so much more). My father, uncle, son and cousin all served during one war or another and so did the troops they served with.

      Liked by 2 people

  35. The HA-19 midget submarine is in Fredericksburg, Texas, at the National Museum of the Pacific War (previously the Admiral Nimitz museum). I still haven’t visited, but it’s still on my list. I’ll confess that Fredericksburg has turned into such an over-crowded tourist mecca, I usually just pass through on my way to somewhere else. I need to plan a visit in the ‘low season’ — like late January.

    Liked by 1 person

  36. Learned a lot, GP. Loved the cartoons. Thanks for listing the Military Appreciation dates in May. Think I will borrow them with attribution.

    Liked by 1 person

  37. Not much fun for the crew

    Liked by 1 person

  38. Another interesting and informative post. Thanks, GP.

    Liked by 1 person

  39. I learned a little about the midgets because of Uncle Don’s Hancock at Ulithi in late 1944. https://joynealkidney.com/2019/10/04/donald-wilson-ulithi-lagoon/

    Like

  40. I recall seeing a midget sub in a museum in Norfolk many decades ago. But I can no longer recall where it was found.
    I always enjoy your posts because of the details they include.

    Liked by 2 people

  41. I knew they had midget submarines, but I didn’t know that had that many or even multiple classes – wow!

    Thanks for all the respect you show to veterans and military personnel.

    Liked by 2 people

  42. christinenovalarue

    💙💙

    Liked by 1 person

  43. I’ve heard of these but did not know the Japanese Navy had so many of them.

    Liked by 2 people

  44. Thank you, Ned.

    Like

  45. Thank you, Pat.

    Like

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