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How Close was Hitler to Launching an A-Bomb?

How Close was Hitler to Launching an A-Bomb?

How close was the leader of the Third Reich to having a nuclear bomb to deploy against the Allies in World War II? After developing a V2 ballistic missile capable of reaching as far a New York, Hitler made nuclear development his highest priority. Watch to discover the least-known close call in modern history.

Hitler may have been close to building an atomic bomb

According to German media, it’s cause was what first appeared to be a nondescript but shiny lump of metal.

Then the 64-year-old hobbyist, Bernd Thälmann, gave it a quick test.

This was odd. Thälmann had been scouring the terrain around Oranienburg in Brandenberg for some time. He had some experience in what to expect to find.

After bringing it home and leaving it laying around for several days, he and his children began to do some digging on the properties of various metals.

What they found caused them to became somewhat anxious. He notified authorities.

He suddenly became the center of a huge emergency services effort — including the evacuation and cordoning off of surrounding homes.

Nazi link

Men in hazmat suits moved into his house and carefully packed his find into a special lead-lined container, which was itself put in a protective suitcase.

Now Thälmann’s being investigated for possessing “unauthorized radioactive substances.”

Police have confirmed Thälmann’s metallic find is radioactive. And they’ve also reportedly suggested a source.

Oranienburg was, during World War II, the location of a secret research facility.

It was working on enriching uranium oxide sourced from South America.

Its objective was to create weapons-grade plutonium. This was to be the core a Nazi atomic bomb.

The research facility is long gone.

But it seems some rather telltale traces still remain.

Priority target

Britain and the United States were well aware of Hitler’s atomic bomb ambitions.

They strove hard to disrupt it.

The daring raids by British Mosquito fighter-bombers and British-Norwegian saboteurs to destroy a nuclear research plant in Norway has been the subject of several books and films.

But some 16,000 bombs were dropped on the Oranienburg facility during the war.

It was completely destroyed.

Despite the fact the Soviets carefully scoured the site after steamrollering through Germany in 1945, it’s highly likely more radioactive material remains among the scattered rubble.

But Thälmann doesn’t want to tell police where he found his piece.

He wants to go back there to find more evidence of the Nazi bomb-making project.

“The finder refuses to provide information on the exact location,” a police statement reads.

This has landed Thälmann in heavy water.

As his find was an “unauthorized radioactive substance”, an investigation has been initiated and the find seized as part of an ongoing criminal investigation.

Charges are yet to be pressed, however.

Close call

Documents released earlier this year by the US National Archives reveal how close Nazi scientists came to developing the war-winning atomic bomb.

The APO 696 file is a survey of Nazi research concluded Hitler came close to assembling a basic warhead in 1944.

It includes testimony that such a weapon may even have been tested.

The file reports of German test pilot Hans Zinsser believed he saw a ‘mushroom cloud’ near a nuclear research facility at Ludwgslust in 1944.

His logbook — submitted as evidence to Allied investigators — reads “In early October 1944 I flew away 12-15 km (7-9 miles) from a nuclear test station near Ludwigslust (South of Lübeck.)

“A cloud shaped like a mushroom with turbulent, billowing sections (at about four miles) stood, without any seeming connections over the spot where the explosion took place. Strong electrical disturbances and the impossibility to continue radio communication as by lighting turned up.”

A second pilot reportedly observed the same thing an hour later, and an Italian correspondent who saw the blast reported his observations to Mussolini.

From Hitler to Stalin: The secret story how German scientists helped built the Soviet A-bomb

In the late 1940s, Soviet scientists worked hard on their own atomic project, and the help of captured (or invited) German colleagues was of great help.

Soviet soldiers might have been quite surprised when in 1945 they approached Baron Manfred von Ardenne&rsquos home near Berlin. As described by an eyewitness, the &ldquohalf-mansion, half-castle&rdquo was decorated with a sign in Russian saying, &ldquoDobro pojalovat !&rdquo (&lsquoWelcome&rsquo). &ldquoArdenne well understood how the wind was now blowing,&rdquo the officers joked.

Indeed, Ardenne, a scientist who developed the first broadband amplifier, contributed to establishing a stable radio system in Hitler&rsquos Germany, and he also worked on the Nazi&rsquos nuclear project. Caught in the Soviet zone of occupation, he knew that he now had to work for Moscow. And so did many of his colleagues.

Brains as trophies

The first Soviet atomic bomb test.

In spring 1945 it was clear that World War II was coming to a close, and both the West and the USSR were already preparing for the coming Cold War, with each side planning to develop incredible new weapons. Both sides wanted to use scientists from Nazi Germany to further their own new technologies.

The U.S. forced Wernher von Braun and Werner Heisenberg, two key scientists in the German nuclear project, to collaborate. But Moscow also captured some prominent specialists. As Vladimir Gubarev, a journalist who wrote a book on the Soviet nuclear program, emphasized, &ldquoOne shouldn&rsquot underestimate the German contribution to the development of the Soviet nuclear industry it was significant.&rdquo

The Baron and the Communists

Baron Manfred von Ardenne in his younger years.

One of those German scientists, Manfred von Ardenne, had an outstanding life. Born into a noble family but then a high school dropout, the Baron went on to become an extremely successful inventor with around a total of 600 patents, including the first high-resolution scanning electron microscope. Ardenne, however, was doomed to work with three totalitarian leaders: Adolf Hitler, Joseph Stalin and Erich Honecker.

After the Soviets arrived in Berlin, Stalin&rsquos official in charge of the Soviet atomic program, Lavrenty Beria, made Ardenne an offer that he couldn&rsquot refuse: drop the electronics and work on the Soviet A-bomb.

From Berlin to Sukhumi

Ardenne asked to be allowed to concentrate on the development of the isotope separation process for obtaining nuclear explosives, such as uranium-235 (and not on the bomb itself). Beria agreed. Later the scientist called his role in the Soviet nuclear program, &ldquothe most important deed that fortune and post-war events led me to.&rdquo

Ardenne, working in his laboratory.

Not that Ardenne wasn&rsquot familiar with uranium. As Vadim Gorelik put it in an article for Neue Zeiten, &ldquoDuring World War II, prisoners built for Ardenne a cyclotron and a uranium centrifuge that would have created material for the Fuhrer&rsquos nuclear bomb.&rdquo But Germany lost the war, and now Ardenne, with his laboratory evacuated, worked in Sukhumi (now Abkhazia) on splitting isotopes and was in charge of more than 100 people.

Ardenne&rsquos work was successful, and he was decorated with the Stalin Prize in 1947, and then again in 1953 with a Stalin Prize first class. In 1955, he returned to East Germany. Talented and unsinkable, Ardenne lived for 42 more years, doing important research in physics and medicine.

Hero of Socialist Labor

Physicist Nikolas Riehl - perhaps not as sharp-dressed as Baron von Ardenne yet even more important for the Soviet nuclear program.

Ardenne wasn&rsquot the only prominent German scientist &lsquoinvited&rsquo to work on the Soviet nuclear program. There was also physicist Gustav Hertz who won the Nobel Prize physical chemist Max Volmer, who later headed East Germany&rsquos Academy of Science Max Steenbeck, who pioneered the development of supercritical centrifuges and many others (about 300 in total).

Nikolaus Riehl possibly had the most interesting fate of them all. This physicist was born in tsarist St. Petersburg in 1901, moved to Germany in the 1920s, and 20 years later was forced to return. His Soviet colleagues called him &ldquoNikolai Vasilyevich,&rdquo because of his Russian roots.

Vladimir Gubarev recalls: &ldquoBoth the American and the Soviet secret services pursued Riehl after the war&hellip we were lucky enough &ndash and he worked in the USSR.&rdquo In the Elektrostal factory (Moscow Region) Riehl, along with other scientists, managed to create metal uranium necessary for making a bomb. For that he was awarded the title of &ldquoHero of Socialist Labor&rdquo &ndash the only German scientist to achieve such an honor.

&ldquoNikolas Riehl loved to wear his medal and demonstrated it anytime he could,&rdquo Gubarev wrote. &ldquoAll the money he received he gave to the German POWs working in Elektrostal, and they remembered that even decades later, as their memoirs attest.&rdquo

In 1949 the USSR had its own nuclear bomb, and in the 1950s, after the work of the German scientists was completed, most left for East Germany. Some, such as Riehl, even managed to defect to West Germany, leaving behind the socialist chapter in their lives.

With the Cold War unfolding, rivaling nuclear projects were not the only case of the USSR and the U.S. challenging each other: read our text on how the global superpowers faced each other in the Korean peninsula.

If using any of Russia Beyond's content, partly or in full, always provide an active hyperlink to the original material.

So Close: How These Leaders Nearly Took Out Hitler

The assasination plot could have meant an early end to the war.

Key point: The plot was a good one, but the blast did not kill Hitler. As a result, he was able to regain control and crush the consiprators.

For Nazi Party Führer (Leader) and German Reich Chancellor Adolf Hitler, July 20th, 1944 dawned as a routine working day at his principal wartime military headquarters, the Wolfsschanze (Fort Wolf) in the East Prussian forest of Rastenburg, some three hundred air miles from Berlin, in what is today Poland. He was to have his daily military situation conference at 1 pm.

That summer the news delivered to him at those sessions was always bad, as both the Western Allied armies and those of the Soviet Union were pressing in relentlessly on the long-secure borders of the “Thousand Year” Nazi Third Reich created by Hitler in 1933, barely 11 years earlier.

Would Mussolini’s Train be on Time?

The Führer’s Axis Pact partner-in-arms—former Duce (Leader) of Fascist Italy Benito Mussolini—was expected for a meeting with Hitler. His pending visit—the last the two dictators would ever have—meant that the German officers’ briefing of the Führer would be convened at 12:30 instead of at 1:00, in order to complete business in case of an early arrival of the Duce’s train at the nearby Gorlitz railway platform.

Other than this, there was no reason to expect anything out of the ordinary—let alone that Hitler himself would be almost killed that day by a time-bomb explosion engineered by his own officers!

On the Run, but Still Lethal

The importance of the failed anti-Hitler bomb plot of July 20, 1944 can hardly be overestimated. As former Wehrmachtsoldier and Towson University history professor Armin Mruck wrote, “Most of the American G.I.s who died in World War II died after July 20, 1944. Most of the material destruction in Europe occurred after July 20, 1944. While the German armies in the East were retreating, they were still capable of rendering the Soviet Army effective resistance. As a matter of fact, German troops were still in control of much of Europe.”

Had the plot succeeded and Hitler been either killed or removed, or the Nazis overthrown without his death, history might have been very different. The war possibly would have ended with no enemy troops on German soil, the Russians contained in Eastern Europe alone and many thousands more Jews, political internees and Allied prisoners-of-war liberated from various Nazi camps strewn across the length and breadth of occupied Europe.

But this was not to be, and the failure of the anti-Hitler plot became one of modern history’s great tragedies.

Into the Woods

Fort Wolf—so-called because of the Führer’s predilection for the wolf—was located in a damp, murky, mosquito-ridden pine forest on the eastern edge of the German Reich. Hitler’s war was conducted there under the tall, forbidding trees in an aura of both secrecy and seclusion, a sort of hidden Nazi Camp David.

There were three concentric rings of security in the area, with entrances guarded by stationed SS troops armed with submachine guns. Besides quarters for top Nazi Party and Wehrmacht(military) officials in the barbed wire-enclosed compound, there was a kitchen, theater, air-raid shelter and tea house, all encased in concrete and above—not below—ground (because of the shallow, watery soil).

This was the situation and the locale at Rastenburg at 10:15 am on July 20 when an airplane carrying Lt. Col. Claus Schenck von Stauffenberg traveling from Berlin to report to the Führer landed at a military airfield called Rangsdorf nine miles from Fort Wolf.

Would Hitler’s Luck Finally Run Out?

The handsome von Stauffenberg was the driving force behind a large military and civilian conspiracy against Hitler, which had begun as early as 1938, and included several nearly successful attempts to either arrest or kill the Führer. The plots had always failed, however, either because of Hitler’s almost incredible good luck (such as changing his travel plans at the last moment, or the occasion, in 1943, when a bomb placed aboard his Kondor aircraft failed to detonate), or the reluctance of anyone to actually approach him with a pistol and simply shoot him. The latter course meant, naturally, death—either being shot on the spot by SS guards if one was lucky, or slow torture later if not.

Von Stauffenberg was a most unlikely candidate for the melodramatic role of political assassin. The scion of a landed gentry military family, the count, at 37, had lost his right forearm, his left eye and two fingers of his left hand, plus injuries to his left knee and ear in an enemy land-mine explosion in 1942 in North Africa as part of Field Marshal Erwin Rommel’s famed Afrika Korps.

A Tenuous Alliance of Assassins

Like other conspirators, however, von Stauffenberg had come to believe that only Hitler’s murder would set in motion their long-planned putsch against the Nazi regime that they all detested. He, like they, believed that Adolf Hitler was leading Germany to destruction, and they were determined to replace both him and his infamous regime with a more moderate government that could win a reasonable peace from the Western Allies, and so prevent the Red Army of Soviet dictator Josef Stalin from overrunning their country, and much of the rest of Europe as well.

The conspiracy to depose Hitler and his minions included several diverse strains within German society: soldiers, labor leaders, churchmen and intellectuals.

Among the soldiers there were Field Marshals Erwin von Witzleben and “Clever Hans” von Kluge Generals Ludwig Beck, Friedrich Olbricht, Hans Oster, Karl Heinrich von Stulpnagel, Friedrich Fromm, Erich Fellgiebel and Helmuth Stieff. All these men believed that Germany had already lost the war militarily.

The conspirators, joined together in a loose alliance against the Nazis that was in constant danger of being discovered by the SS and Gestapo (as, indeed, this writer believes it was), lacked a leader to pull all the threads to one end—the assassination of the Führer. In the handsome von Stauffenberg they had finally found that man, and so it was that he arrived that hot and sultry morning at Rastenburg to meet his destiny.

(It is this author’s opinion—after decades of research on this topic and its relevant personalities—that both SS Reichsfuhrer [National Leader] Heinrich Himmler and his rival, Reich Marshal and LuftwaffeCommander-in-Chief Hermann Goring knew well in advance that something was in the works. Himmler had at his command the entire security apparatus of the Third Reich, while Goring had his telephone wiretapping Research Office, established by him in 1933 and not given over to Himmler the following year with the Gestapo. I believe both men realized that the war was lost and wanted to be Hitler’s successor. They knew about the plot but stood aside, did nothing, and were prepared to let events take their course. Neither was at the conference at which the bomb exploded but arrived later in response to the news about the assassination attempt. Also not present at Fort Wolf at the time were Dr. Josef Goebbels and Albert Speer they had scheduled a meeting in Berlin.)

Today: Kill a Dictator, Lead a New Government

In order to destroy Hitler, von Stauffenberg had to fly to East Prussia, enter the conference room and—using a pair of ice tongs to break an acid capsule that would provide a 10-minute fuse—place the time bomb (wrapped in a shirt) in his briefcase as close to Hitler as possible.

Following the explosion (which he somehow must avoid), he would then find a way to leave Fort Wolf, fly back to Berlin, and there lead the revolt in person! In one day von Stauffenberg would thus overthrow one government and start another—or so the plan went until fate intervened.

A Change of Venue and of Fate

The Count learned of the conference schedule change upon his arrival in Rastenburg and, in addition (a crucial fact) that the meeting site itself had been moved from a huge concrete bunker—Hitler’s own—to the Lagebaracke, or Conference Hut. An explosion in the bunker would, due to the enclosed, encased area, kill everyone immediately, while the wooden, thinly walled Conference Hut, with its entrance and windows, would allow much of the explosion’s pressure to escape the building, thus giving the occupants a fair chance of survival. This is, in fact, what occurred.

At 12:30, Hitler stood with 23 generals, officers and aides poring over maps spread out on a heavy oak tabletop, listening to several reports. At 12:32, von Stauffenberg broke the acid capsule of the two-pound bomb and placed the briefcase at the base of the table support a few feet away from the Führer. At 12:35 he left the hut to make an imaginary phone call. At 12:42 pm, the bomb exploded.

Don’t Count Your Dead Führers Until the Smoke Clears

To the watching von Stauffenberg outside, it seemed as if a 150-mm howitzer shell had hit the hut directly. Utilizing the ensuing confusion, he bluffed his way past the startled guards, out of Rastenburg and was airborne for Berlin by 1:15 pm, convinced that he had, indeed, killed Adolf Hitler. But Hitler lived.

So Close: How German Generals Almost Killed Hitler and Saved Countless Lives

When the bomb exploded, Hitler had been laying almost prone across the table, following a detailed report on Russian troop movements being given by Gen. Adolf Heusinger. The fact that an officer had moved the briefcase to the other side of the oak table support (thereby putting the support between the bomb and Hitler), plus the open windows and flimsy walls and roof, had saved Hitler’s life.

The bomb had gone off with a deafening roar. The windows were blown out, the roof buckled and part of it collapsed. One officer was actually blown out of the building altogether, landed on his feet and ran for help! Smoke and debris mingled in the air with the cries of the wounded and dying.

Inside, Army Field Marshal Wilhelm Keitel began calling out, “Wo ist der Führer?” (Where is the Leader?) In his excellent 1964 book, Nemesis of Power: The German Army in Politics, 1918-45, British author Sir John W. Wheeler-Bennett gives a detailed account of what happened to Hitler:

“His hair was set on fire, his right arm was temporarily and partially paralyzed, his right leg was badly burned. Both eardrums were damaged and his hearing affected. His trouser legs were blown off at the belt, and a heavy object from the roof had fallen across his back and buttocks, tearing a great piece of cloth from his tunic and bruising him that, as he later announced, he had ‘A backside like a baboon.’

