Germany's Last Mission to Japan: The Failed Voyage of U-234

by Joseph Mark Scalia

When U-234 slipped out of a Norwegian harbor on her maiden voyage in March 1945, the submarine carried a precious assortment of armaments and a select group of officials destined for Japan. En route came word that Germany had surrendered, and the boat's commander, Johann Heinrich Fehler, suddenly found himself in a rogue submarine. U-234 was not only loaded with the most technically advanced weaponry and electronic detection devices of the era, but also two Japanese naval officers still at war with the Allies who preferred death to surrender. This dramatic account of the fateful voyage offers an intriguing look at the individuals involved. Until now, the legacy of U-234 has centered on her ominous cargo, including 560 kilograms of uranium oxide, the presence of which has been the focus of countless theories and conjecture. With this book Joseph Mark Scalia argues that the submarine's value lies not in her inanimate cargo but in the individuals accompanying the material to Japan. Through exhaustive research into U.S. Navy interrogation records, European and Japanese archives, and interviews with former U-234 crewmembers and other principals, Scalia has produced a fascinating portrait of proud warriors coping with defeat. Among them was a high-ranking naval judge sent to Tokyo to purge the residual elements from an infamous spy ring, an anti-aircraft and air defense expert, a top naval construction engineer, a radar expert, a Messerschmitt designer who later became project manager for the F-105 Thunderchief, and a Luftwaffe general who directed the 1939 aerial blitz of Poland and was implicated in the 1944 plot to assassinate Hitler. Because this is the first book to be solely devoted to U-234, it also provides a thorough examination of the 1600-ton Type XB minelaying submarine, from launch to surrender on 15 May 1945 to an American destroyer. In addition, the work evaluates the technology carried aboard--an actual ME-262 fighter and masking measures for submarines were included--and places the mystery of the uranium oxide cargo in perspective.

Genres: World War II, History

250 pages, Hardcover

First published April 1, 2000

Reviews

[Jon Bradley · Rating 4 out of 5]

I purchased my copy of this book used in hardback at a local antique mall in November of 2023. The story covers a little-known episode that took place at the very tail end of WW2 in Europe, when the German submarine U-234 was dispatched on a mission to Japan. Aboard the U-boat were German technical experts traveling as passengers and a cargo of blueprints, drawings, weapons, and weapons systems. The book covers the story behind why this mission was attempted. I knew Japan and Germany were allies in WW2, but I had little information on how these allies, widely separated by geography and ideology, actually worked together (or didn't work together, as it turned out). As the war entered 1944, Japan was becoming increasingly desperate to obtain advanced German war-making technology in a bid to stave off the American advance across the Pacific. Per the book, in the areas of electronics, aircraft design, rocketry, and other areas, Germany was years ahead of Japan, and the Japanese military knew this. Japan made numerous requests to Germany for aircraft and weapons, but mutual distrust between Germany and Japan made any transfer of sensitive, secret German materials and knowledge difficult. But finally as the war in Europe was heading towards Germany's defeat, the logjam broke and Germany began sending materials to Japan via the its only remaining practical means of doing so: by submarine. When U-234 departed on its weeks-long voyage in March 1945, it was stuffed with 150+ tons of top-secret cargo, including 560 kilograms of uranium oxide. Germany surrendered in early May 1945 while the submarine was still enroute in the Atlantic, forcing the sub's commander to decide whether to surrender, and to which nation. The sub and its crew and cargo wound up in American hands. The author tells the story of the voyage in great detail, and then examines each of the submarine's passengers, giving the background on why they were selected to go to Japan and what they were expected to do once they arrived. I found it all extremely interesting. I would give this book five stars, but there were a number of niggling technical errors that did nothing to take away from the telling but as a world-class pedant I just have a hard time overlooking. When a submarine is diving, its ballast tanks are "flooded" (filled with seawater), not "blown". There are many other similar errors. The appendix on the uranium oxide in the cargo is a complete jumble of pseudo-scientific technobabble that gets wrong just about every aspect of how uranium is processed for use in nuclear weapons. But I'm still giving the book four out of five stars.

[Pc MacDonald · Rating 3 out of 5]

This is a good book if you want the details of what was extracted from the cargo and crew of U-234.

Scalia's appendix regarding the U235 cargo is fraught with errors.

Scalia is totally clueless when it comes to the production of fissionable material. You DO NOT need a reactor to produce U235. You need electromagnetic separation, gaseous diffusion, or in more modern times, centrifuges such as are in use in Iran.

You need a graphite or heavy water moderated reactor to make mostly Plutonium, which can then be separated chemically from the remaining U238.

The Hiroshima bomb, “Little Boy” was a gun type U235 bomb. The Nagasaki bomb was a plutonium implosion bomb, essentially the same as the one detonated in New Mexico a few weeks before Little Boy hit Hiroshima. The Little Boy design was a “gimme” and was a sure thing. Fat Man was extraordinarily more complex and required testing in New Mexico.

See Richard Rhodes, “The Making of the Atomic Bomb.”

[Nick · Rating 3 out of 5]

Dry but it's non fiction.

[Colby · Rating 3 out of 5]

This book isn't about exciting spy espionage. In fact, the U-234's secret journey to Japan had barely even begun when Germany capitulated and the captain made the decision to surrender to the Americans.

What the book excelled at, however, was examining the reason's behind U-234's mission, its physical and human cargo and detailing the German and Japanese desperation at the end of the war. It was fascinating reading about the distrust and opinions the two supposed allies held about one another.

I was very surprised to find that Japanese technology lagged behind Germany and the Allies as much as three years and that they did not have the capability to reproduce German equipment. The Germans were forced to provide not only the specifications but also the technicians necessary for Japan to manufacture new weapon system. You would never expect that looking at today's Japan.

[Henry Cesari · Rating 3 out of 5]

Compelling regurgitation of the known facts. A lot of statistics (tonnage of the Japanese and German fleets over the decades). Fills in some holes in HHKs story, but certainly doesn't read like a novel.