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DEPARTMENT OF THE NAVY -- NAVAL HISTORICAL CENTER
805 KIDDER BREESE SE -- WASHINGTON NAVY YARD
WASHINGTON DC 20374-5060

Online Library of Selected Images:
-- JAPANESE NAVY SHIPS --

"Kairyu" type Midget Submarines--
Photographs taken on Shore & Drawings

The small "Kairyu" type midget submarines were intended for local defense against the prospective invasion that confronted Japan in 1945. The design, which featured diving planes mounted on the hull amidships, was tested in 1943-44, with production beginning in early 1945. A total of 760 boats were planned. Over 200 were delivered by August 1945, the great majority of these having been constructed at Yokosuka. Though originally designed to carry two 45cm (17.7") diameter torpedoes externally, a torpedo shortage caused most, if not all, of these submarines to be fitted with an internal warhead, for employment on suicide missions.

The "Kairyu" type midgets displaced somewhat over 19 tons. Length appears to have varied, with the largest being about 57 feet long. Hull diameter was 4 1/2 feet, creating a tight fit for the two-man crew. Propulsion was an 80 horsepower electric motor with an 85 HP gasoline engine for battery charging and surface running. Speed was 10 knots submerged and 7.5 knots on the surface. Some units, used for training, had a second periscope mounted at the rear of their streamlined conning tower.

This page features photographs and drawings of Japanese "Kairyu" type midget submarines, and provides links to other views.

For additional images of Japanese "Kairyu" type midget submarines, see:

  • Japanese "Kairyu" type Midget Submarines -- Views of Boats Afloat.

    If you want higher resolution reproductions than the digital images presented here, see: "How to Obtain Photographic Reproductions."

    Click on the small photograph to prompt a larger view of the same image.

    Photo #: NH 78667

    Japanese Midget Submarines:
    Type D ("Koryu") class
    -- at top and center -- and
    "Kairyu" class -- in lower left

    Sketch inboard profile plans, with hull section plans for the "Koryu" class.
    Copied from "Extracts from Small Battle Units of Foreign Powers, Appendix III: Japanese Midget Submarines and Explosive Motor Boats", page 38.

    U.S. Naval Historical Center Photograph.

    Online Image: 58KB; 740 x 500 pixels

     
    Photo #: 80-G-338384

    Japanese "Kairyu" Type Midget Submarines


    At the Yokosuka Naval Base, Japan, September 1945.
    Boat bearing numbers 4016 (at right) and 4018 (3rd from right) are training versions, with a second periscope mounted behind the main periscope's fairing.

    Official U.S. Navy Photograph, now in the collections of the National Archives.

    Online Image: 127KB; 740 x 615 pixels

    Reproductions of this image may also be available through the National Archives photographic reproduction system.

     
    Photo #: 80-G-338383

    Japanese "Kairyu" Type Midget Submarines


    At the Yokosuka Naval Base, Japan, September 1945.
    Several of these boats have numbers on their conning towers. Those with numbers 4016 (at left) and 4018 (3rd from left) are training versions, with a second periscope mounted behind the main periscope's fairing.

    Official U.S. Navy Photograph, now in the collections of the National Archives.

    Online Image: 111KB; 740 x 610 pixels

    Reproductions of this image may also be available through the National Archives photographic reproduction system.

     
    Photo #: 80-G-339847

    Japanese "Kairyu" Type Midget Submarine


    At the Yokosuka Naval Base, Japan, 7 September 1945, with grafitti added by members of the Allied occupation forces.

    Official U.S. Navy Photograph, now in the collections of the National Archives.

    Online Image: 78KB; 740 x 600 pixels

    Reproductions of this image may also be available through the National Archives photographic reproduction system.

     
    Photo #: 80-G-379158

    Japanese "Kairyu" Type Midget Submarine


    Outside its cave hideaway in a Japanese coastal hillside, 22 September 1945. The men alongside it are from USS Boston (CA-68), one of whose photographers took this photo.

    Official U.S. Navy Photograph, now in the collections of the National Archives.

    Online Image: 110KB; 740 x 615 pixels

    Reproductions of this image may also be available through the National Archives photographic reproduction system.

     
    Photo #: NH 78662

    Japanese "Kaiyu" Type Midget Submarine


    On the dock at a Japanese port, circa October-December 1945.
    Halftone photograph, copied from the U.S. Naval Technical Mission to Japan Report S-01-7: "Characteristics of Japanese Naval Vessels, Article 7: Submarines, Supplement II", January 1946, page 130, figure 145.

    U.S. Naval Historical Center Photograph.

    Online Image: 97KB; 740 x 535 pixels

     
    Photo #: NH 78664

    Japanese "Kaiyu" Type Midget Submarine


    Out of the water and resting on blocks at a Japanese port, circa October-December 1945. This submarine appears to be one of the two-periscope training units.
    Halftone photograph, copied from the U.S. Naval Technical Mission to Japan Report S-01-7: "Characteristics of Japanese Naval Vessels, Article 7: Submarines, Supplement II", January 1946, page 134, figure 153.

    U.S. Naval Historical Center Photograph.

    Online Image: 98KB; 740 x 595 pixels

     
    Photo #: NH 78663

    Japanese "Kaiyu" Type Midget Submarine, Number 2000


    View inside the tail section, looking aft, circa October-December 1945.
    Halftone photograph, copied from the U.S. Naval Technical Mission to Japan Report S-01-7: "Characteristics of Japanese Naval Vessels, Article 7: Submarines, Supplement II", January 1946, page 133, figure 151.

    U.S. Naval Historical Center Photograph.

    Online Image: 125KB; 740 x 595 pixels

     
    Photo #: 80-G-429385

    Japanese Kairyu type midget submarine


    On exhibit in cutaway form at the Yokosuka Naval Base, Japan, 11 May 1951. It is being examined by two U.S. Navy Sailors, including Fire Controlman 2nd Class Charles L. Carroll, who is on leave from USS Saint Paul (CA-73).
    A small experimental midget submarine is also on exhibit, in the right background.

    Official U.S. Navy Photograph, now in the collections of the National Archives.

    Online Image: 101KB; 740 x 620 pixels

    Reproductions of this image may also be available through the National Archives photographic reproduction system.

     

    For additional images of Japanese "Kairyu" type midget submarines, see:

  • Japanese "Kairyu" type Midget Submarines -- Views of Boats Afloat.


    If you want higher resolution reproductions than the digital images presented here, see: "How to Obtain Photographic Reproductions."


    Return to Naval Historical Center home page.

    19 April 2000