How Hitler's atom bomb plans sank with a tiny ferry
He was a boat ride away from building a bomb to blow up London, but the fretting Allies decided they had to act
Hitler was just a ferry ride away from getting hold of a crucial ingredient for an atomic weapon to blow up London, a new documentary reveals.
In the middle of a Norwegian lake, 160km from Oslo, naval historians and scientists have located the boat on which the Nazis were transporting barrels of heavy water for use in German nuclear reactors. The SF Hydro transporter ferry was sunk on British prime minister Winston Churchill’s orders in 1944, but until now nobody knew whether the craft really contained heavy water.
For the new National Geographic series Drain the Oceans, scientists mapped the lake bed and raised the ferry virtually to find out what was on board. They discovered at least 18 barrels which tests showed contained heavy water. Many more are thought to be crushed beneath the sunken boat.Professor Eric Grove, a naval historian, said: “After the war, those involved in the German nuclear programme said that the loss of the heavy water was absolutely decisive. It stopped their reactor programme in its tracks.”
By 1934 the Norwegians had built the first commercial plant to produce heavy water, which was perched on a precipice above Lake Tinn at Vemork. Germany began its Uranverein (“uranium club”) project in April 1939, months after scientists Otto Hahn and Fritz Strassmann discovered nuclear fission, giving them a significant head start over the US Manhattan Project.
Heavy water – so called because each hydrogen atom contains a neutron as well as a proton in its nucleus – was critical to slowing and controlling the fission process.When the Nazis invaded Norway in 1940, they took control of the Vemork plant. The Allies were so fearful that Hitler would use heavy water to build nuclear weapons that London ordered a series of sabotage missions, culminating in Operation Gunnerside in 1943, in which Norwegian commandos blew up the plant.
The raid and the Hydro’s sinking were portrayed in the film The Heroes of Telemark, starring Kirk Douglas.
After the raids the Nazis realised they needed to safeguard their remaining stockpile and, on February 20 1944, began moving a year’s output of heavy water by train and ferry from Vemork to the reactor site in Germany. However, on Churchill’s orders, Norwegian resistance fighters attached a bomb to the ferry timed to explode when it reached the centre of the lake.Dr Fredrik Søreide, of the Norwegian University of Science and Technology, said: “We wanted to go down and take up a barrel to prove that this was in fact the heavy water that was being shipped to Germany.”
The new scans revealed the 56m ferry still in one piece. Tests proved that not only was there heavy water in the barrels, but enough to put Germany well on the way to becoming a nuclear power.
–© The Daily Telegraph