“Hitler’s first impression was that they had been bombed from the air, then that a bomb had been thrown from the outside through the window or that it had been planted under the floor. According to all accounts, he behaved with calmness. Having extricated himself from the debris of the table and put out the flames in his hair and clothing, he allowed himself to be led by Keitel from the shattered hut to his own quarters, his right arm hanging slack at his side, his hair singed and a livid scarlet burn upon the sallow pallor of his face.”

It should here be recalled that, as an infantryman in the German Army during WW I on the Western Front, Hitler had experienced a full four years of intensive shelling and other combat conditions, winning the Iron Cross lst and 2nd Class.

Burned Trousers and Jacket Revered as Holy Relics

Twenty-four people were present in the hut at the time of the explosion. One died on the spot, three others died later of their wounds, two were severely wounded and others slightly, such as Hitler himself and Col. Gen. (U.S. equivalent to a four-star general) Alfred Jodl, who appears in several photographs taken later that day with his head bandaged.

As Hitler emerged from the wrecked hut, one of Nazi Propaganda Minister Dr. Josef Goebbels’ aides who was present reportedly heard the Führer mutter, “Oh! My best trousers! I only put them on yesterday!” These trousers—as well as Hitler’s torn tunic jacket—were later considered by the Nazis to be holy relics, and the Führer had them sent to his mistress, Eva Braun, for safekeeping. At the war’s end, as Hitler’s mountain chalet, The Berghof, was overrun by U.S. Army troops, his partially destroyed uniform was discovered. Two years later, it was burned.

The Duce’s Train is on Time Hitler Doesn’t Miss a Beat

Later that same afternoon, right on schedule, the Duce’s train from Italy slid up to the Gorlitz railway platform, and Hitler—cleaned and changed, his hair trimmed to hide the burning and a cape thrown over his shoulders (despite the stifling heat) to conceal his condition—greeted Mussolini with the startling news. The Duce—who had been overthrown the previous July in a palace coup in Italy—was stunned, and noticed that the Führer shook hands with his left hand.

The two men walked to the compound’s tea house with Heinrich Himmler, Hermann Goring, Reichsleiter, Secretary to the Führer Martin Bormann, Nazi Foreign Minister Joachim von Ribbentrop and a coterie of other lesser aides.

A Less than Congenial Tea Party

At 5 that evening, joined by German Navy Grand Adm. Karl Donitz, the bizarre tea party began. As Mussolini and the embarrassed Italian Fascist entourage looked on in amazement, and while Hitler sat silent and morose, the Nazi leaders began berating one another for their individual failures of war leadership, and Goring even reportedly took a swing at von Ribbentrop with his swagger stick Reich Marshal’s baton.

By chance, someone mentioned the 1934 anti-Storm Troop “Blood Purge,” almost an exact decade before this day’s events, and Hitler jumped up in a furious rage. “I will show them no mercy! I will put their wives and children into concentration camps!” He ordered Himmler to fly to Berlin immediately and put down the now-unmasked military revolt there. “If anyone offers any resistance, shoot him, regardless of who it is! Be pitiless,” he shouted at the Reichsfuhrer, who was only too happy and willing to agree, enmeshed as he himself was—as I believe—in the knowledge of this event beforehand.

Following the conclusion of this spectral scene, Hitler and his entourage escorted the departing Duce and his party back to their train for the return trip to German-occupied northern Italy, the Fascist Salo Republic of which the Duce was the nominal head as Hitler’s puppet satellite ruler. The two men would never meet in person again the war’s end less than a year later would see the Duce murdered and the Führer dead by suicide.

Operation Valkyrie in Full Swing

Meanwhile—in Berlin, Paris and on the Western Front in France—the codeword of the conspiracy, Valkyrie, had been given and the long-planned attempt to overthrow the Nazi regime and end the war was well under way in spite of what was then happening at far-off Rastenburg.

In the Reich’s capital, Col. Gen. Ludwig Beck and the other dissident army conspirators at the War Ministry Building arrested Home Army General Fritz Fromm (who was wavering between loyalty to both Hitler and the plotters) and his aides. Von Stauffenberg arrived by air from East Prussia, asserted that the Führer was dead, and the order was given for the arrest of Dr. Joseph Goebbels.

In Paris, the German Military Governor, Gen. Karl von Stulpnagel, ordered the arrest of the local SS and Gestapo officials, which was actually accomplished both speedily and with surprise. Despite all these developments, however, the German Commander-in-Chief of the Western Armies, Field Marshal Hans von Kluge, refused to surrender his troops to the Western Allies without official confirmation of the Führer’s demise. The plotters in Berlin were saying that this was, indeed, the case, and his own staff officers were urging him to act even if it was not, but the telephone lines from Rastenburg—amazingly uncut—were stating categorically that Hitler lived.

Uncut Telephone Wires and What Might Have Been

And so it was that the conspirators’ plans to install Field Marshal Erwin Rommel as the new Reich President, Field Marshal Erwin von Witzleben as the new Wehrmacht (Armed Forces) Commander, and Dr. Karl Goerdeler as the next Reich Chancellor came to naught because of uninterrupted communications from Fort Wolf to the outside world. Some historians have felt that, had Rommel not been seriously wounded by Allied aircraft fire on the 17th—just three days before the bomb explosion—the plot would have succeeded anyway, but that remains open to conjecture.

What actually happened is known, however, and, as Goebbels later sneered contemptuously, “They didn’t even know enough to cut the telephone wires!” This fact, and the Führer’s survival, were the two key elements in the plot’s overall failure.

Sometime around 7 that evening in Berlin, an army battalion loyal to the plotters was ordered to the Propaganda Ministry to seize Dr. Goebbels, who was then in conference with Albert Speer, Hitler’s architect and Nazi Minister of Armaments and War Production. Major Otto Remer commanded the troops, and demanded to see Dr. Goebbels, who in turn insisted that Hitler lived and that Remer, not he, was a traitor if he obeyed the orders of the rebels to arrest him.

“Do You Recognize My Voice?”

Next, Goebbels asked if Remer wanted to talk with the Führer. Stunned, the major agreed, and Dr. Goebbels immediately called Rastenburg. Hitler asked Remer, “Do you recognize my voice?” The major did, and from that moment on the plotters were doomed. Hitler ordered Remer to obey only Goebbels and Himmler, who arrived in Berlin around 8 pm. Joined by SS General Ernst Kaltenbrunner and SS Colonel Otto Skorzeny, the Nazis now launched their own counterattack against the plotters.

Meanwhile, at the War Ministry on the Bendlerstrasse in Berlin, the news of both Hitler’s survival and von Kluge’s refusal to join the foundering revolt was known, and the conspirators wavered. Fromm and his officers were released and took over the building themselves.

General Beck committed suicide, and, in order to hide his own complicity, General Fromm had von Stauffenberg and other conspirators placed before a wall in the garden and shot by a firing squad that very evening. In Paris, the detained Nazi officials were also released, and the plot collapsed. By 11:30 pm, it was all over.

Hitler and the Bomb

By McGeorge Bundy: McGeorge Bundy, Professor of History At New York University, Was Special Assistant To the President For National Security Affairs From 1961 To 1966. His New Book, Danger and Survival: Choices About the Bomb In the First Fifty Years,From Which This Article Is Adapted, Will Be Published Next Month.

IN DECEMBER 1938, JUST 50 YEARS AGO NEXT MONTH, TWO German chemists discovered nuclear fission. It was the research of German scientists - working in a country whose dictator had already determined on war in Europe - that opened the way to the atomic bomb and it was the ensuing fear that Hitler might be the first to have a bomb that led to Franklin Roosevelt's decision in October 1941 - two months before Pearl Harbor, at a time when the materials from which a bomb might be made did not yet exist - to launch what would become the Manhattan Project.

Three years and 10 months later, an American B-29 dropped the first atomic bomb on Japan. Yet despite an enduring public impression that American scientists had been racing the Germans all the way, and despite the genuine fears of Allied leaders at the time, the Germans never came close to making a bomb. This failure was not accidental it was the consequence of deep-seated realities in German physics, German politics and the German military situation.

The physicists of Germany in 1938 were numerous and able. They were as much interested as their colleagues abroad in the scientfic revolution set off by the chemists Otto Hahn and Fritz Strassmann. But from first to last their interest remained primarily scientific. Certainly the Germans never produced the quantity and quality of analysis on the bomb as a specific objective that was produced in England and America in 1940 and 1941.

In 1945, the leading German physicists were rounded up and held in custody in England, where they learned of Hiroshima and shared their reactions with hidden British microphones. Some held that they had not made a bomb because they never wanted to try, while others thought they had simply failed to discover any promising way to go about the job.

What is certain is that Adolf Hitler never established the close connection to first-class scientific leadership that both Churchill and Roosevelt enjoyed. Indeed, by a peculiar irony, Hitler's decisive contribution to the age of atomic weapons was the fear he provoked in others of what he might do. Although that fear was crucial to Roosevelt's decision to make a bomb, the historical record shows that Hitler's Germany never even tried.

LET US GO BACK TO THE GREAT DIS-covery of Hahn and Strassmann. It was not a German national discovery, not at all a product of government concern. It was open science, published at once, and it was the climactic event in a 30-year attack on the nucleus of the atom that had engaged such giants as Enrico Fermi in Rome, Frederic Joliot and Irene Curie in Paris, James Chadwick in Cambridge, England, and Ernest Lawrence in Berkeley, Calif. What Hahn and Strassmann did was to demonstrate -against all the assumptions of the physics of the day -that the nucleus of the uranium atom could be split.

Enrico Fermi had already shown that nearly every element in the periodic table might undergo a nuclear transformation when bombarded by neutrons. Uranium, when so bombarded, produced what seemed to be entirely new substances, results that the physics of the day could not explain. Fermi concluded that he had probably discovered new radioactive elements still heavier than uranium, elements he dubbed ''transuranic.''

In 1938, Hahn and Strass-mann began work on this ''transuranic problem.'' 'ɾxperiments in chemical separation of these substances now gave a remarkable result,'' Hahn recalled 20 years later. ''When we used barium as the carrier, three radioactive isotopes . . . came down with the barium. . . . Now the precipitates had to be either barium or radium . . .''

But the difference was crucial, for barium is element 56, near the middle of the table of elements, and Hahn knew that if they had indeed produced barium from uranium (element 92), they had done something that physicists still considered impossible - they had truly split the atomic nucleus. But had they produced radium or barium? Hahn and Strassmann tried two more experiments, adding to the solution small amounts of radium that they knew was radium. This newly added radium separated from the barium, but in the very same circumstances the puzzling radioactive isotopes did not. The conclusion literally forced itself upon them: ''Our artificial 'radium' could not be separated from barium for the simple reason that it was barium!''

In their first report, Hahn and Strassmann acknowledged that their experiments were at variance with 'ɺll previous experience of nuclear physics.'' They knew they had a remarkable result, and they also knew they had set large new problems for their friends in nuclear physics. And so it was when they published their results (and for this work Hahn later received the Nobel Prize).

Within weeks, it was clear to all the world of science that their report marked the beginning of a wholly new adventure in nuclear physics, full of intellectual challenges of all sorts. As the news spread, it became clear that now, for the first time, man might find a way to set loose the massive energy inside the atom.

Very soon, in England in early 1940, there was a second decisive insight. Two refugees from Hitler, Otto Frisch and Rudolf Peierls, themselves proceeding from an insight of Niels Bohr of Copenhagen, made an elegant theoretical demonstration that an explosion of great power would result if pure metallic light uranium -U-235 - in small amounts were brought rapidly together to make a sphere ''of critical size.''

The Frisch-Peierls memorandum was written after Hitler's war had begun it was kept deeply secret for a year while it was assessed by British scientists. The Americans, meanwhile, had mounted only a modest governmental effort, stimulated by Einstein's famous letter to Roosevelt late in 1939 warning of the possible consequences of nuclear fission. In 1941, the British shared their assessment of the Frisch-Peierls memorandum with the Americans, and it became the immediate cause of Franklin Roosevelt's great decision that October.

THERE WAS NEVER a parallel moment of choice in Hitler's Germany. Competent physicists did call the attention of civil and military authorities to the possibilities opened by the discovery of fission, and these authorities, although often divided against themselves, did make efforts to develop a coordinated research program.

But in Germany, the physicists themselves often resisted these bureaucratic efforts. A compelling example, and one that contrasts notably with what eventually happened in the United States, was the failure of a War Office plan to bring all the scientists concerned to Berlin. Although war had begun and the authority of the War Office was nominally complete, the plan 'ɼollapsed against the obstinacy of almost all the scientists,'' as the historian David Irving put it.

While the scientists agreed to help the project, their motives were those of scientists, not war makers. After all, the scientific problems themselves were of first-class interest, and the military sponsorship of the research was helpful because it offered protection against the call-up of their young men.

Working under this military protection, the separated German scientists kept individual control over the directions of their work on uranium. In 1939, this was the situation in every country. But unlike their counterparts in the United States and in Britain, the German physicists were never brought into a coordinated war effort. Though Germany was a totalitarian state, its nuclear scientists remained far more detached from political authority than did their colleagues in Britain and the United States.

Some of the best of them simply continued with their work, choosing subjects with no regard for any possible wartime result. Thus Otto Hahn himself continued to examine and analyze the various fragments produced by fission. Given the modest size of his laboratory, his results were impressive, though much less extensive than those produced by Glenn Seaborg and others during the course of the American effort. But what Hahn was doing was completely unrelated to any concerted German effort to produce anything at all for wartime use. He wanted it that way. Indeed, his colleague Werner Heisenberg later remembered Hahn as ''loud in his warnings and counsels against any attempts to use atomic energy in war.''

Yet Hahn, like other uranium scientists, retained his protected position and his access to needed materials. His work was designated as '𧷬isive for the war effort'' - giving him preferred access to money, staff, and materials -although in reality it was nothing of the kind. And while in 1939 it could well have been argued that such pure science deserved support, at least on a modest scale (and Hahn's work, at its height, was receiving only $60,000 a year), by the latter part of the war it was plain to everyone who knew what was going on that the object of work like Hahn's was the preservation of German science, not the prosecution of Hitler's war.

At the laboratory level, the German scientists, independent and divided as they were, made much progress. They understood early both the importance of separated U-235 and the possibility of what others found and named plutonium - they thus identified the two major sources of a nuclear explosion. Yet they never thought either one was obtainable within the constraints of wartime urgency and difficulty.

They thought the production of power was a more likely practical result, and they focused their attention on achieving a chain reaction that might lead to a ''uranium engine.'' In this work, they made important mistakes that might have been corrected by a larger and more collegial effort thus they accepted a wrong experimental conclusion that graphite would not work in a reactor and so became wholly dependent on heavy water, which they could only get from a plant in Norway that later became the target of intensive Allied bombing.

THE MOST IMPOR-tant figure in the German effort was Werner Heisenberg, only 40 years old in 1941. He had been 25 when he enunciated the principle of uncertainty - an extraordinarily subtle statement of what can and cannot be known about physical phenomena. Heisenberg - his country's leading nuclear theorist a Nobel Prize winner a known defender of the then-denounced dean of ''Jewish physics,'' Albert Einstein, and a leading member of the German aristocracy of talent and intelligence - had unmatched standing among the German uranium scientists. To understand his course of action during 1941 and 1942 is to understand why German scientists never pressed their Government to make a nuclear weapon.

Heisenberg was brought into direct work on the uranium problem by military orders at the outbreak of the war in 1939. Like all atomic physicists, he had recognized the importance of the Hahn-Strassmann discovery, but he had told Enrico Fermi that year that he did not think there would be weapons in time to affect the coming war. In accepting the call to work on uranium, he was comforted from the start by this belief, and he saw himself as working to give his country a leading role in future peaceful uses of atomic energy. Until Hiroshima, he found no reason to doubt that the objective had been achieved he believed the German uranium scientists were still ahead.

As early as December 1939, Heisenberg had reported to the War Office that the fission process '⟊n on present evidence be used for large-scale energy production'' and that the surest way of 'ɻuilding a reactor capable of this will be to enrich the uranium 235 isotope'' - thus foreshadowing by 20 years the character of the first commercial reactors the Americans would build. Like Hahn, Heisenberg thought the separation of uranium 235 in usable quantities was beyond the wartime capacity of Germany, and he was content to leave that effort to others.

Toward the end of 1941, Heisenberg said later, he was confident that the road to nuclear power lay open, and equally confident that there was no prospect of making a bomb in wartime Germany. ''Hence we were happily able to give the authorities an absolutely honest account of the latest development, and yet feel certain that no serious attempt to construct atom bombs would be made in Germany . . .''

We should not overstate the self-restraint of Heisenberg's position, for it rested in part on failures of scientific understanding. Heisenberg himself exemplifies one source of such weakness -the separation of the theoretical physicists from their experimental colleagues. Even in his work on the chain reaction for nuclear power, Heisenberg made mistakes that can be traced to his habit of keeping his distance from the experimental side of physics.

In this, Heisenberg's style contrasts strongly with that of J. Robert Oppenheimer, the director of Los Alamos, who had been an experimentalist before he turned to theoretical physics. At Los Alamos, as the Harvard physicist Gerald Holton recently wrote, ''the interlacing of the theoretical and experimental aspects was complete under Oppenheimer's influence and natural for all who worked with him.'' It was not so in Germany.

IN 1941, HEISENBERG'S thoughts were dominated by a quite different concern: Was there not a danger that colleagues in America, with a quite understandable view of Hitler, were going at full speed for a bomb? Considering this hazard, Heisenberg decided in October 1941 to go to Copenhagen and talk with Niels Bohr, a former teacher of his and a physicist of sufficient eminence to influence colleagues working in the Allied states.

