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Successful German Uranium Oxide shipments to Japan during WWII

Caisson Guage

19 Oct 2003
😄 :

I would like to get information on how many successful German shipments of
Uranium Oxide reached Japan via submarines during WWII.

Thanking you in advance,

caisson guage
Young Croud !

As an ex-Navy man (4 Years) your post caught my eye. I saw something on this line on the history chan. last week and it was the first I heard of it. Most of the people on this forum are under 30 and don't get into war history often. If you ask about inter-net sites with Japanese history buffs on it it may help. I check out every link on Japan I come accross but I haven't seen one with older Japanese war vets? I,m sure there has to be a site with what you're looking for ! I never cease to be ammazed at all the info. You might need a translation program to really get into Japanese war history like Bable-Fish. Best of luck from a fellow history lover from the Nam-Era.

If I remember correctly, only one shipment of Uranium oxide was ever shipped to Japan, in the WWII but in the middle of the voyage, the war ended for the Germans, and they headed for the nearest intern port.
Oh, I also remember reading that the two Japanese officials that were on board disappeared misteriously.

If I see any information of this story on the internet, I'll leave here the link.
To Frank and Ln:

I'm aware of the failed voyage of U-234 in the spring of 1945. The two Japanese Naval officers. They were LCDR Hideo Tomonaga, a leading
submarine designer, and LCDR Genzo Shoji, an aircraft expert. Rather
than be captured by the Allies, they both decided to commit suicide.
They informed the CO of the U-234 of their decision, retired to their bunks
and took Luminol, a very powerful barbiturate and took more than 36 hours
to die. They were buried at sea on 5/11/45.

The U-234 carried 550 kilograms (1.213#) of Uranium Oxide. What I want to know is, were there any "successful" shipments to Japan, via submarine.

The following books will give the reader a very comprehensive account of the
fate of U-234:
"GERMANY'S LAST MISSION TO JAPAN: The Failed Voyage, of U-234" by
Joseph Mark Scalia (Available at amazon.com) and "DYNAMITE FOR HIRE" by Sellwood. (Available from your local library from (ILL) International
Lending Library; a copy is located at a university in Montgomery, AL)

Thanks for the prompt response,

caisson guage
Hello from New Zealand Caisson. I am an amatuer historian and a bit of an authority on the subject.

General Touransouke Kawashima of the Imperial 8th Army Laboratory project in what is now North Korea signaled General Oshima at the embassy in Berlin on 7 July 1943 requesting shipments of Uranium oxide.

The signal was encyphered on the type 097 cypher machine, known to Americans by the code name "Purple." These Purple messages were decrypted in Hawaii and the archives are now publicly available through the US Government.

The Nazi government was skeptical of the reason for this request and it was not until early November 1943 that Kawashima admitted the Uranium was desired for a Japanese Atomic weapon. Germany had a huge supply from what was then called Joachimsthal in Western Chzechoslovakia (now called Jay-c-mov) The metal was refined to yellow cake Uranium oxide by Auer Gessellschaft at Oranienberg north of Berlin.

Enigma signals have disclosed that 800kg of Uranium oxide mixed in an amalgam with mercury were awaiting the Japanese submarine I-52 at Lorient in June 1944. I suggest looking up I-52 on Wikipedia.

There are references to other I-class submarines which returned at least from France, but didn't make it to Japan, that these submarines also carried Uranium oxide amalgams in their keels.

Other likely candidates were the former Italian transport submarines renamed UIT-22/23/24/25. From recollection only UIT-24 and UIT-25 survived the war and were scuttled at Suido Sound in Japan.

German transport U-boats U-219 and U195 probably carried Uranium oxide but I have no evidence. These two arrived at Djakarta in November 1944 with 12 V2 rockets broken down into components for reassembly in Japan. U-219 was the last U-boat to reach the East from Germany, leaving France 23rd August 1944.

U-180 also set out on the same voyage but sank in the Gironde estury off Bordeaux. The vessel is now a war grave, but it's wreck would help to prove if there was Uranium oxide in the cargo.

Type V11F torpedo transports U1059 and U-1061 also sailed for Djakarta and may have had some Uranium cargo. Many of the type IX-D2 U-boats such as U-862 were slipped at a dry dock in Singapore to have their keels unloaded so some of the ordinary fighting u-boats may have had some uranium cargo too. The UIT submarines operated a virtual shuttle between Japan and Singapore so may have carried Uranium cargo unloaded at Singapore.

To finish off the story a German Ju-390 transport plane flew to Tokyo via the polar route according to the memoirs of German arms Minister Albert Speer. Soviet sources record that the Ju-390 transported millitary attache General Miya Otari from Prague and arrived Tokyo about 28 February 1945. I have been unable to find any biographical data on such a person, but quite interestingly General Oshima vanished from Berlin and was in Japan by August 1945. There is no historical account how he managed to reach Japan before Germany fell ?

It was unlikely to have carried any Uranium but there was some sharing of various military secrets after Hitler's order BFHQ 219/44 was issued in September 1944. Japan proposed to build copies of the Ju-390 in Japan and the flight was connected with this agreement.

A BV222 flying boat also reached a Japanese base at Sakhalin Island and possibly carried engines for the Japanese aircraft.

Japan was desperately trying to build a nuclear bomber to reach USA in 1945.

U-234 was the final of these transport U-boats. After it's surrender 560kg of Uranium oxide and two Me-262 jets were unloaded from her. There was also a 72 tonne discrepancy between her German manifest at Kiel and her US manifest at Portsmouth NH.

One likelihood is that she was unloaded at Kristiansand after an underwater collision with another U-boat off Denmark. Possibly some of U-234's cargo was transferred to the Bv-222 which reached Sakhalin.
Hope all this stuff helps :?
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