In this episode from the Stuff You Should Know podcast, the hosts explore Operation Gunnerside, a daring WWII sabotage mission. As the Allies feared Nazi Germany was pursuing an atomic bomb, they targeted the Vermork plant—the world's only major producer of heavy water. This rare substance, crucial for nuclear reactions and plutonium production, prompted Allied efforts to disrupt the German supply through covert operations like Gunnerside.
The hosts recount how Norwegian resistance fighters, trained by scientist Leif Transtad, infiltrated Vermork to plant explosives and sabotage heavy water production. Though Nazi Germany restored Vermork months later, such bold operations and subsequent disruptions stalled their atomic program. The precise impact remains debated, yet Gunnerside stands as an iconic WWII story showcasing the Allies' determination to thwart Germany's nuclear ambitions.
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The discovery of nuclear fission by German physicists, Sanger-Katz explains, escalated fears among the Allies that the Nazis were pursuing an atomic bomb. This spurred efforts to sabotage the German nuclear program.
Heavy water's ability to slow down neutrons made it vital for controlled nuclear reactions and plutonium production, Sanger-Katz notes. While the U.S. used graphite, Germany strategically chose rare heavy water as a moderator, with the Vermork plant in Norway as the world's only major producer.
Rather than risk civilian casualties by bombing Vermork, the Allies opted for covert sabotage operations like Operation Gunnerside, Sanger-Katz recounts. Recruited and trained by scientist Leif Transtad, Norwegian resistance fighters infiltrated Vermork, planting explosives to disrupt heavy water production before escaping undetected.
The Nazis restored Vermork's heavy water production months after Gunnerside, but further Allied sabotage like sinking a ferry transporting heavy water continued disrupting the supply, Sanger-Katz explains. However, the precise delay to the German atomic program from these efforts remains debated, though the Gunnerside operation has become an iconic WWII story.
1-Page Summary
As World War II escalated, the role of heavy water in nuclear research became a pivotal factor in the atomic weapons race. German physicists discovered nuclear fission, prompting fears among the Allies that the Nazis were pursuing an atomic bomb. This fear led to a covert effort to disrupt the German nuclear program.
The discovery of nuclear fission by German physicists intensified the global weapons race, with the hypothesis that nuclear fission could create a large explosive reaction. The Allies, worried that the Nazis were actively working towards an atomic bomb, initiated a series of espionage and sabotage efforts to hinder their progress.
Heavy water (D2O), distinguished from regular water by an extra neutron, is vital in nuclear reactions due to its capability to act as a moderator. This ability to slow down neutrons makes it a crucial element in the controlled reaction necessary for plutonium production without causing an uncontrolled explosion. While the United States relied on readily available graphite as a moderator, Germany's choice to use heavy water was a strategic error due to its rarity.
The Vermork power plant in Norway, the world's leader in heavy water production, became a strategic point of interest for both the Axis and the Allies. Heavy water is inherently scarce, occurring in only about one molecule per 20 million molecules of regular water, which made the Vermork plant, the only place in the world producing it, a criti ...
Heavy Water's Strategic Role in German Nuclear Program and Allied Countermeasures
Norwegian Scientist Leif Transtad was critical in the development of the operation against the German heavy water plant. Transtad, who had fled to the UK, possessed specialized knowledge due to his background as a chemist involved in producing heavy water. He collaborated with British intelligence to train commando units in sabotage techniques. In Scotland, these units prepared for the mission's challenging conditions, anticipating the forbidding terrain of the facility's remote location.
Operation Gunnerside was a tactically nuanced mission under the leadership of Joaquin Rundenberg, following the failed Operation Freshman. The difficult approach involved navigating either a minefield, a Nazi-guarded suspension bridge, or a gorge with a treacherous river. The saboteurs chose the gorge, an unguarded route because of its perilous nature. Armed with heavy-duty bolt cutters and quiet resolve, the team of nine from the Norwegian resistance, Kompany Ligna, breached the first line of defense, a fence that they cut through expediently, avoiding noisy disruptions.
Upon reaching the Vermork plant, Rundberg and his crew had to adapt when a cooperative inside man failed to attend work, likely due to illness or a hangover. Utilizing a backup entry point, a cable shaft, Rundberg and a teammate, Kaiser, infiltrated the facility. They faced challenges such as taking and eventually chloroforming a compliant watchman to avoid detection. With two teams working simultaneously, explosives ...
Gunnerside Sabotage Operation Against German Heavy Water Plant
The Gunnerside Operation was a crucial effort by Allied forces during World War II to disrupt the German atomic program. However, the operation's long-term impact and its significance in delaying the Nazi pursuit of an atomic bomb have been topics of ongoing debate.
After seizing the Vermork plant, the Nazis increased heavy water production crucial for their atomic bomb aspirations. The Gunnerside operation successfully stalled this production. However, the Germans were able to resume operations a few months later, in May of the same year, indicating that while Gunnerside did disrupt the Nazi atomic program, it was not a permanent setback.
The Allied forces' sabotage campaign continued with the bombing of the Vermork plant by the Americans. Unfortunately, this operation caused the death of 22 Norwegian civilians, and due to the plant's underground location, it suffered no significant damage. The Nazis responded by moving their heavy water operations to Germany. The Allied forces did not relent and, in February 1944, executed another sabotage operation against German heavy water transport by targeting the ferry Hydro. The operation was successful but resulted in the tragic loss of 18 lives, 14 of whom were Norwegian civilians.
The debate surrounding the Allied efforts, including the Gunnerside operation and the sinking of the Hydro ferry, centers on their effectiveness in delaying the German nuclear program. There's uncertainty regarding how significantly these operations impacted the program and how close the Germans were to successfully building an atomic bomb.
Impact of Gunnerside Operation on German Atomic Program
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