''We were convinced that (Continued on Page 59) the manufacture of atomic bombs was possible only with enormous technical resources,'' Heisenberg explained after the war, ''. . . This situation gave the physicists at that time decisive influence on further developments, since they could argue with the government that atomic bombs would probably not be available during the course of the war. On the other hand, there might be a possibility of carrying out this project if enormous efforts were made.''

When Heisenberg set off to see Bohr in October, his probable intent was to explore the possibility that the physicists of the world might agree to hold back from a wartime bomb. Specifically, might the British and Americans hold back if they could be sure the Germans were not in the race?

We need not suppose here that Heisenberg's purpose was purely humanitarian. After the war, he told friends that he had hoped for a German victory, after which ''the good Germans would take care of the Nazis.'' Obviously that hope could not be realized if others got the bomb and used it on Germany first. His widow has written that ''he was constantly tortured by this idea,'' and she believes that ''the vague hope'' of warding off such an attack ''was probably the strongest motivation for his trip.''

Whatever his exact purpose, by his own admission he failed to carry it out. The master and a former favorite student were now separated by Hitler's war, and in more ways than one. Bohr the Dane was wary of Heisenberg the German, who, he had been told, had defended the Nazi invasion of Poland, and who was in German-occupied Denmark to give a German-sponsored lecture that the Danish scientists did not attend. Heisenberg was equally constrained the exploratory discussion he sought could be read by any Nazi as an attempt to strike a secret bargain with the enemies of Germany. ''I tried to conduct this talk in such a way as to preclude putting my life into immmediate danger,'' Heisenberg recalled in a letter published in 1956. ''This talk probably started with my question as to whether or not it was right for physicists to devote themselves in wartime to the uranium problem - as there was the possibility that progress in this sphere could lead to grave consequences in the technique of war.

'ɻohr understood the meaning of this question immediately, as I realized from his slightly frightened reaction. He replied as far as I can remember with a counterquestion. ɽo you really think that uranium fission could be utilized for the construction of weapons?'

''I may have replied: 'I know that this is in principle possible, but it would require a terrific technical effort, which, one can only hope, cannot be realized in this war.' Bohr was shocked by my reply, obviously assuming that I had intended to convey to him that Germany had made great progress in the direction of manufacturing atomic weapons. Although I tried subsequently to correct this false impression I probably did not succeed in winning Bohr's complete trust, especially as I only dared to speak guardedly (which was definitely a mistake on my part). . .''

Heisenberg is right about his ''mistake,'' and he understates its consequences. As it was, the conversation failed entirely, and worse. Bohr heard no proposal for international scientific restraint, and instead he formed the quite erroneous impression that the Germans were trying hard to make a bomb. When he reported this impression to his British rescuers in 1943, it only added fuel to the fears of the English-speaking Allies - an ironic result, for until he learned firsthand of the Allied effort, Bohr himself remained doubtful of the practicability of a wartime bomb.

But the perverse result of Heisenberg's expedition to Copenhagen does not diminish the fact that he and the German colleagues he consulted appear to have been the only scientists of standing, in any country, to try to explore the possibility during the war that scientists of all countries might hold back from the bomb. Very likely even a much more explicit demarche would have failed. If Bohr could conclude, as he apparently did, that Heisenberg's vague exploration was no more than 'ɺ German attempt at demolishing the feared American supremacy in nuclear physics,'' would that not have been the reaction also of physicists in England and the United States, who were just then reaching their own conclusion that there must be an all-out Allied effort?

Yet Heisenberg at least tried to try, and perhaps a more searching question is: What might have happened if any such inquiry or exploration had come to him from the Allies? Might he have found effective ways to give them confidence in what was, after all, the truth: That the Germans had no plan to make a bomb. And, if so, could the Allied program, begun by Roosevelt only weeks before Heisenberg and Bohr had their talk in Copenhagen, really have been derailed?

APART FROM THE SCIEN-tific misjudgments, why were German physicists reluctant to push for a bomb? The answer lies in large part as with almost everything of consequence in Germany during the war - with the personality of one man: Adolf Hitler. For in the unwillingness of senior German physicists to press their master for support there was a certain prudence. If they should persuade Hitler to back them in going after a wonder weapon, they would have to produce results that matched his sense of urgency or face his wrath. It was better not to attract his attention.

The Fuhrer, in one part of his wild-and-crafty mind, was a believer in wonder weapons, but most of the time he trusted only what he had learned to trust as a corporal in World War I: tanks, U-boats, and, within limits, the aircraft that Goring pushed for. Albert Speer, Hitler's architect and from 1942 onward his minister of armaments, remembers him as 'ɿilled with a fundamental distrust of all innovations which, as in the case of jet aircraft or atom bombs, went beyond the technical experience of the First World War generation and presaged an era he could not know.''

In this respect, if no other, Hitler was of conventional mind. He was also profoundly wary of experts of all sorts and still more mistrustful of academic people. His view of nuclear physics, in particular, was hopelessly confused by his pathological anti-Semitism Jewish physics, he called it.

Hangers-on did push the atomic possibility at Hitler oddly, it was his postmaster general, Wilhelm Ohnesorge, who tried hardest, and who seems to have earned the almost predictable cheap sneer: Look who's trying to win the war!

Those who had to deal with the leader more seriously were more circumspect. The most important was Speer, who tells us with cool satisfaction that among all the 2,200 entries in the protocols of his official meetings with Hitler, the question of nuclear fission appears only once. Speer was not eager to stir up his master: ''I was familiar with Hitler's tendency to push fantastic projects by making senseless demands.''

Speer knew his man Hitler could indeed go from suspicious skepticism to absurd overexpectation. He did exactly that in the case of the V-2 rockets, which were used against London in 1944. But the uranium project was another matter. Both Speer and the scientists wanted to keep it away from Hitler's unpredictable attention, and they succeeded. The one ''very brief'' official protocol reports that at a conference in mid-1942, it was decided that while there is no wartime value in the uranium project, Speer plans to give its scientists the small amount of research money they are asking for. Speer wanted no reaction, and he arranged his report so as not to get one. He tells us that Hitler had talked about the matter sometimes, 'ɻut the idea quite obviously strained his intellectual capacity.'' Speer found Hitler content to be confirmed in his view that, as he wrote, ''there was not much profit in the matter.''

Speer's decisive recommendation followed a long meeting with Heisenberg and other physicists early in June. 'ɿollowing this meeting,'' recalled Heisenberg in 1947, ''which was decisive for the future of the project, Speer ruled that the work was to go forward as before on a comparatively small scale. Thus the only goal attainable was the development of a uranium pile producing energy as a prime mover - in fact, future work was directed entirely towards this one aim.''

Speer's recollection is somewhat different: ''. . . I asked Heisenberg how nuclear physics could be applied to the manufacture of atom bombs. His answer was by no means encouraging. He declared, to be sure, that the scientific solution had already been found and that theoretically nothing stood in the way of building such a bomb. But the technical prerequisites for production would take years to develop . . . .''

Speer asked the scientists to make a list of what they needed for further research and was ''rather put out'' by the modesty of their requests. He suggested that they take ''one or two million marks'' - they had asked for some hundreds of thousands - 'ɻut apparently more could not be utilized for the present, and in any case I had been given the impression that the atom bomb could no longer have any bearing on the course of the war.''

Thus the two principals, Speer and Heisenberg, struck a non-Faustian bargain. The physicists were given overriding priorities, but only for work at the research level. The postwar estimate was that expenditures on all aspects of the German uranium project were less than one-thousandth of the American effort.

From 1939 onward, the dominant motive of most German physicists had been to assure the protection of both their science and their scientists from Hitler's war. With Speer's knowing help they succeeded. There is a certain decency in what they did and did not do.

BUT DECENCY APART, even if Speer and the scientists had persuaded Hitler that nuclear weapons were the only road to victory, and even if he had given them a kind of sympathetic and patient support that was foreign to his nature, they could never have done the job in time. They were already well behind the Americans, who had taken the decision to proceed eight months before, and at the very best they would have been much slower to get the job done.

For the German scientists were weaker in every critical respect: in numbers and quality of scientists and engineers in the availability of large research instruments (they had no cyclotron to help them learn about plutonium) in breadth and depth of industrial resources in organizational flexibility, and, most obviously of all, in their vulnerability to air attack. After the war, with an eye to defending himself against possible German criticism of '⟺ilure,'' Heisenberg summarized the situation persuasively:

''We have often been asked, not only by Germans but also by Britons and Americans, why Germany made no attempt to produce atomic bombs. The simplest answer one can give . . . is this: because the project could not have succeeded under German war conditions. . . .

''. . .In 1942, German industry was already stretched to the limit, the German Army had suffered serious reverses in Russia in the winter of 1941-42, and enemy air superiority was beginning to make itself felt. The immediate production of armaments could be robbed neither of personnel nor of raw materials, nor could the enormous plants required have been effectively protected against air attack.''

Heisenberg continued: 'ɿinally . . . the undertaking could not even be initiated against the psychological background of the men responsible for German war policy. These men expected an early decision of the war, even in 1942, and any major project which did not promise quick returns was specifically forbidden. To obtain the necessary support, the experts would have been obliged to promise early results, knowing that these promises could not be kept. Faced with this situation, the experts did not attempt to advocate with the supreme command a great industrial effort for the projection of atomic bombs. . . .''

The German vulnerability to bombing is in itself decisive. Processing plants of the necessary size could never have been hidden, nor their purpose effectively disguised. After all, the Allies made the small heavy-water plant in Norway the target of repeated and largely successful attacks by both bombers and commandos. The vulnerability of large production plants would have been very great indeed compared to oil refineries or ball-bearing plants, nuclear installations are fragile things.

BECAUSE THEIR BEST physicists were not zealous for weapons, because they made uncorrected mistakes, because Hitler was Hitler, and because men like Speer always had more urgent production priorities, the Germans never really tried to make an atomic bomb, but if they had, they would have failed. Their country was in the wrong place at the wrong time.

So in the end it was the democrat Roosevelt who made the decisions that led to the first bomb and the extraordinary effort he called into existence two months before Pearl Harbor led to the weapons that were almost ready for use when he died in April 1945.

For Roosevelt, it was absolutely clear that if the thing could be done, it was vital that Hitler not do it first. Roosevelt's Government had no good evidence of what the Germans were and were not up to American understanding on the point was primitive in 1941 and remained so for three more years. But in such a case no news was bad news.

The Hitler that Roosevelt had in mind in 1941 was not the man that we have seen: reliant mainly on the weapons he already trusted, slow to support real novelty, scornful of Jewish physicists, and fearfully avoided by physicists themselves. He was rather the brilliant practitioner of military and political surprise, the victor on all fronts not yet clearly stopped on his road to Moscow, and the apparently unchallenged master of the resources, material and human, industrial and scientific, of most of Europe. Why would he not be well ahead in this matter, if he had chosen to be? Why would he not so choose? History has to be lived forward, and I cannot find it wrong that Roosevelt made his basic choice to go ahead. Still, looking back, it is well to remember that the Germans never entered the race for the bomb, that Adolf Hitler never understood the prospect, and that the best of the German physicists never really tried.

The Science Behind Hitler's Atomic Bomb And How We Stopped It

In the 1930s, as Europe stood on the precipice of World War II, a slew of nature's secrets were being revealed to scientists everywhere. The atomic nucleus was discovered to have multiple components -- protons and neutrons -- with different binding energies inside. Some atoms were naturally radioactive, either spitting out helium nuclei ( α decay) or electrons ( β decay) as they decayed into different, more stable elements, but others could have nuclear reactions induced in them by coaxing them into capturing neutrons. While the Sun took the lightest elements and fused them into heavier ones, releasing energy, the heaviest elements could be split apart, through the process of nuclear fission, into lighter ones, also releasing a tremendous amount of energy. When the first fissile element (Uranium-235) was discovered, it was immediately recognized that the reaction each Uranium atom undergoes gives off more than 100,000 times the energy of an equivalent mass of TNT exploding.

The way to get a fission reaction to occur was simple: bombard your fissile material with neutrons. Want to make the fission reaction more efficient? There are many things you can do:

In the United States, the Manhattan project scientists recognized all of this, and went down a number of avenues to ensure the success of their fission bombs.

Enriched samples of Uranium-235 and Plutonium-239 were produced: fissile materials that released tremendous amounts of energy when activated by neutrons, yet that also produced additional neutrons to continue a chain reaction. Both water and graphite were excellent mediums for slowing down neutrons, as the collisions between neutrons and those nuclei exchanged energy, slowing the neutrons down. Normal water (H2O), however, was no good, as the free protons in the hydrogen nuclei readily absorbed neutrons, creating deuterium. But if you used "heavy water," made out of deuterium (HDO) or even "double heavy water" (D2O) in lieu of water, the neutron absorption would be greatly reduced, enabling you to build a fission bomb of tremendous efficiency. In the 1940s, American scientists led by J. Robert Oppenheimer, Edward Teller and others figured all of this out, eventually succeeding in their endeavor. But at the same time in Nazi Germany, relative unknown Kurt Diebner and the theoretical titan Werner Heisenberg had figured out the exact same physics, and were working to build an atomic bomb of their own.

By the early 1940s, the Germans were well ahead of the allies in their efforts, having procured all of the ingredients necessary for the bomb save one: the heavy water, which was only available in Norway in one particular plant: Vemork. More than any other reason, this was the impetus for the 1940 Nazi invasion of Norway, forcing the Norsk Hydro scientists to accelerate production of this mysterious substance which -- it was joked -- was only good for improved ice rinks (since it froze at 4º C instead of normal water's 0º C) by 1942, more than a ton of it had been shipped to Germany. According to the calculations of Heisenberg and others, three-to-six metric tons were needed for a working fission bomb.

Yet the Nazis never completed their bomb, thanks to the combined efforts of the Norwegian resistance and the allied help of the British Special Operations Executive (SOE) to sabotage the heavy water production at Vemork. Led by Leif Tronstad, the Norwegian scientist who figured the Nazi plan out and escaped his occupied country to warn the allies, the journey involved everything from contaminating the heavy water with cod liver oil to trekking over 500 pounds of equipment through the frozen Norwegian winter, only to fall through the ice and fight with a dead battery. A brilliant attempt was made towards the end of 1942 to blow up the plant, but a glider crash resulted in the capture and execution of the saboteurs by the Gestapo in Nazi-occupied Norway. Yet in February of 1943, a second attempt, known as Operation Gunnerside, sent in an SOE-trained team of Norwegian commandos, and they succeeded in destroying the plant. Coincident with the Nazi defeat at Stalingrad, this truly marked a decisive turning point in the war. The destruction of the plant at Vemork became known as the most successful act of sabotage in all of World War II.

Yet the story didn't end there in 1944, the Nazis attempted to use the steam powered railway ferry, SF Hydro (or DF Hydro), to send the remaining heavy water to Germany in a last-ditch attempt to obtain the heavy water needed for an atomic bomb. The sinking of that ferry -- to the bottom of a 400 meter (1,400 feet) lake -- was perhaps the most critical victory in preventing Nazi Germany from obtaining the materials they needed for the atomic bomb. If not for the Norwegian resistance, Leif Tronstad and the British SOE, the entire rest of World War II (not to mention the future of the world since) may have unfolded very differently. As it stands, the fight over the world's largest production plant of heavy water is one of the most important, and yet one of the most under-told, stories in all of World War II.

I'm pleased to report that the full story of the plan to sabotage Hitler's atomic bomb is now told with both historical and scientific accuracy in Neal Bascomb's new book: The Winter Fortress. As someone who's thoroughly enjoyed a number of books about World War II history, this book has rocketed into my pantheon of the top suspense-filled stories about that era, along with Harrison Salisbury's The 900 Days, about the story of survival during the siege of Leningrad, and The Colditz Story, about the most successful P.O.W. prison break where over 300 men escaped from the highest security Nazi prison of all.

There's perhaps no better legacy to the history of this planet that Heisenberg is remembered for his uncertainty principle -- about the inherently indeterminate relationship between variables like position and momentum or energy and time -- rather than for his design of the weapon that allowed the Nazis to conquer the world. Instead, just four months after the sinking of the SF Hydro, the D-Day invasion took place. 11 months later, Germany surrendered. It's a rare case when the link between science, war and history are so clear, and yet it's quite arguable that we're only here today, living in relative peace and freedom on Earth, because of the brave actions taken in the 1940s by a group of saboteurs who saved the world.


The V-2 rocket was one of several innovative long-range weapons developed by the Germans after the failure of the Luftwaffe to strike a decisive blow against Britain. It was a revolutionary weapon—the world's first operational SRBM—that had been developed in a secret programme begun in 1936. The German leadership hoped that a barrage of rockets unleashed against London would force Britain out of the war. [5] Although Adolf Hitler was at first ambivalent, he eventually became an enthusiastic supporter of the V-2 programme as Allied air forces carried out increasingly devastating attacks on German cities. [6]

The 12.5-ton missile, standing 14 metres (46 ft) high on its launch pad, was fuelled primarily by liquid oxygen (LOX) and ethanol. Deploying the V-2 on a large scale required far more LOX than was available from existing production sites in Germany and the occupied countries. New sources of LOX were required, situated close to the missile launching sites to reduce as far as possible the loss of propellant through evaporation. The missile's operational range of 320 kilometres (200 mi) meant that the launch sites had to be fairly close to the English Channel or southern North Sea coasts, in northern France, Belgium or the western Netherlands. [7]

Because of the complexity of the missile and the need for extensive testing prior to launch, the V-2's designers at the Peenemünde Army Research Center favoured using heavily defended fixed sites where the missiles could be stored, armed, and fuelled from an on-site LOX production plant before launching. But the German Army and the V-2 project's head, Major-General Walter Dornberger, were concerned that the sites would be vulnerable to aerial attack by the Allies. The Army's preferred option was to use Meillerwagens, mobile firing batteries, which presented a much smaller target for the Allied air forces. [7]

The Army was nonetheless overruled by Hitler, who had a long-standing preference for huge, grandiose constructions. He preferred fixed installations along the lines of the virtually impregnable U-boat pens that had been built to protect Germany's U-boat fleet. In March 1943, [8] he ordered the construction of a massive bunker (now known as the Blockhaus d'Éperlecques) in the Forest of Éperlecques near Watten, north of Saint-Omer. The bunker was soon spotted by Allied reconnaissance, and on 27 August 1943, a raid by 187 Boeing B-17 Flying Fortress bombers wrecked the construction site before it could be completed. A surviving portion was reused by the Germans as a LOX production facility. [7]

The successful attack against the Watten bunker forced the German Army to find an alternative location for a launch site nearby. They had already taken possession of an old quarry between the villages of Helfaut and Wizernes, south-west of Saint-Omer and some 12 kilometres (7.5 mi) south of the Watten bunker, near the Aa river alongside the Boulogne–Saint-Omer railway line, about 1 km (0.62 mi) from Wizernes station. The quarry had been designated for use as a missile storage depot where V-2s would be housed in tunnels bored into the chalk hillside before being transported for launching. [9] The Germans undertook major work in August 1943 to lay extensive railway sidings to connect the quarry to the main line. [10]

On 30 September 1943, Hitler met with Albert Speer, the Minister of Armaments and War Production, and Franz Xaver Dorsch, the chief engineer of the Todt Organisation, to discuss plans for a replacement for the out-of-commission Watten facility. Dorsch proposed to transform the Wizernes depot into a vast bomb-proof underground complex that would require a million tons of concrete to build. It would be constructed within a network of tunnels to be dug inside the hillside at the edge of the quarry. A concrete dome, 5 m (16 ft) thick, 71 metres (233 ft) in diameter and weighing 55,000 tons, would be built over the top of the central part of the facility to protect it from Allied bombing. Beneath it, about 7 kilometres (4.3 mi) of tunnels were to be dug into the chalk hillside to accommodate workshops, storerooms, fuel supplies, a LOX manufacturing plant, generators, barracks and a hospital. [9]

Photo map of the area around the site before the bombing campaign

Plan of the Wizernes complex as built by September 1944 [11]

1944 conjectural reconstruction of the rocket preparation chamber and tunnels (on the assumption that A4 rockets were to be handled) [11]

A standard gauge railway tunnel, codenamed Ida, was to be built on a curving path that would connect it with both the east- and west-bound main line railway, allowing trains to run straight through the complex without needing to reverse or be turned around. This would serve as the main unloading station, where missiles and supplies would be offloaded onto trolleys that would transport them into the connecting galleries Mathilde and Hugo. Hugo connected in turn with Sophie, a dead-end railway tunnel branching from the main line into Ida. Each of the main tunnels had a number of unnamed side tunnels of the same dimensions as the main tunnels and up to 90 metres (300 ft) long. The central feature of the complex was a huge octagonal rocket-preparation chamber directly under the dome. It was never completed but would have been 41 metres (135 ft) in diameter and up to 33 metres (108 ft) high. A number of intermediate floors, possibly as many as ten, would have been built up the sides of the chamber. [12]

The western side of the chamber opened onto two tall passageways, opening onto two tracks to the outdoor launchpads, with the tracked passages and launchpads named Gustav (the southerly-located pad) and Gretchen (the northerly-located pad), both on the western side of the domed complex. Each was to have been protected by bomb-proof doors made of steel and concrete. The passageways were to be 4 metres (13 ft) wide and at least 17 metres (56 ft) high and were angled in a Y-shape, both exiting westwards into the quarry. The outdoor launchpads for the V-2 rockets would have been at the end of each passageway. The two passageways were angled at 64° 50' and 99° 50' west of north respectively—not aligned with any probable target but merely permitting the rockets to be transported to either one or the other, of their pair of sufficiently-separated launch pads. [13]

The facility was designed, as was its predecessor at Watten, to receive, process and launch V-2 rockets at a high rate. Trains carrying V-2s would enter the heart of the complex through the Ida rail tunnel, where they would be unloaded. A large number of V-2s could be stored in the side tunnels LOX would also be produced on-site ready for use. When the time came, the rockets would be moved into the octagonal preparation chamber where they would be lifted to a vertical position for fuelling and arming. From there they would be transported on motorised launch carriages, still in a vertical position, through the Gustav and Gretchen passageways. The launch pads were located at the end of the track on the floor of the quarry, from where the missiles would be fired. [14]

The priority target for the V-2s was 188 kilometres (117 mi) away: London, which Hitler wanted to see pulverised by the end of 1943. [4] The Allies were alarmed when an analyst found that part of the complex was aligned within half a degree of the Great Circle bearing on New York, and its equipment was large enough to accommodate a rocket twice the size of the V-2: the "America Rocket", the proposed A10 intercontinental ballistic missile. [15]

Although physically separate, another facility built in nearby Roquetoire was an integral part of the Wizernes complex. Umspannwerk C was built to house a Leitstrahl radio command guidance system which could be used to send course corrections to missiles launched from Wizernes to fine-tune their trajectory during the launch phase. [16]

The Allies first noticed construction activity at Wizernes in mid-August 1943 when the Germans began building railway track and the offloading stores into the old quarry. [17] After Hitler authorised the decision to turn the depot into a missile launch site, construction was stepped up. Work on the dome began in November 1943 [18] and tunnelling in the cliff face below began in December. At the start of January, Allied reconnaissance aircraft observed an elaborate system of camouflage on the hill top, installed to conceal the dome. [17] The building works were greatly hindered by the constant air-raid warnings, which stopped work 229 times in May 1944 alone. In response to Hitler's desire to see the site completed the workforce was expanded substantially from 1,100 in April 1944 to nearly 1,400 by June. [19] About 60% of the workers were Germans skilled workers, such as miners from Westphalia, were recruited to excavate the tunnels and build the dome. [20] The remainder were principally Frenchmen conscripted by the Service du travail obligatoire (STO), plus Soviet prisoners of war. [9] The project was overseen by several large German construction companies, with Philipp Holzman A.G. of Frankfurt am Main and the Grossdeutsche Schachtbau and Tiefbohr GmbH serving as the chief contractors. [21]

One of the most difficult challenges faced by the Germans was constructing the great dome while under regular air attack. The dome's designer, Todt Organisation engineer Werner Flos, devised a plan under which the dome would be built first, flat upon the ground, and the soil underneath it would be excavated so that the construction works below would be protected against aerial attacks. A circular trench was excavated on the top of the hill above the quarry to an outside diameter of 84 metres (276 ft). The dome was built within this trench and the galleries and octagonal preparation chamber were excavated below. [10] [22]

As an additional bomb-proofing method, the dome was surrounded by a bomb-proof "skirt" or Zerschellerplatte of steel-reinforced concrete, 14 metres (46 ft) wide and 2 metres (6.6 ft) thick. This was supported by a series of buttresses, which were not tied into the dome itself, above the entrances to the Gustav and Gretchen tunnels. Another concrete structure was tied into the skirt to the north-west of the dome, which was perhaps intended for use as an observation and control tower. A separate underground building was constructed on the western side of the quarry to serve as a hospital and as offices for the engineers. [23] A Decauville narrow-gauge railway was installed on the quarry floor to transport supplies from the main line to the construction site. [24]

A cube-shaped concrete building was constructed on the top of the hill, next to the dome. This was intended to be used as the bomb-proof outlet for a ventilation and air conditioning shaft. It was an essential component of a facility where dangerous and explosive gases were expected to be used in large quantities on a daily basis. It was never finished, and the Allies found when they captured the site that the ventilation shaft had not been fully excavated. The building survived the bombing intact and is still prominently visible today. [23]

Unlike its sister site at Watten, there was no on-site power plant. Electricity at Wizernes was provided by a connection to the main electric grid, with power consumption estimated at between 5,000 and 6,000 kVA. [21]

The Allies became aware of the Wizernes site in August 1943 when the Germans began laying extensive new rail sidings which were spotted by RAF reconnaissance flights. [10] Late 1943, a Belgian, Jacques de Duve, supported by German opponents, informed MI5 about the existence of a rocket production site in Saint-Omer. MI5 did not believe de Duve, who was interned for the rest of the war in Latchmere House. [25] In November 1943, the Allied Central Interpretation Unit reported that the Germans had begun constructing the concrete dome and were undertaking tunnelling works in the east face of the quarry. However, it was not until the following March that the Allies added the site to the list of targets for the bombing campaign against V-weapon sites that had already wrecked the Watten bunker and numerous V-1 flying bomb launching sites. Over the next few months, the USAAF and RAF carried out 16 air raids involving 811 bombers that dropped some 4,260 tons of bombs. [16] The bombing caused destruction across a wide area, killing 55 residents of the nearby village of Helfault. [26]

Conventional bombing raids only achieved a single bomb hit on the dome itself, causing negligible damage. However, in June and July 1944 the RAF began attacking the site with 12,000 pounds (5,400 kg), ground-penetrating Tallboy bombs. [16] The external construction works were completely wrecked by the bombing and one Tallboy landed just beside the dome, blowing out the entire quarry cliff face and burying the entrances to the Gustav and Gretchen tunnels. The entrance to Sophie was also buried, leaving Ida as the only entrance to the facility. The dome was unscathed but the buttresses supporting the protective Zerschellerplatte were dislodged and slid partway down into the quarry. Serious damage was also caused to the tunnels beneath the dome. The damage made it impossible to continue work on the site. Dornberger complained: "Persistent air attack with heavy and super-heavy bombs so battered the rock all around that in the spring of 1944 landslides made further work impossible." [27] His staff reported on 28 July 1944 that, although the dome had not been hit by the Tallboys, "the whole area around has been so churned up that it is unapproachable, and the bunker is jeopardised from underneath." [27]

Although three launch battalions were formed by the Germans in late 1943, [28] they never got the chance to deploy to the V-weapons launch sites at Watten and Wizernes. On 3 July 1944, the Oberkommando West authorised the cessation of construction at the heavily damaged sites. On 18 July 1944, Hitler abandoned plans for launching V-2s from bunkers [29] and authorized the downgrading of the Wizernes bunker to make it a LOX production facility. [30] However, these plans were overtaken by the Allied liberation of Northern France following the Normandy landings. The site was finally abandoned a few days before the Allies reached it at the start of September during the rapid liberation of the area by British, American, Canadian and Polish troops. [31] British engineers inspected it on 5 September. [32]

Shortly after the Wizernes site had been captured in September 1944, Duncan Sandys, the head of the British "Crossbow Committee" investigating the V-weapons programme, ordered the constitution of a Technical Inter-Services Mission under Colonel T. R. B. Sanders. It was given the task of investigating the sites at Mimoyecques, Siracourt, Watten, and Wizernes, collectively known to the Allies as the "Heavy Crossbow" sites. Sanders' report was submitted to the War Cabinet on 19 March 1945. [33]

The purpose of the Wizernes site had been unclear prior to its capture but Sanders was able to deduce its connection with the V-2 from the dimensions of the complex and some intelligence information that his team had been able to retrieve. Sanders' report concluded that it was "an assembly site for long projectiles most conveniently handled and prepared in a vertical position". He conjectured the approximate length of the projectiles from the height of the Gustav and Gretchen tunnels, though he noted that there was some doubt about the height of the doors at the tunnel entrances. Segments of the doors had been recovered from a storage dump near Watten railway station, but were incomplete. Judging from the size of the tunnel entrance, the maximum size of the projectile could have been between 17 metres (56 ft) and 24 metres (79 ft) in length and 4 metres (13 ft) in breadth. [34] (This was substantially larger than the V-2, which measured 14 metres (46 ft) long and 3.55 metres (11.6 ft) wide.) Two witnesses interviewed by the Sanders team reported "an intention of firing a projectile 18 metres long". [21] Sanders noted that "the dimensions of the site make it suitable for the A.4 (V-2) rocket, but the possibility of a new rocket up to half as long again as the A.4 and twice the weight cannot be ruled out." [21] [Notes 1] He concluded that much of the site was becoming unsafe due to the progressive collapse of timbering and recommended that the tunnels and workings under the dome should be destroyed to prevent subsequent accidents or misuse. [24]

The site reverted to private ownership after the war. As the quarry had long since been worked out, it was abandoned. [22] The tunnels were not destroyed but were sealed off, though at some point they were reopened by local people and could be entered the octagon remained sealed off with a ceiling-to-floor barricade. The quarry itself remained in almost the same condition as it had been in 1944, with sections of railway track still in place on the quarry floor. The hospital section remained relatively intact and was used by the local gendarmes as a shooting range. [24]

In 1986, the Espace Naturel Régional in Lille earmarked 10 million francs to develop the site as a tourist attraction for the Nord-Pas-de-Calais region with the intention of establishing a World War II museum there. The plan was publicised in a special open weekend on 20–21 June 1987, attended by over 20,000 people, in which the dome's designer Werner Flos met Professor Reginald Victor Jones, a surviving member of the "Crossbow Committee", at Wizernes. The Ida tunnel and side chambers were opened to the public and used for an audio-visual exhibition of the site's history. [22]

Local historian Yves le Maner was charged with the task of developing the project while a feasibility study was conducted into the possibility of completing some of the original excavation work to make the site safe for public access. The plans were approved in 1993 and the site was purchased by the Commune de Helfaut. The following year, the Conseil Général du Pas-de-Calais acquired the site. The 69-million-franc project (£7.5 million at 1997 prices) was largely underwritten by the Conseil Général, which provided 35 million francs, with another 17 million coming from the regional council. The European Union provided a further 12 million, the French State provided 3 million and the Saint-Omer municipal administration funded the remaining 1 million francs a number of private shareholders were also involved. The Societé d'Equipement du Pas-de-Calais was contracted to carry out the development work, which involved excavating a further two metres (six feet) beneath the dome, clearing out and completing the unfinished concreting of some of the tunnels, building an exhibition centre and car park in the quarry floor and installing a lift to carry visitors up from the octagon to the dome. [1]

The museum opened in May 1997. Visitors enter and leave through the Ida railway tunnel, though the rails have been removed and the floor levelled. Short branch tunnels lead off on either side originally used for storage, they now display wartime objects. Headphone stands along the way present multi-lingual accounts of the construction and purpose of the facility. The tour continues along the Mathilde tunnel to reach a lift that has been installed to bring visitors up to the space beneath the dome, where the main exhibition area is located. [35] Focusing on the story of the V-weapons, life in occupied France, and the conquest of space after the war, the tour presents audio-visual displays in English, French, Dutch and German. The museum houses a large number of original artifacts including a V-1 provided by London's Science Museum and a V-2 provided by the Smithsonian Institution, [1] and incorporates a memorial to the 8,000 people who were shot in or deported from the Nord-Pas-de-Calais region during the war computer terminals track the paths of several hundred of the deportees. [36] In 2011, the museum welcomed 120,000 visitors. [37] In July 2012, the museum opened a planetarium as part of Cerendac, a newly established Centre de ressources numériques pour le développement de l'accès à la connaissance (Resource Centre for the development of digital access to knowledge). The €6 million centre is funded by the Pas-de-Calais department, the Nord-Pas-de-Calais region, the French state, the European Union and the intercommunality of Saint-Omer. [38] Since 2010, the museum has also managed the V-3 site of the Fortress of Mimoyecques. [39]


The A-4 ballistic missile (referred to as the V-2 from September 1944) was developed by the Germans between 1939 and 1944. It was regarded by Adolf Hitler as a Wunderwaffe (wonder weapon) that he believed to be capable of turning the tide of the war. Its operational deployment was restricted by several factors. Large supplies of cryogenic liquid oxygen (LOX) were required as the oxidizer to fuel the missiles. LOX evaporates rapidly, necessitating a source reasonably close to the firing site in order to minimise loss through evaporation. Germany and the occupied countries did not at that time have sufficient manufacturing capacity for the amount of LOX required for a full-scale A-4 campaign the total production capacity in 1941 and 1942 was about 215 tons daily, but each A-4 launch required about 15 tons.

As the missile was intended for use against London and southern England, [8] its operational range of 320 kilometres (200 mi) meant that the launch sites had to be located fairly close to the English Channel or southern North Sea coasts, in northern France, Belgium or the western Netherlands. This was within easy reach of the Allied air forces, so any site would have to be able to resist or evade the expected aerial bombardments. [4]

Various concepts were mooted for the A-4's deployment in a March 1942 study by Walter Dornberger, the head of the A-4 development project at the Peenemünde Army Research Center. He suggested that the missiles should be based in heavily defended fixed sites of a bunker-style design similar to the massive submarine pens then under construction in occupied France and Norway. The rockets could be stored in such sites, armed, fuelled from an on-site LOX production plant, and launched. This offered significant technical advantages not only would the LOX loss be minimised, but the complex process of pre-launch testing would be simplified. A high rate of fire could be sustained as the facility could effectively operate like a production line, sending a steady flow of missiles to the launch pads. [4]

The submarine pens and other Atlantic Wall fortifications had been built in 1940 and 1941, when the Germans had air superiority and could deter Allied air attacks. By 1942 this advantage had been lost to the United States Army Air Forces, which had begun deploying to England in May 1942, [9] and a greatly expanded Royal Air Force. [10] The German Army preferred an alternative approach which would use trailer-style mobile launch platforms called Meillerwagen accompanied by testing and fuelling equipment mounted on railway cars or trucks. Although this configuration was far less efficient and would have a much lower rate of fire, it would have the great advantage of presenting a much smaller target for the Allied air forces. The Army was not convinced that fixed bunkers could resist repeated air attacks and was particularly concerned about the vulnerability of the launch sites' road and rail links, which were essential for resupplying them with missiles and fuel. [4]

In November 1942, Hitler and Minister of Munitions Albert Speer discussed possible launch configurations and examined models and plans of the proposed bunkers and mobile launchers. Hitler strongly preferred the bunker option, though he also gave the go-ahead for the production of mobile launchers. Two different bunker designs had been prepared: the B.III-2a design envisaged preparing the missile for launch inside the bunker, then transporting it outside to a launch pad, while the B.III-2b design would see the missile being elevated from within the bunker to a launch pad on the roof. [11]

Speer gave orders that two bunkers were to be constructed by the Organisation Todt construction group to a "special fortification standard" (Sonderbaustärke), requiring a steel-reinforced concrete ceiling 5 metres (16 ft) thick and walls 3.5 metres (11 ft) thick. They would be built near the coasts opposite England, one on the Côte d'Opale near Boulogne-sur-Mer and the other on the Cotentin Peninsula near Cherbourg. Each would be capable of launching 36 missiles a day, would hold sufficient supplies of missiles and fuel to last three days, and would be manned by 250 troops. [4]

In December 1942, Speer ordered Peenemünde officers and engineers (including Colonel Gerhard Stegmair, [12] Dr Ernst Steinhoff and Lieutenant-Colonel Georg Thom) to tour the Artois region in northwest France and locate a suitable site for an A-4 launch facility. The site chosen was just to the west of the small town of Watten, [13] in the Forest of Éperlecques, near Saint-Omer in the Pas-de-Calais department. [14] It was given the cover name of Kraftwerk Nord West (Northwest Power Plant). [4] [5] [15]

The location was conveniently close to the main railway line between Calais and Saint-Omer, the canalised River Aa, main roads and electric grid lines. [16] Situated 177 kilometres (110 mi) from London, it was far enough inland to be safe from naval guns and it was sheltered to an extent by a ridge that rises to a height of 90 metres (300 ft) to the north. [17]

At nearby Saint-Omer, there was a major Luftwaffe base which was capable of providing air defence for the area. There were existing gravel and sand quarries as well as cement works in the vicinity, which would help with the enormous amount of material that would be needed for the construction works. The quantities required were very substantial indeed 200,000 tons of concrete and 20,000 tons of steel would be required to build the facility. [3] When US Army Major General Lewis H. Brereton inspected the site after it had been captured by the Allies, he described the bunker as "more extensive than any concrete constructions we have in the United States, with the possible exception of Boulder Dam." [18]

The Watten bunker was to be built to a design based on the B.III-2a bunker, though substantially larger. The Germans had originally planned to build a separate LOX plant at Stenay but this option was abandoned in favour of installing a LOX production facility within the Watten bunker. [4]

The bunker consisted of three main elements. The main part of the building was a giant structure some 92 metres (302 ft) wide and 28 metres (92 ft) high, housing the LOX plant and a vault where missiles would be assembled and prepared. [4] Its walls were up to 7 metres (23 ft) thick [3] and the bunker's working levels descended 6 metres (20 ft) below ground. [19] The plant would house five Heylandt compressors, each capable of producing about 10 tons of LOX per day. About 150 tons of LOX were to be stored in insulated tanks on-site. [4] The facility was intended to store up to 108 missiles and enough fuel to supply three days' worth of launches. The Germans planned to fire up to 36 rockets a day from the site. [19]

On the north side of the building was a fortified standard gauge railway station, linked to the main Calais-Saint-Omer line at Watten via a 1.2 kilometres (0.75 mi) spur line. Missiles, warheads and other components would be shipped to the station and transported on trucks into the main area of the bunker. Here the rockets were to be assembled, raised into a vertical position and fuelled and armed. From the arming halls, they would be moved to either end of the building through pivoting doors 18 metres (59 ft) high. They would exit through the south face of the building and would be moved on tracks to the launch pads. There were no doors on the exit portals so chicanes were installed in the exit passage to deflect the blast of rockets being launched from outside. [20] Launches would be overseen from a command tower located in the centre of the south side of the bunker, overlooking the launch pads. [4]

To the north of the bunker, the Germans erected a bomb-proof power station with a 2,000 horsepower (1.5 MW) generating capacity. The site was initially powered from the main electricity grid, but it was intended that it would have its own independent power source to minimise the likelihood of disruption. [21] Also associated with the Watten complex was a radar tracking site at Prédefin, 29 kilometres (18 mi) south of Saint-Omer. A Giant Würzburg radar system was installed there to follow the trajectories of V-2s being launched from Watten. The intention was to follow the trajectory for as long as possible so that the accuracy of the missile launches could be determined. [22]

The site was designed in January and February 1943 by engineers from the Peenemünde research facility and the Organisation Todt. [23] On 25 March 1943 the construction plans were presented to Hitler, who immediately gave the go-ahead for the project to begin. [16] The construction firm Holzman & Polanski was awarded the contract [24] and 6,000 workers from Building Battalion 434 started construction that same month [23] using plans by Franz Xaver Dorsch, Construction Director at the Organisation Todt. [3] [13] [25] It was envisaged that the structure would be ready by the end of July 1943, though not its wiring and plant, and it was intended that it would be fully operational by 1 November 1943. [16]

The workforce consisted of a mixture of German specialists and forcibly conscripted Frenchmen from the Service du Travail Obligatoire (STO). They were supplemented by Belgian, Dutch, French, Polish, Czech and Soviet prisoners of war and civilian conscripts, who were used as slave labour. [26] The labour force also included many French political prisoners and Spanish Republicans who had fled to France after General Franco's victory in the Spanish Civil War but had then been interned by the invading Germans. [27] The non-German workers lived in two camps officially known as Organisation Todt Watten Zwangsarbeitslager 62 (Forced Labour Camp 62) [24] about 2 kilometres (1.2 mi) distant from the site, near the village of Éperlecques.

The camps were guarded by the French civil police with the assistance of Belgian and Dutch Nazis and Russian POWs who had volunteered for guard duty. Although escape attempts were punished by immediate execution, there were up to three escapes daily with external assistance. The commandant of the camp is said to have complained that it would have been easier to "guard a sack of fleas". [24] Over 35,000 foreign workers passed through the camps during the period in which they were operational. [26]

The labourers worked in 12-hour shifts of 3,000–4,000 men, with three 20-minute breaks during each shift. The work continued around the clock, seven days a week, under giant floodlights during the night. The living and working conditions were extremely harsh, especially for the political prisoners and the eastern Europeans, who were given especially punitive treatment due to their status as the most expendable members of the workforce. [28] For the non-German workers, falling ill or being unable to work through injury was the equivalent of a death sentence, as they would either be left to die or be transported back to the concentration camps from which they had been brought. [26] A German commission that inspected the labour camps in the area in late 1943 commented: "The Eastern [European] worker is very tough. He works at his job until he falls flat on his face in the mire, and all that is left for the doctor to do is to issue the death certificate." [29]

A large supply dump was established at Watten next to the River Aa. This site was eventually used to store material required for all the V-weapon sites in the Saint-Omer area. [21] Building materials were brought there by barges and trains where they were unloaded onto a Decauville narrow-gauge railway for transportation to the construction site, where concrete mixers operated day and night. [23] A 90 kV power line running to a transformer at Holque north of Watten provided electricity. [21] An old quarry at Wizernes codenamed Schotterwerk Nordwest (Gravel Quarry Northwest), some 12 kilometres (7.5 mi) south of Watten, was also converted into a storage dump to supply the Watten facility. [30]

In early April 1943, an Allied agent reported "enormous trenches" being excavated at the Watten site, and on 16 May 1943 an RAF reconnaissance mission led to Allied photographic interpreters noticing unidentified activity there. [31] Other large facilities were observed to be under construction elsewhere in the Pas-de-Calais. The purpose of the construction works was very unclear [32] Lord Cherwell, Winston Churchill's scientific adviser, admitted that he had little idea what "these very large structures similar to gun emplacements" were but he believed that "if it is worth the enemy's while to go to all the trouble of building them it would seem worth ours to destroy them." [33]

At the end of May, the British Chiefs of Staff ordered that aerial attacks be carried out against the so-called "heavy sites" being built by the Germans. [2] On 6 August, Duncan Sandys, who headed a high-level Cabinet committee to coordinate the British defence against the German V-weapons, recommended that the Watten site should also be attacked because of the progress being made in its construction. [34] The British Chiefs of Staff noted that a daylight attack by US bombers was under consideration but they raised objections to the proposal, as the Air Staff thought that Watten had nothing to do with rockets, suggesting that instead it might be merely a "protected operations room". [34]

The timing of the first raid was influenced by advice given by Sir Malcolm McAlpine, the chairman of the construction company Sir Robert McAlpine, who suggested that the Watten site should be attacked while the concrete was still setting. On 27 August 1943, 187 B-17 Flying Fortresses of the US 8th Air Force attacked the site with devastating effect. The fortified train station on the north side of the bunker was especially badly damaged, as concrete had just been poured there. Dornberger later wrote that following the attack the site was "a desolate heap of concrete, steel, props and planking. The concrete hardened. After a few days the shelter was beyond saving. All we could do was roof in a part and use it for other work." [33] The bombing killed and injured hundreds of the slave workers on site although the Allies had sought to avoid casualties by timing the raid with what they thought was a change of shifts, the shift pattern had been changed by the Germans at the last minute to achieve the day's work quota. [35]

Only 35% of the Watten bunker had been completed by this time. [10] It was clearly no longer possible to use it as a launch site, but the Germans still needed LOX production facilities to supply V-2 sites elsewhere. After surveying the site in September and October 1943, Organisation Todt engineers determined that the northern part of the facility was irretrievably damaged but decided to focus on completing the southern part to serve as a LOX factory.

One of OT's engineers, Werner Flos, came up with an idea to protect the bunker from bombardment by building it up from the roof first. [36] This was done by initially constructing a concrete plate, flat on the ground, which was 5 metres (16 ft) thick and weighed 37,000 tons. It was incrementally raised by hydraulic jacks and then supported by walls which were built underneath it as it was raised, becoming the roof. The resulting concrete cavern was intended to be used by the Germans as a bombproof liquid oxygen factory. The thickness of the roof was chosen on the assumption that Allied bombs were incapable of penetrating such a depth of concrete the Germans, however, were unaware of the British development of earthquake bombs. [33]

The Germans' main focus of attention switched instead to Schotterwerk Nordwest, the former quarry at nearby Wizernes, where work had been ongoing to build a bombproof V-2 storage facility. This project was expanded to turn the quarry into a fixed launch facility. Plans were put into effect to build a huge concrete dome – now open to the public as the museum of La Coupole – under which missiles would be fuelled and armed in a network of tunnels before being transported outside for launching. [20] The Allies carried out further heavy bombing against both the Watten and Wizernes sites with little initial effect on the buildings themselves, although the rail and road network around them was systematically destroyed. [37]

On 3 July 1944, Oberkommando West gave permission to stop construction at both sites, which had been so disrupted by bombing that work could no longer proceed. [2] Three days later an Allied raid succeeded in wrecking the interior of the Watten bunker with a Tallboy bomb that brought down part of the roof. [38] Finally, on 18 July 1944, Hitler decreed that plans for launching missiles from bunkers need no longer be pursued. [39] Dornberger's staff subsequently decided to continue minor construction at Watten "for deception purposes". The site itself was now useless, as the Germans recognised when they wryly codenamed it Concrete Lump, and the liquid oxygen generators and machinery were transferred to the Mittelwerk V-2 factory in central Germany, well away from Allied bombers. [40]

The Watten site was captured on 4 September 1944 by Canadian forces. The Germans had evacuated it a few days earlier and removed the pumps which kept the cavernous basement free from water not long afterwards it began to flood. This made a substantial amount of the bunker inaccessible to the Allies. [41]

The bunker was inspected on 10 September 1944 by the French atomic scientist Frédéric Joliot-Curie, accompanied by Sandys. [3] Following the visit, Sandys ordered a Technical Inter-Services Mission under Colonel T.R.B. Sanders to investigate the sites at Mimoyecques, Siracourt, Watten, and Wizernes, collectively known to the Allies as the "Heavy Crossbow" sites. Sanders' report was submitted to the War Cabinet on 19 March 1945. [42]

Despite the capture of Watten, it was still not known at this time what the site had been intended for. Sanders noted that "the purpose of the structures was never known throughout the period of intensive reconnaissance and attack". [43] Based on the discovery of large aluminium tanks installed in the main part of the bunker, he opined that the Germans had intended to use it as a factory for the production of hydrogen peroxide for use in the fuelling of V-1 and V-2 missiles. He ruled out the possibility that it could have been used for LOX production and concluded, erroneously, that "the site had no offensive role." [44] He recommended that (unlike the Mimoyecques and Wizernes sites) the Watten bunker presented no threat to the UK's security and "there is thus no imperative need, on that account, to ensure the destruction of the workings." [45]

The bunker was targeted again by the Allies in February 1945, this time to test the newly developed CP/RA Disney bomb – a 4,500 lb (2,000 kg) concrete-piercing rocket-assisted bomb designed to double the normal impact velocity, and thereby increase the penetration, of the projectile. [46] The site had been chosen for testing purposes in October 1944 as it had the largest accessible interior area of the targets under consideration and was furthest from an inhabited town.

On 3 February 1945, a B-17 of the US Eighth Air Force dropped a Disney bomb on the Watten bunker and scored a hit over the wall section, but the results were inconclusive and the Air Force was not able to determine how well the bomb had penetrated the concrete. Although Disney bombs were used operationally on a number of occasions, the weapon's introduction came too late to be of any significance in the war effort. [47] In January 2009 the body of the Disney bomb was extracted from the roof, where it had embedded itself. [48] [49]

The Watten bunker was inspected again on 20 June 1951 by an Anglo-French commission to determine whether it was capable of being reused for military purposes. The British Assistant Military Attaché, Major W.C. Morgan, reported to the Director of Military Intelligence at the War Office that the main part of the bunker had not been significantly damaged by bombing and that although it was flooded, if it was patched and drained "the building could be quickly made ready to receive oxygen liquifying plant machinery, or for any other purpose requiring a large and practically bomb-proof building." [50]

No further military use was made of the bunker and the land on which it stands reverted to private ownership. It was left abandoned for many years before the owners decided to redevelop the site. In 1973, the bunker was opened to the public for the first time under the name of Le Blockhaus d'Éperlecques. The ownership was taken over by Hubert de Mégille in the mid-1980s [51] and on 3 September 1986 the French state declared it a monument historique. [7] The area around the bunker has been re-forested, though it is still heavily scarred by bomb craters, and various items of Second World War military equipment (including a V-1 on a launch ramp) are on display alongside paths around the site. An open-air trail leads to and around the bunker with interpretative signs posted at various points to tell the story of the site and the German V-weapons programme. In 2009, the museum welcomed 45,000 visitors. [51]

62 thoughts on &ldquo The Nazi Nuclear Program – How Close Were the Nazis to Developing an Atomic Bomb? &rdquo

This article’s analysis is reasonably correct yet there are still surprises to come out of the archives.

For example a team of scientists from Vienna worked for Kammler’s SS Fuhrungsstab B-9 at Melk on what appears to have been both an enrichment plant and a reactor design which did not require heavy water.

In March 1944 Harteck, Jensen and Heinz-Hocker ordered uranium for two reactors which there is no record were ever built.

One the G-III appears to have involved 1.6t of light water as a moderator and using uranium fuel rods rather than cubes. The other, the G-II was a low temperature reactor with parrafin. moderator, cooled by Methyl Butene.

Also Dr Harteck built two cenrtrifuge enrichment plants, Dr Bagge built an isotope sluice enrichment plant and Dr Martin appears to have developed a centrifuge which used heating & cooling to create convective currents within a centrifuge, by a method now associated with the Zippe centrifuge. No records of Dr Martin’s work exist in the public domain, but my personal hunch is that this was one of the two underground nuclear projects at Melk.

There was also another project in Silesia often referred to as the Nazi Bell developed by Heinz Ewald to either breed Uranium from Thorium, or enrich Uranium in a homogeneous plasma field generated by mercury.

Because we still don’t know what we don’t know about these other projects which remain cloaked in WW2 secrecy, it isn’t safe to say the Nazis fell short of enriching enough uranium for a bomb. Some ALSOS documents remain top secret to this day.

Claims that a nuclear weapon was tested at Rugen in October 1944 and again at Ohrdruf in March 1945 leave open a question, did they or didn’t they?

Dear Mr Gunson, I read with interest you article on heavy water production in Germany during the war. My father worked in one which was built into an alpine mountain. I dont think anyone knows about this site now. Do you know anything about it. I would love to discover its exact location. Regards, Paul Strausa

Dear Paul, no I have not heard of your father’s facility however i would be interested to learn any further clues you could pass on please?

I am aware from the son of Polish Jewish concentration camp prisoner from a camp near Hannover about a hidden underground Heavy Water facility there.

What I am aware is that from mid 1942 the German firm BAMAG Meguin AG produced improved Pechkranz electrolysers to replace the existing ones at Vermork and then installed 9 further electroiysers at Saheim near vermork.

Then The Germans under the leadership of Dr Wilhem Suess and Dr Paul Harteck had further Pechkranz electrolyzers installed at two Montecatini electrolytic plants in Italy, one near Merano and the other at Cotrone, in the Tyrol.

Unless you have more specific information my guess would be that the alpine facility you mention is either at one of those two locations or if in Austria somewhere in rail contact with these two Italian plants.

I do know the Nazis had a nuclear facility at Zell am See in the Tyrol not far from Hitler’s retreat at Berteschgarten. This was an SS facility. In September 1944 the SS wanted establish a Tritium facility for thermonuclear weapons. The Zell am See facility was controlled by the SS 13th division I understand.

There is one other underground Heavy Water facility which Dr Karl Wirtz was involved with and that was in Silesia.

Few people realise that after the sinking of the Hydro ferry at Lake Tinnso in Norway, claiming 618kg of Heavy Water (Deuterium) Dr Harteck had a further 6,200kg evacuated successfully to Germany by road from Saheim. In total from Norway during the war Germany repatriated 7,120kg of heavy water from Norway..

I hope you will post again Paul with anything further you can tell us of your father’s experience?

I think it is important to fill in the gaps in our historical record which were left blank for reasons of post war political sensitivity.

Hi Simon I was amazed by your response because I think he probably worked in Zell am See and this has massive personal significance for me. I will briefly try to tell you what i know and maybe you could add further and respond. I am very interested to piece together where my father was during the war, My father joined the german army in 1943 when food became scarce and in doing so ensured accommodation and food for his family, He had a wife and child. I believe he worked at this site probably as a carpenter, which was his trade. I suspect that everyone that worked there were in the army. Maybe you can tell me different. He told me that from above you would nt know the plant was there because it was built into the side of a mountain so it was never bombed. All the pipe work was gold to facilitate production. When bombing in the area rendered the plant inoperable he was then involved in the defence of hungary. When things got out of control and the german army was in disarray, he and some friends liberated an ambulance and drove it to the site to se if they could get their hands on the gold. However, when they got there it had all gone and they were told that the SS had taken it all – which fits in with your understanding. He was eventually captured by the americans and placed in a prisoner or war camp near Saltzburg – which fits in with the location I guess. I would be very interested to find out any more informations you may have about the plant how it was run etc. Is it possible to trace him there as a member of the military workforce? Look forward with great anticipation to your response. Paul

Maybe I was mistaken which SS Division was there, perhaps it was the SS 8th Kavallerie Division-Florian at Fischorn castle. I do however recall reference elsewhere to the SS 13th Div. This castle was where Goering attempted to parley with the Americans in the last weeks of the War.

The 8th Division was destroyed at Budapest in 1945 so I suspect your father was not in the Whermacht (army), but rather in the Waffen SS. Possibly he was too embarrassed to tell you everything?

This regiment was also closely associated with Hitler through his SS adjutant SS-Gruppenführer Hermann Fegelein, therefore may have provided guards for Hitler’s retreat.

I make a simple assumption here but possibly the tunnels you refer to were from beneath the castle.

Otherwise I am not entirely sure however the Laboratory of Dr Ing. Mario Zippermayer was in the next town of Lofer.

There is an excellent reference to Goering at Fischorn castle in 1945 by David Irving whose website may be unobtainable in Germany:

I suggest Paul that you try to locate veterans of this division or surviving family to research more for your own peace of mind. If you discover anything further please return and post it for all of us as i would be most interested.

Can you recall if your father referred to a tunnel entrance beneath a castle (Zell am See) or was the entrance in an alpine meadow (Lofer)?

This is great! The only problem is that united states would not have developed the bomb had it not been for Albert Einstein, A GERMAN, who wrote FDR a letter! Shit! We had to beat the germans by usin a german!

Funny, huh? History is full of interesting little twists like that.

Yes but not so funny. Who persuaded Dr. Albert Einstein to write the letter having obtained a secret patent in 1934? Who was Ida Noddack, and when did Italy become an ally of Germany and its anti-semitic policies?
Who made a joke about some fool destroying the universe and publicly said many times that talk of commercializing nuclear energy was nonsense.

As to the notion that Einstein who was a German writing a letter to FDR, which supposedly kick-started the Manhattan Project – this is only partially so.
First of all, Einstein was a Jew from Germany, which is why he had to flee Germany and find new home in the USA.
Secondly, he was urged by others – both physicists and non – to use his authority and this was an accepted point of view that US needs to be ahead of the Axis in develoment of a nuclear weapon.

Thirdly, the fact that Germany fell behind in the A-bomb race was an extension of the NAZI policy in many aspects. Hence, it may be considered as a logiacl consequence of their policy rather than a historical quirck

Einstein played little role in developing the atomic bomb. He was approached by Teller and Szilard in 1939 to write to the Queen of Belgium whom Einstein regularly corresponded with to ask the the Belgian Government not to supply any Uranium from the Congo to Germany. In the event Belgium was invaded the following year and a huge stock was captured anyway. Einstein insisted that protocol demanded sending a letter first to the US State department for clearance to make such a request. Unexpectedly that resulted in an invitation to brief FDR. That is why Einstein declined the credit. He played a cameo role to Teller and Szliard.

Germany did not fall behind USA. According to OSS intelligence reports from Zurich found in the Woods memorandum to Cordell Hull (see Hull papers) there were three underground nuclear tests conducted in the Schwabian Alps in July 1943, near Bisingen/Tubingen where much of the real A-bomb research occurred.

In addition a sports diver using the email name PLouise (possibly Patricia Louise Grey of California) commented some years ago on an online forum that she had dived at a spot 2.5 nautical miles SW of Owls Head, Maine where she recovered the constructors plate from the wreck of a six engined aircraft. The plate came from Junkerswerke indicating it must have been a six engined Ju-390 which is known to have had the range to reach USA. Another contributor replied on the Twelve O’Clock High (TOUCH) forum revealing his family were living at Rockport Maine when a six engined aircraft came down in the sea about 17/18 September 1944. Four drowned Luftwaffe airmen were later recovered from the sea and the incident was hushed up. This has the hallmark of a failed attack on new York with an atomic weapon.

According to a secretly recorded conversation between nuclear scientists at Farm Hall in 1945, it was mentioned USA had threatened Hitler with a nuclear attack on Dresden if he did not sue for peace within six weeks. In August Churchill warned Hitler via Romania’s Marshall Antonescu that the RAF would deliver anthrax spores all over Germany if a single German nuclear weapon was used against the British isles. Rainer Karlsch reveals in his book that in July 1944 Schumann was warned to halt all work on the Nazi atomic bomb.

What happened next was the abortive bomb assassination attempt (Valkarie) against Hitler after which the SS took over the German Army’s atomic bomb project and used it in negotiations. Himler sought an armistice with the western allies so that Germany could continue to fight the Soviets. This would have contravened the Grand alliance signed at San Francisco in 1942 (known as the United Nations) however it seems USA did enter some form of understanding leading to a secret peace deal with the SS.

The Nazis were about 2 years ahead of the Manhattan Project but were threatened with Anthrax attacks before they could prepare a credible stockpile. The German intention was to arm V-2 rockets with 0.5 kiloton yield warheads. A declassified decrypted diplomatic signal from the Japanese embassy in Stockholm in December 1944 referred to the German “Uranium atom splitting weapon” of devastating effect.

The problem is that history has been written wrongly to conceal US double dealing behind the Soviets back in 1944. From the American and British point of view they were trying to buy time and stave off a nuclear attack on England in 1944. This as far as my research leads me is the true story of how WW2 ended.

Simon, regarding your reply to “Timothy”, I find your “alternate history” to be very convincing, and your conclusions dovetail quite well with my own—except that you fill in many of the blanks and connect many of the dots between the general conclusions / suspicions I had arrived at independent of your own, obviously more comprehensive research. Your information about the crash of the six-engined Junkers aircraft is explosive. I had read about this on another website (one of yours, actually) but was not aware that anyone had actually dived the wreckage, much less retrieved any of it and brought it back to the surface. I would LOVE to see your sources, ie, the forums on which the people you mentioned (the diver and the eyewitness family) were writing. If you’d care to disclose that information I’d be grateful.

I had never heard of the underground tests. BTW, I saw the MAGIC intercept you refer to on this site at the top of the discussion thread on another site. I actually went to the National Archives, myself, a couple of months ago, in part on a mission to find that specific document. I found it and photographed it and posted it on the discussion thread. I also developed my own lines of thought and research starting from that point, and reached many of the same conclusions that you have—again, just not with as much specific detail about which SS figures were doing what, and where. I find your thesis quite compelling and find that SS takeover of the end of war ship of state in Germany (the SS running things and not really Hitler himself, anymore) is a very plausible idea. Quite similar to what went on in Japan, at least with the Japanese atomic bomb program on the mainland at the RIKEN Institute, where Army Lt. Colonel (and nuclear physicist) Tatsusaburo Suzuki took direct control of Project NI and booted the previous project head, Dr. Yoshio Nishina, to the curb.

Anyway, yes, I also have suspected for some time now that the US was cutting deals with certain high ranking Germans / SS / Nazis, and that Germany stabbed Japan in the back by trading uranium in some form to the US—uranium that had been bound for Japan but instead probably ended up exploding over Japan in the Little Boy bomb. Lt. Col. John Landsdale (“a notorious old spook”, to use Robert Wilcox’s description of him) maintained prior to his death that the uranium cargo of German submarine U-234 was taken directly to Oak Ridge for processing and assembly into Little Boy. Naturally, the ahem, “mainstream” largely dismisses his on-camera, for the record testimony in this matter, but I don’t and I know you don’t.

So, the picture becomes: Germany has at least a nominal nuclear weapon capability but is deterred from using it by England’s Doomsday device, Churchill’s anthrax bioweapon. Germany realizes it doesn’t have enough nukes to gamble that it can obliterate England (along with any US forces based there or, after the invasion, on the Continent) without being all but annihilated in return by anthrax. So, they have the bomb or some version of it, but can’t make enough of them, fast enough, to win the war. Meanwhile there’s the co-operation with Japan, including at least two uranium delivery missions by submarine that we know of thus far. The last of these missions is heading for Japan when Germany surrenders. Thus, the question now becomes, is post-surrender Germany more likely to benefit from an Allied Occupation, or from risking everything on Japan’s gotterdamerung vs US Operation OLYMPIC in November, 1945? Should Germany send their uranium to Japan and hope that Japanese nukes win the war against the US in the Pacific—and that as a condition of that victory, Germany’s occupation by the Allies is removed—or does Germany stab Japan in the back, essentially throwing in with the Allies in the first act of the Cold War in part as a message to the Soviets? Obviously, if this scenario is correct, Germany or at least West Germany figured (rightly in my view) it would benefit more by allying itself with the US against the Soviets than it would by backing the Japanese with perhaps enough uranium for a couple of bombs—weapons which at best would have caused mass casualties against OLYMPIC but which would not have been enough to overturn the ultimate Allied victory, not could they realistically have been delivered on target against a US city except, perhaps, by kamikaze submarine. Highly unlikely. Thus, Japan, like its two representatives on board U-234, is thrown overboard, the uranium goes to the US, Japan is nuked, West Germany settles into the Allied orbit, the Soviets get the message, The End.

Albert Einstein played no role whatsoever in developing the Atomic bomb for the Manhattan Project, If you believe otherwise please cite his role and a source?

Interesting, but not at all convincing or reassuring. Not trying to do something and running out of time do not amount to impossibility. If Japan hadn’t bombed Pearl Harbor, they would have had more time, and they could have changed their priorities at any time. All it would have taken is one persuasive person to explain the potential of the bomb to Hitler in a way that got him excited. Whether or not the program was a rational use of limited resources would then have become irrelevant.

Hitler was notorious for getting excited over Project A, not seeing results quickly enough, and moving money to Project B. Sometimes the denial of funds to a certain project in the Nazi bureaucracy was due to political / personal reasons. The probability that Germany could have created a nuclear bomb before 1945 was non-existant let’s all be hopeful about that.

This is a side-trail… Albert Einstein, born a Jew, left Germany and renounced his citizenship to become a person without a country, or you could say a citizen of the world among humanity. Only some time after that did he come to the United States to live. Still much later, he decided to become a citizen of the United States, which you could view as a great compliment to what the American system is meant to be.

‘We had to beat the Germans by using a German.’. That is only partly true, as others have pointed out. The Nazis did not consider the Jews to be German. The Nuremberg laws of 1935 revoked Jew’s citizenship, From 1935 on German Jews were no longer citizens of Germany under German law at that time. Einstein had earlier abandoned his citizenship in 1896 but regained it in 1914 when teaching in Berlin. Einstein renounced his German citizenship a second time in 1933 when he left the country for Switzerland. He became an American citizen in 1940.

the bomb came from nazi germany .in theory, it was developed in Grotinger university where openhaimer went to study back in 1926.

The downfall of the drawing displayed above is that the mechanism itself would not work as Plutonium will not explode with a simple gun barrel detonation method. The fission of plutonium is so fast that the fissile material would blow itself apart faster than it could attain critical mass.

The second reason this drawing is fake is that Nazi scientists never called Element 94 Plutonium. German scientists always referred to Plutonium as either Element 94 or as Eka-Osmium.

Sorry but the drawing itself is just a fake

Worth adding about the diagram above that Nazi scientists called Plutonium Eka-Osmium and knew nothing of the name Plutonium given to the element by Manhaatan Project scientists.

The real Nazi atomic bomb is found in the patents of Schumann and Trinks for a bi-conical tactical nuclear weapon with lithium liner hollow charge explosives. In the act of exploding two hollow charges against one another with a fissile uranium 233 target between them, molten slugs of Lithium were smashed against Lithium Deuteride coating the 233U. This caused a Plasma Pinch and the rush of neutrons which resulted plus the intense compression ensured highly efficient chain reaction.The yield however was below 1 kiloton. the warhead weighed just 5 kilograms.

Mr. Gunson, I am guessing you have read Rainer Karlsch’s book Hitler’s Bomb, or else have access to many of his sources. I am familiar with the design you are discussing, but thought there was some question as to whether it actually originated during WWII or shortly after it, as if memory serves the patent to which you are referring was not registered until around 1954, and that (ironically) in France. I am told that the use of U233 would have been because it was easier to produce in bomb-usable quantities from thorium, which was in relative abundance in Europe. This, as opposed to trying to produce U235 from U238. Regarding a gun-type detonation for plutonium, I am told by an acquaintance of mine who has contacts at Los Alamos that a gun-type plutonium bomb is now feasible. During WWII it was probably not, though I’m sure you are aware that the Manhattan Project did produce a number of bomb casings for what would have been called the “Thin Man” bomb, which was a plutonium gun-type design. Thin Man was abandoned in favor of the implosion method “Fat Man”.

Returning to the Schumann – Trinks weapon, is it your opinion that this is what was tested at Ohrdurf? And, was the yield lower because U233, in general, while still usable as an explosive, nevertheless is not as efficient as U235? Or was it more due to the small size of the device? And was that small size what the Germans set out to do from the start, or where they forced into a smaller weapon by scarcity of materials (in particular, of weapons grade uranium of any isotope)?

Hi Will please just call me Simon. I have not been back here since posting so sorry to neglect you. I am not a nuclear physicist, just a passionate historian. I have read portions of Hitlers Bombe, but I struggle to translate. It is a huge shame it is not also printed in English.

As I understand it Dr Walter Trinks a ballistics expert left some 40+ wartime patent applications in his personal papers which Karlsh had access to. Schumann went to the French after the War and taught them the principle of Third generation nuclear weapons (ie boosted fission). This is the same principle adopted by Pakistan, India, Isreal etc.

The Answer is yes I do believe at least two nuclear weapons were tested at Bug Isthmus in October 1944 one at night and another later on 12 October 1944 in daylight witnessed by Luigi Romersa and Rugen resident Elisabeth Mestlin. These were undoubtedly the Schumann Trinks hollow charge device.

This design features a spherical Lithium-6 shell with a vacuum cavity. at the very centre was positioned a small Uranium 233 target coated by a layer of Beryllium oxide and Lithium Deuteride.

When molten Lithium and Deuterium collide at high pressure and temperature they form X-rays which cause a huge neutron flux through the Uranium which replicates the effect of a critical mass.

The nuclear weapon detonated at Ohrdruf in March 1945 however was an adaptation of Dr Ing Mario Zippermayer’s coal dust/liquid oxygen bomb for the SS as part of Operation Hexenkessel. SS Standartenfuhrer Dr Alfred Klemm added radioactive isotopes to Zippermayer’s bomb which increased it’s previous blast radius by factor of ten or more. The isotopes which appear to be added included Uranium dust and a pinkish waxy liquid. I know the SS worked on manufacture of Trittium late in 1944 so I suspect the Ohrdruf bomb had Trittium added. I suspect it used the Fuel Air Effect to gain the compression required to detonate fusion in Trittium.

The Rugen bomb and the Ohrdruf bomb were two different designs.

The Rugen bomb appears from secretly recorded conversations by Dornberger in a British prison camp to be related to an intention to arm the V-2 rocket with it.

The real problem with the Schumann Trinks bomb is the difficulty in scaling up the compression. Deuterium must be compressed uniformly 100-300 times normal density to initiate fusion. The problems rise exponentially the larger the target to be imploded.

The H-bomb however scales up the problem in a manner which the Nazis did not explore. Hope that helps. I will return to answer more later. cheers

Thank you for the highly informative reply, Simon! My initial response is that it looks like they took a typically “German” approach to their bomb design, which is to say, they over-engineered it. In other words they seem to have wanted to leap right over what became first generation atomic fission bombs and move directly to second or even third generation designs (as we now know them), which included some form of nuclear fusion. However, there may have been other factors influencing the direction of their R&D. For example: the widespread and increasingly catastrophic damage to Germany’s industrial infrastructure that was being done by that point in the way by the Allies’ round the clock strategic bombing. Perhaps this meant that more “mundane” materials such as highly enriched uranium were not available or would not be available in sufficient quantities to enable enough bombs to be fielded to turn the tide of the War.

From my point of view, there are a number of problems with what is generally thought to be the “conventional history” of the end of WWII. I have some strong suspicions about some—not all, but some—aspects of that history as it has come down to us. The SS bomb programs are part of what causes me to question some of the standard narrative. I would welcome the opportunity to correspond directly with you about some of this, if you are willing to do so.

Meanwhile, again, I thank you for your reply, sir! Keep up the great work!

One other question comes to mind after re-reading your post. You say that Schumann went to France after the War and basically taught the French “third generation nuclear weapons” or boosted fission bombs. Seems to me I read somewhere that France built the most powerful “pure fission” bombs ever built, with a yield somewhere in the 60kt range. I am guessing this is what you are discussing here? Not to get too far off the topic of the WWII German weapons, but could you give a brief summary of what constitutes second and third generation atomic or nuclear weaponry? And are you following any kind of formal definitions (such as the Manhattan Project’s definition of the explosive power a bomb had to achieve before it was considered a true atomic weapon), or is your description of “third generation” weaponry based on your own broad survey of the history of these bombs?

Hi Will addressing the issue of Uranium 233, this was advocated by Heisenberg at the Harnak Haus conference of june 1942 where the second Uranverin group of relevant scientists was formed. These were a gathering of civil scientists to work on Uranium research. Karlsch uncovered this fact from previously classified KGB files. Heisenberg referred to three methods to developing fissile material for a bomb enriching U235, Element 94 (Plutonium) via a reactor, or “harvesting” Protactinium.

Protactinium is scarce in nature. It is harvested by bombarding Thorium 232 with radiation. Thorium in nature is 99.8% pure Th232, the remainder is harmless Th230. Protactinium 233 forms over an average half life of 22 minutes, then decays over 27 days by itself from Beta decay into virtually pure bomb grade Uranium 233.

If you chemically separate Thorium from Protactinium within 24 hours there will not be any contamination from Pa231, which after re-uptaking another neutron turns into Pa232. This then decays to U232.

U232 is much more spontaneously fissile and in mixture with U233 anything over 0.5% renders it useless for a bomb. It ruins the U233 because it heats the core through Alpha emissions degrading the explosive capability, it becomes to radioactive through Gamma emissions to handle and also risks spontaneous pre-detonation. In reality you need zero ppm U233 to make a worthwhile fissile material.

America struggled after the war to transmute Protactinium into U233 because it used nuclear reactors which have several drawbacks leading to U232 contamination.

The Nazis used cyclotrons (particle accelerators) and had access to them at Paris, Vienna, Copehagen and built one at Heidelberg. They also built at least four Tokamak type Stellerators, one of which was captured at Bisingen by ALSOS. These could transmute Thorium into Protactinium and even Plutonium from Uranium 238 on more powerful machines.

So back to your question Will, yes much easier than enriching U235 and much cheaper too. They did not need a huge Manhattan project. U233 has some drawbacks from U232, but these can be avoided. If so then U233 has all the properties and advantages of Plutonium 239.

It has one more advantage over Uranium 235 which is that in purity of 99.8% which is acheivable with cyclotrons, the critical mass drops to something like a kilogram. For highly enriched U235 (93%) the lowest critical mass is about 54kg. The use of boosted fission also permits sub critical amounts to be detonated.

Also, I read in Carey Sublette’s excellent article “Introduction to Nuclear Weapons Design” on the FAS website that the Schumann – Trinks design was very similar to a detonation mechanism that was used by the United States in some of its weapons. In the US it was known as “the Swan Device”. Sublette claims that no nation has ever fielded a bomb that used U233 for fuel, but I know of at least one US bomb test that used U233. This was a mid-1950s detonation that was part of “Operation Teacup”, so called because the goal was to produce much smaller weapons than those previously built. In any case I am guessing that the WWII German bomb was in fact a U233 device. It would seem that the detonation method used by the Germans works at least as efficiently (if not more so) than any other method, or at least, than any other method of that time. I am not particularly well versed in the state of the art as it stands at present, and so am curious if this particular path is still being pursued. One of the great advantages of the Schumann – Trinks / Swan Device design is that it relies on simple heat to release huge numbers of neutrons from lithium, a substance that begins fissioning at just 900 degrees C. German weapons scientists knew this about lithium as long ago as the 1920s, which is when they achieved considerable success in producing exceptionally high heat through the use of hollow charge explosives. I can’t remember just now where I read about this, and whether it was the German Army or Navy that was doing the experiments, but it seems to me they were able to produce heat well into the thousands of degrees C just with chemical explosives—obviously well above the fission threshold of lithium. Thus the chain of research that led to the Schumann – Trinks design.

Will the methodology of the Swan Device was based on the Schumann Trinks device but instead of coating a fissile target with deuteride, imploded Plutonium into a cavity with a small amount of Trittium (hydrogen-3)

Trittium is yields tenfold more neutrons than deuterium. Otherwise to my knowledge nobody now bothers with Uranium 233 because of it’s inherent problems. Nuclear scientists will not really discuss the advantages but often talk inversely about the risks of nuclear proliferation from pure U233.

Yes the compression of molten hot lithium-6 into Deuterium generates a flash of X-rays which generates a neutron flux through sub-critical fissile targets. Thus with this method even Low enriched uranium or reactor grade plutonium contaminated by Plutonium 240 can still be detonated. that is also the reason why scientists do not want to reveal how Third Generation boosted fission works. The Hiroshima and Nagasaki bombs were big crude First Generation nuclear weapons with designs which are now out of favour.

The letter to FDR was composed by Szilard and co-signed by Einstein, who took no credit for it’s content.

Hey, Simon, I was aware that sub-critical amounts of fissile material could be detonated but prior to reading your information about Schumann-Trinks I did not know exactly how that was accomplished. Essentially this method (among others) creates the same or very similar conditions to what you find in the heart of the first American weapons—but it does so via a completely different route. In order to make fissile material explode, what you need is a supercritical overload of neutrons in the same, highly compressed space as the bomb fuel. Instead of using the uranium or plutonium itself to provide the overload of neutrons that triggers the explosion, the methods you are discussing simply use other materials (deuteride, tritium) that, when stimulated in a particular way, spontaneously “hemorrhage” huge numbers of neutrons in the same immediate locale as the bomb fuel—thereby causing detonation, just via a different triggering mechanism.

Regarding U-233, I was wondering what it was about most production methods that caused it to be less desireable, in some ways, than U-235. I was not aware that it was U-232 as a decay product of proactinium that typically contaminates U-233. A couple of questions occur to me. First, is it the U-232 that emits the alpha and gamma radiation that makes U-233 so hard to use, or is it the U-233 itself, or both elements? Carey Sublette’s extremely thorough article has an extensive section on U-233, and he stated that the problems with contamination from other elements could be solved, but that even after removing these elements, U-233 was still more fiercely radioactive than U-235 or P-239 and thus fabricating a bomb from it was more difficult—though not impossible, as Operation Teacup proved. Is it your understanding that bomb fabrication with U-233 was not pursued any further than Teacup (as far as we know) because the American methods of U-233 production—presumably breeder reactors—left too many impurities in the finished product, or was it because the U-233 even after impurities were removed is dirtier and more dangerous to work with and not worth the trouble when enough U-235 and P-239 was available? As for the German methods, yes, cyclotrons could be used to produce U-233 from Th-232, and I know that the Manhattan Project used cyclotrons to produce “exceptionally pure” P-239, but only in laboratory quantities. Are you saying that the German methods were able to produce more than laboratory quantities of U-233? Were these methods truly suitable for mass production of bomb fuel? Any specific information about the amount that actually was produced, and about the amounts that could have been produced in an industrial setting via the German methods? And, why would the proactinium-231 need to be separated (I presume via chemical means) from the U-233 within 24 hours after being created from Th-232? I’m guessing because proactinium-231 must have a very short half life, and thus you have to get rid of it quick, before it goes through the decay chain you describe and ends up as U-232. Is U-232 contamination the only drawback to U-233, or are there other problems? Sublette was fairly enthusiastic about U-233’s properties as potential bomb fuel, and I agree with him. It is closer to plutonium in its properties and of course, like plutonium, is much easier to mass produce than is U-235. So it would seem on the surface of things to be a much more logical route to take, assuming the impurities can be removed to a sufficient extent.

Having said all of that, the ability of modern weapons to detonate much smaller than critical mass amounts of fissile material makes this line of thinking not irrelevant, certainly, but less relevant than it once was. Basically any kind of bomb fuel will do if you want a tactical or small strategic weapon and have sufficient knowledge of physics, chemistry and metallurgy, unless you are going for a top of the line weapon, ie, 100kt or more. In that case the engineering must be far more precise and complex. But not for smaller weapons. BTW, India is almost certainly taking a close look at weaponization of U-233 because of their plans to utilize the thorium fuel cycle in many of their nuclear power plants.

First of all will just send me a friend request and an introductory note on facebook to “sy gunson” if you want further communication.

No it is not quite as simple as generating a large neutron flux… that is half the story. The other half is you have to also compress the deuterium at the same time by a factor of 100-300 times normal (variation according to different factors). Because heavy hydrogen takes up a lot of volume you get a huge rush of neutrons (deuteron beam) but to get any worthwhile yield requires igniting some compact fissile material too (ie Uranium or Plutonium) The density of Uranium allows a smaller warhead.

First Generation nukes include the Hiroshima Mk.1 bomb and Nagasaki Mark III bomb. They are first generation because they rely on attaining natural critical mass. Starting with the mark IV bomb in 1948 there was a shift towards boosting with Trittium inside a hollow sphere of barely subcritical Plutonium called a Christie core, but still in essence a reliance on critical mass.

Second generation was the use of conventional Plutonium implosion A-bomb to trigger a Hohlraum (a long tapered tube to amplify a plasma shockwave in deuterium) hence the name Hydrogen bomb. This was the so called “super” design which Teller worked on at Berkley from 1942.

The next step was in 1952 with development of fusion boosted fission of sub-critical fissile masses. This drew from the tutoring of Dr Kurt Diebner head of the WW2 German Army Ordnance A-bomb project which fostered the Schumann Trinks weapon. There are many variation of this theme now and these weapons can substitute uranium or plutonium for the fissile mass and the isotopic purity is not a critical factor because the rush of neutrons at detonation is so great it doesn’t matter.

The Schumann Trinks weapon imploded Lithium-6 towards a deuteride coated Uranium 233 target. With Deuterium the neutrons are emitted away from the plasma striking it, therefore are directional and can be directed at the Uranium.

With Trittium the neutrons emitted are multi-directional (ie in all directions) therefore the best method to capture trittium neutrons is to enclose the trittium in a hollow shell of Plutonium etc. .

Sublette’s comments about U233 contamination with respect are still based around harvesting Protatcinium 233 from a breeder reactor. there the issue is that Pa233 is formed in just 22 minutes H/L however if fetile thorium is not removed and separated within 25 hours Thorium 231 may be formed and start uptaking another neutron to become U232.

The other way U232 forms is the neutron decay of Uranium 233 back into Uranium 232, in each case from extra unwanted radiation activity. the extra radioactivity in a nuclear reactor cannot be prevented.

In a cyclotron (particle accelerator) however the exposure is limited and chemical separation within 24 hours will prevent formation of U232 altogether, thus one can obtain either zero or near zero parts contamination per million. in zero ppm contaminated U233 the material is no more difficult than weapons grade Plutonium 239.

Even in the purest U233 eventually over decades indigenous U232 will begin to form, but this is managable.

The German scientist prof Baron Manfred von Ardenne Ardenne believed, that he could enrich 1.5 g Uranium 235 up to 15% in an hour with his Betatron. US Calutron operation for Manhattan produced 100 g daily of 10% enriched. Uranium 235.

In terms of U233 you are not enriching rather radiating Thorium, from hints i have read i would expect half a kilogram (1lb) per day in the right apparatus was possible. If chemically separated from the Thorium immedfiately it would naturall decay into uranium 233 over a month or so. You could repeat the same process each day. The nazis were far more interested in Thorium seized from France in 1944 and monazite sands from the Black Sea coast than they were in enriching Uranium 235.

India and Pakistan now both use third generation nukes to trigger H-bombs in the missiles. If you take a small third generation boosted fission nuke to ignite a secondary Hohlraum filled with deuterium there is no real limit to the megaton yield. The W78/mk12 warhead used on the minuteman III missile uses Lithium/Deuterium boosted fission to detonate a Hydrogen bomb secondary to obtain 330kt yield.

I have to read the rest of your post to check what i have failed to answer but none of this technology except the H-bomb secondary was beyongd the nazis in WW2. The Germans wanted a small yield warhead for the V-2 rocket originally. The SS somehow adapted Zippermayer’s coal dust Fuel Air Explosive to create a nuke towards the end which had a 4.5 kilometre blast radius. Prior to this the same Zippermayer bomb using just coal dust and liquid oxygen had a blast radius of just 600m when tested in August 1943.

U233 contaminated by U232 is hard to use because of several issues. Spontaneous fission of U232 can pre-initiate a nuclear explosion causing a fizzle where the U232 burns before a chain reaction can occur in the U233. Next issue is the alpha emissions from U232 act to heat the core which decreases the neutron density, thus again degrading yield. Next issue is gamma emissions which make the warhead too dangerous to handle. U233 with 0 ppm U232 will emit less Gamma radiation than weapons grade Plutonium. The more contamination the more Gamma emissions. With 0.4% U232 contamination after fifteen years the Gamma emissions will be 38rad/hour at one metre from the core. The Americans used a Molten Salt Breeder Reactor and fast chemical separation of the nuclear waste however even this method was not quick enough because extra neutron bombardment leading to Thorium 231 or through neutron decay of U233 directly to U232 could not be eliminated. Cyclotrons avoid that issue. It should also be noted that a terrorist bomb built from U233 would shine like a beacon into space from Gamma emissions and make it detectable by satelite. It certainly could not be smuggled unless the U233 were exceptionally pure and well claded.

PS Just reread part of Sublette’s work. He lists the nominal critical mass of U-233 as being about 16kg, U-235 as 48kg, and P-239 as 10.5kg. Again, U-233 is much closer to P-239 in this regard than it is to U-235. When you mention one kg in association with U-233, I assume you mean that as little as one kg of highly enriched U-233 could theoretically be detonated using certain techniques. Sublette mentions the one kg figure in relation to plutonium in this passage:

“Using an advanced flying plate design it is possible to compress a 1 kg plutonium mass sufficiently to produce a yield in the 100 ton range. This design has an important implication on the type of fissile material that can be used. The high compression implies fast insertion times, while the low mass implies a low Pu-240 content. Taken together this means that a much higher Pu-240 content than normal weapon grade plutonium could be used in this type of design without affecting performance. In fact ordinary reactor grade plutonium would be as effective as weapon grade material for this use. Fusion boosting could produce yields exceeding 1 kt with this system.”

Keeping in mind the fact that the nominal critical mass of U-233 is slightly larger than that of P-239, my guess is that it would take a bit more than one kg of U-233 to go off, using any of the various exotic techniques developed since WWII to detonate sub-critical amounts of fissile material. That’s only a guess.

In any case, back to the German weapons R&D during WWII. In theory, a much smaller amount of U-233 would have been needed in order to fabricate a bomb than the amoung of U-235 or P-239 used by the Americans, provided the Germans had anything approaching the advanced engineering that would have been necessary. The Schumann-Trinks approach seems to lend credence to the idea that WWII German engineering was advanced enough in principle to achieve detonation of a sub-critical mass of bomb fuel. I am not as clear on the other method(s) explored by Diebner, Zippermeyer and Klemm. I had never before now heard of Operation Hexenkessel. Can you recommend some books and other sources where I can dig deeper into all this? Loved the bit about the KGB files I was aware that Karlsch had been sniffing around in Russian files. He is one of the very few Westerners who has ever managed that. Now that the climate in Russia has turned more nationalistic again, I doubt that such files are still available for examination by anyone other than Putin and his spooks.

Wow a lot to read Will and assimilate before i can answer properly. Regards Sublette mentioning 16kg you have to be aware that Sublette works off US experience with Uranium 233 bred in a breeder nuclear reactor using Thorium 232 mixed with Uranium 238. In such a reactor you can only load up to 7% Thorium before you smother the chain reaction therefore the chemically extracted Uranium 233 also had uranium 238 mixed with it.

That is why the critical mass in that case is 16kg see Kang & Von Hippel (U232 and the proliferation resistance of U233 in spent fuel)

In Russia one has to pay a Russian national as an archive researcher to find the information much like I personally can’t research US files because i am a British person living in New Zealand, however any American can access those US files via the Freedom of Information Act. I suspect one could still search KGB files if one did so appropriately. In both Russia and USA one also has to identify the document to them. Neither country will volunteer where to find something.

Another good book is “Two Against Hitler,” by Frank von Hippel.” He discloses for example that Erwin Respondek a German Reichstag Treasury official secretly leaked details of the Nazi Atomic project to Sam Woods in Switzerland until he was arrested by the Gestapo. He was freed from his death sentence when the SS took over the nuclear project and sent to parley with the Allies.

For example Respondek disclosed to the OSS the three underground tests in July 1943: Woods memorandum pp.18-19 Hull papers. Series of earthquakes in Schwabian alps 4th 14th and 22 July 1943 at 9 degrees east, 48.2 degrees North, close to Bisingen where German atomic scientists had relocated. (1943 intelligence reports of Woods in NA, RG 59)

It takes a great deal of scratching around to find these facts and recognise patterns in them.

Earlier you replied to me about a post by Timothy. I mentioned the Ju-390. If you found my website on the Ju-390 go back there and you will notice at the foot of the home page (I think) was my email address.

If you want to read the conversation about the Ju-390 wreck off Owl’s head then Google the following: (uboat.net owls head) and it should lead directly to a conversation by David M Brown who now lives at Burlington Vermont. He has a collector’s shop called the Gold Mine or similar. The person “plouise” who dived the plane wreck might be Patricia Louise Grey of California who owns a furniture business.

You mentioned elsewhere about Carter Hydrick’s theory that Uranium was used from the uboat U-234 for the Hiroshima bomb. I don’t subscribe to that theory, but it is interesting to read some of the information there. rteired Japanese Maj General Touransouke Kawashima disclosed on NHK TV in 1982 that only 2000kg of Uranium oxide ever reached Japan.

In October 1944 Japan received the plans for a Schumann Trinks weapon from Germany and immediately abandoned efforts to enrich uranium 235. Thousands of koreans were send into the mountains to prospect for Thorium (Monazite). At Konan (modern Hungnam) the japanese built a refinery to separate Thorium from the ore and on a hill nearby they built a powerful cyclotron for harvesting Protactinium 233. When the Soviets landed by parachute on 24 August 1944 they captured the facility intact and for several years after until a railway was built to Vladivostok they shipped out cases of uranium 233 by submarine. This is disclosed by the declassified letters of Maj General Shytkov to Stalin 1945-1948.

I have read a document called “German Technical Aid to Japan a Survey, dated June 15, 1945, , held by the Combined Arms Research Library at Fort Levenworth, ref# 3 1695 00561 5885. In that document at Chapter 14, page 177, it states Japanese POW learned in November 1944 from his Platoon commander (in the Philippines) that plans for the “German Atom bomb” were provided to Japan 1944. That the weapon worked on the principle of smashing atoms and the warhead was the size of a matchbox with a 1000 metre blast radius. The radio man from U-234 Wolfgang Hirschfeld also said before his death in 2003 that it was generally believed by the crew of U-2345 that Japan had already test blasted a nuclear weapon before they departed Germany. This tends to corroborate the MAGIC decrypt in the diplomatic signal from Stockholm. The Magic decrypt mentioned a 5kg warhead.

A sphere of Uranium 233 weighing 5kg has a radius of 3.87cm or about 6.2cm diameter which is about the size of a matchbox.

I have to correct my own post above since 6.2cm is the radii of a 16 kg sphere of U233 sorry for that. I am working off a public internet facility.I am tripping over my own data and confusing myself.

With Uranium 233 bred in a nuclear reactor which is the American method, the fertile Thorium to be transmuted is loaded into a Plutonium breeder reactor with Uranium 238 at a ratio of 7% Thorium. Anymore and the Thorium will smother the chain reaction by absorption. It is this 238U mixed with the Thorium which degrades the critical mass of 233U taken from the process. Thus the result is not 99.8% isotopically pure 233U but a much degraded admixture.

Critical mass is an obsolete concept if one uses fission boosting by Deuterium, or Tritium, or Lithium-6 Deuteride reactions to swamp the fissile target with an excess of neutrons.

Will I keep scanning for your messages. If you have my email just send me a fresh message as I would be happy to chat,

Simon, a couple more questions, if you don’t mind. Is it your belief that the 1945 German test detonation was the result of Project Hexenkessel, ie, a fuel-air bomb that was somehow boosted by the addition of some sort of fissile material to chemical explosives? This would have been on an entirely different track than the Schumann-Trinks design you have discussed in other places. A fuel-air bomb augmented by this sort of qusti-atomic approach would leave very little in the way of radioactive residue behind—which might explain both the apparent lack of radioactivity found by recent investigations at the test site, and also the fact that two eyewitnesses thought they were witnessing an atomic bomb blast. Perhaps what they were really seeing was a fuel-air bomb that might or might not have been made more powerful by the addition of fissile elements. If so, we would be talking about a very interesting approach to a massive detonation, and one that would also have been dramatically less expensive to produce—though how practical or deliverable or mass producible such a bomb would have been, I don’t know. It’s hard to say, as well, just how powerful the Hexenkessel – Zipprmayr bomb was in terms of its explosive yield. Certainly it would have been much stronger than any “conventional” chemical explosive of its day, but I can’t believe, at least at this point, that it would have approached the firepower of a true supercritical fission bomb.

Anyway, just thinking out loud here. By the way, I sent you an email after finding your email address on your site about the Ju-399 and hope you received the message. Thanks again for all of the excellent information you’ve shared here.

No, I don’t mind at all, it’s a subject which fascinates me…
Yes Hexenkessel (translated: Devil’s Cauldron) was an entirely different track from the hollow charge nuke tested at Ohrdruf which was tested twice in October 1944.

The Schumann Trinks weapon according to a witness had a fireball 100 yards across which I have seen this estimated as being equivalent to 0.814 kilotons. Germany was intending to use this warhead for the V-2 rocket, but were forced to abandon this plan.

The bi-conical implosion warhead developed by Schumann & Trinks is what we now call a third generation, boosted fission warhead. If you want to learn more about First, Second Third and Fourth Generation nuclear weapons, you should Google: “The Physical Principles of Thermonuclear Explosives, Inertial Confinement Fusion, and the quest for Fourth Generation Nuclear Weapons,” by Andre Gsponer and Jean-Pierre Hurni.

Carly Sublette also has an online description of how modern nuclear weapons work. The Nagasaki Mark III bomb technology was left behind in 1948.

The Hexenkessel bomb tested twice at Ohrdruf was a hybrid nuclear device based on an earlier Fuel Air Explosive (“FAE”) coal dust bomb, which was tested at Doberitz testing ground in August 1943. At Doberitz this weapon had a blast radius of 600yds (700m). It was the Luftwaffe initially which was most interested in using the coal dust bomb to disrupt formations of Allied bombers.

Zippermayer was very clear that his device began life as a Fuel Air Explosive(“FAE”). He was equally clear that the SS modified it with radioactive isotopes. There was no confusion in German descriptions between FAE and nuclear weapons. Some have tried to suggest that these large test explosions were simply confused with nuclear blasts, but that is untrue.

The original coal dust bomb was mentioned in Allied Intelligence reports by four separate Allied agents and was considered by the British war Cabinet in July 1943. It was cited by the Combined Intelligence Objectives Sub-committee (“CIOS”) report number XXXII-125. That report mentions “…but additionally there was a V-3 weapon a larger version of the V-1 with an incendiary warhead instead of the high explosive normally used,” which was thought to have a 3,500 mile range. This “Super -1” is also was referred to being developed by the Flodtmann plant at Breslau. I have read German commentators online refer to a Report entitled: “Atomic Target New York” dated 13th December 1944 which infuriatingly does not cite a file reference number, but does mention interrogation of a German POW about plans and drawings seen at the Flodtmann Plant. That report it is alleged also links Dr Ferdinand Trendleberg of Seimens Schukert Werke along with plasma physicist Max Steenbeck and nuclear physicist Barwell to a new atomic warhead for the Super V-1. That report allegedly mentions manufacture of a new hydrogen bomb warhead for the Super V-1 which occurred at an underground laboratory in Pulverhof at Rastow (Schwerin).

According to interviews with Zippermayer who did not understand nuclear physics involved a pinkish radioactive waxy agent was added to his coal dust warhead weapon in late 1944.

Rob Ardnt may have been the person whom I read some years ago online saying powdered Uranium was added. I have no idea beyond this of the original source for the claim that Uranium was added, just that I have seen claims by people who are generally well informed that Uranium powder was added to the coal dust bomb. Zippermayer noted the pinkish liquid had to be added shortly before use as it degraded quickly. Knowing that Prof Gerlach notes the SS wanted to develop Tritium for nuclear weapons in September 1944 and that this could be done quite easily by irradiating Lithium with X-rays, it leads me to assume that Tritium and Uranium oxide were added. It would make sense to also add Beryllium oxide since this emits neutrons when explosively compressed, or exposed to Alpha radiation and the Nazis were indeed refining Beryllium in the Degaussa refinery at Orienberg where Uranium was also being refined. I have no idea if the Uranium additive was enriched or not. It may have been in liquid solution with the Tritium.

Assuming these were the key additives I can only assume that the coal dust bomb provided the necessary compression for igniting a boosted fission explosion.
To learn more, why not Google, “Hitler’s Suppressed and Still-Secret Weapons, Science and Technology” by Henry Stevens which can be read online?

Stevens has researched three interviews given by SS Ober-Scharfuhrer Dr Ing Mario Zippermayer to US Army Intelligence at Salzburg after the war. Zippermayer was also a captain in the Luftwaffe and was working on developing a Fuel Air Explosive for the HS-117 guided Surface to Air Missile with the intention of breaking up bomber formations, when the SS approached him to develop his weapon for them.

One of the reports concerning Zippermayer is available at the Imperial War Museum, London:

CIOS Report, Item No.1,4,& 5, file No.32−109, page 22, Interrogation of Dr. Hans Friedrich Golg (aka Gotte), Jan 17, 1946, G−2 Division, SHAEF (Reer) APO.

Gotte, Klemm and Zippermayer were the three men responsible for adapting the coal dust bomb to a hybrid atomic weapon for the SS. TheOperation Hexenkessel weapon used “Tesla methodology” which implies plasma physics or the compression of Tritium to form an X-ray plasma.

Dr Arthur Klemm was apparently the real inventor of the Hexenkessel bomb and researchers need to focus on reports of his interrogations. That bomb was aerial dropped from an aircraft over a forest above Starnberger See, SW of Munich which is also report in BIOS final report 142G. This explosion it was noted had a blast radius of 4.5 kilometres and damage out to 12.5 km, putting it in the category of equivalent to the Hiroshima bomb.

Yes any boosted fission bomb typically has very complete combustion of the fissile mass (ie Uranium). That is because saturation from external neutrons ensures little is left uncombusted. Perhaps in the case of enriched U235 maybe all you could find is Cesium 137 and some U238 fall out present. The blasts at Ohrdruf were under the control of the SS and Operation Hexenkessel formally commenced on 8 March 1945 during the Ohrdruf test blasts. Hexenkessel was itself preceded by Operation Humus.

At Hiroshima by 1983, U235 was undetectable above normal environmental levels. Nuclear fall-out is almost entirely gone three months after a conventional blast. If radioactive fall-out was so undetectable at Hiroshima in the years after WW2 then it is no surprise how little evidence remains at Ohrdruf, or Rugen test sites, yet the existence of Cs137 at both sites is still notable. At Rugen two water filled craters on Bug Isthmus are contaminated by Cs137.

The German 2006 PTB report of the Ohrdruf site soil samples failed to analyse the ratio between Cs137 and Cs135. This ratio would chronologically date the event which caused the Cs137, but inexplicably the PTB never calculated this simple aspect.

To correct you my website is about the Ju-390 and I created others about the Nazi atomic bomb and the Nazi Bell.

Woops, yes, I meant “Ju-390”. Sorry for the incorrect model number!

Regarding Schumann-Trinks: is it your belief that at least a couple of these weapons—the equivalent in explosive yield to modern “battlefield nukes” or tactical nuclear weapons—may have been used against the Russians on the Eastern Front during WWII? If so, I can only assume that the only reasons more of them were not used were either 1) Germany couldn’t produce enough bomb fuel fast enough to build more than a handful of these weapons, and/or 2) that the Allies were able to produce credible threats of massive retaliation via poison gas and bioweapons such that the Germans were deterred—though they obviously kept working on other technology designed to snatch victory from the jaws of defeat via some kind of massive, last second bombs.

Of course we’re not talking only about the German effort, but also how it may have intersected with Japan’s nuclear weapons programs. There is a MAGIC intercept (which you cite elsewhere and which I have seen personally at the US National Archives) in which a Japanese Army attache based in Stockholm reports back to Tokyo that the Germans have used a “genshai hakai dan”—literally “element bomb”, or so some native Japanese speakers have informed me. In any case that Japanese term means “atomic bomb”. You state upthread that the Japanese were given plans for the Schumann-Trinks device. I had speculated in a recent conversation with another researcher that that might have been the case but had not seen you make that specific claim except in this thread. Do you have any specific documentation for this claim?

Loved the info about Cs-137 and how it relates to the German detonations. I have read an English translation of a report from a German technical institute regarding testing done at Ohrdurf in which it is claimed that no radioactive contamination consistent with a nuclear detonation was found—but I wondered about their methodology and thoroughness, to say nothing of the political climate in Europe, any of all of which might have resulted in less than reliable conclusions.

Unfortunately I am pressed for time here, Simon, but please allow me to again invite you to correspond personally. I have emailed you using the contact information from your Ju-390 website and would love to have a more in depth correspondence if you are willing. I understand if that doesn’t work for you and in any event I thank you for sharing all that you’ve shared here.

Sorry Will if I have missed your email invitation. I will hunt for it when i have a chance too. I am on a public internet facility here. I would be happy to correspond. Re send an email to me if you can, I must have missed it.

The PTB also covered up a leak of radiation from a german research reactor in 1986 and tried to pass the blame off on Chernobyl, when subsequent independent analysis showed the leukemia outbreak was actually caused by hi-tech beads of a compound consisting Plutonium, Americum and Curium, coated in Titanium, which had nothing to do with Chernobyl. I place no faith in the PTB to tell the truth.

A guy called Doug deitrich a former US DoD archivist from San Francisco came across German WW2 files mentioning the use of german nukes against the Soviets in Pomerania which deitrich says he was ordered to destroy.

Two German authors Meyer and Mehner published a letter from a Dr Lachner living in Argentina who recounted that wartime germany built 15 such nukes during the war two of which he claimed fell into Soviet hands and were subsequently tested by the soviets after the war. This might explain how the soviets quite quickly were able to shrink nukes into ballistic missiles as that is quite a jump from the Nagasaki Mark III bomb to Third generation nukes The Soviets published unclassified scientific papers on Third Generation techniques in 1946 six years before USA mastered that technology in the Swan device.

Back later when I get the chance but there was a USN report dated June 15, 1945, which cites this.

On 12 September 1986 a fire at the GKSS site radioactive material near Garching in Germany released synthetic radioactive beads which were blamed on Chernobyl. That is the reference I made in my last post. Later analysis proved it was nothing to do with Chernobyl after which the German authorities remained tight lipped and refused further comment. The synthetic radioactive beads were part of experiments with Fourth Generation nuclear weapons. That is to say weapons using extremely heavy synthetic elements beyond Plutonium or else weapons using anti-matter. The CERN complex collects anti-matter with the large Halidron collider for development in incredibly miniaturised lightweight neutron bombs with incredible yield potential compared with Plutonium. The irony is that European taxpayers funded CERN for peaceful nuclear research.

Back to the 1945 USN Intelligence report it is entitled: “German technical Aid to Japan, a Survey” June 15,1945, held by Combined Arms Research Library, Fort Leavenworth, KS file ref:- 3 1695 00561 5885. (paragraph 14, page 117) which details interrogation of a POW in the Philippines who disclosed Germany gave Japan technology for a Uranium atom splitting bomb in 1944.

A friend of mine who is writing about Japan’s nuclear facility in Konan tipped me off recently that there will soon be further revalations that the Allies were aware in 1944 of Atomic bomb technology contacts between Japan and Germany.

Soviet Maj General Shytkov wrote several letters to Stalin concerning a Thorium refinery at Konan and a cyclotron facility there for harvest of Uranium 233. The Soviets continued to operate the plant for some years after the war inside North Korea..The North koreans are practically swimming in the stuff.

As for Ohdruf the report concludes that it can not dertermine whether or not there was an atomic explosion at Ohrdruf which seems a rather inconclusive reply. It said that neither Uranium 235 nor Uranium 238 could be detected there, however harvesting U233 from Thorium in a cyclotron device would not involve either U235 or U238. Furthermore U235 was undetectable above background levels at Hiroshima by 1983, so it proves absolutely nothing in their report..

The saddest thing of this whole web page to me, is how it features an alleged wartime drawing of a Plutonium weapon (from 1941) which was obviously a fake and unfortunately Karlsch was discredited by his belief in it. In all other respects Karlsch was quite correct and should have paid more heed to the Schumann Trinks weapon.

The PTB report on soil analysis at Ohrdruf is deeply flawed because it refers to no attempt at fission track analysis to chronologically date the fall out there. If Caesium 137 found there was caused by a 1945 event then in undisturbed soil you would find it at a depth of 3 centimetres. Soviet era tests would leave a strata of 137Cs at 2cm and Chernobyl deposits would not be found any deeper than 0.5cm. The report is silent on any attempt to analyse this. Furthermore if there were 137Cs at 3cm deep then you would check the ratio of 137Cs with 137Ba, since Barium is the stable decay product. If the ratio at 3cm deep were 18% Caesium to Barium -137.

The PTB refuses to release the actual report and it’s raw data so is unavailable for independent review.

Hello again, Simon! Love the information you’re posting on here. FYI, I re-sent an email to your gmail account, the one in which you spell your name with a “y”. (I’m not posting it in this thread in case you’d rather keep it private.) Please let me know if you received it, and of course be sure to check your spam folder. In general, it appears to me that you are looking in some different—and also very productive—places for information about all this than where I have been digging. Broadly speaking, it would seem that most of your information comes from military and military intelligence sources where most of mine comes from government and “spook” sources, ie, OSS and MAGIC. Just to show you how popular culture can distort your perceptions if you’re not careful, I always gave the OSS – MAGIC end of the spectrum more credit because (I now realize) of the generally more “sexy” reputation the OSS, CIA and KGB enjoy in many corners of both fiction and history. However: you have definitely corrected my perception and have pointed me back to military intel as a very good place to look. You’ve also obviously had access to some Russian – Soviet sources I have longed to dig through their files, as well, but never had the resources or the connections to do so. I am glad you and Karlsch are among the very few in the West who have ever made any kind of detailed survey of those sources.

So, yes, I would welcome the opportunity to correspond and hope to do so in the near future.

Will I don’t have particularly good access to Soviet sources Will but what i have found is that it is invaluable to Google search ion foreign languages and in the case of Russia to use Google translate to cut n paste search terms in their cryllic alphabet and then trawl and translate the hits back from Russian. Countries behind the former Iron Curtain have developed different source material from the west.

No I can’t find or recognise your email in either of my usual email accounts. Do you refer to my symngun account?
This bewilders me. I am used to tons of spam so I don’t mind to publish the start of my address.
Please keep trying Will, likewise i’d enjoy the chat. I suspect you are William J P from the militaryphotos forum where I have begun posting again after a long pause.