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U-571 is a powerful film that follows a US Navy submarine crew on a secret WWII mission to capture a German Enigma code machine from a disabled German U-boat.
Matthew McConaughey and Harvey Keitel lead the Battle-of-the-Atlantic thriller in a gripping chase between destroyer and submarine based on a true story - except, the movie is fiction. Director Jonathan Mostow reinvented history and enraged some Britons along the way.
The US Navy did capture the German submarine U-505 and two Enigma machines on June 4, 1944, though. So what’s the fuss all about? SPYSCAPE took a deep dive into the drama behind the scenes.
U-505: The Hunter Becomes the Hunted
In the final years of WWII, the US Navy created military formations to hunt German U-boats. Hunter-Killer Task Group 22.3, for example, consisted of a small aircraft carrier escort named the USS Guadalcanal (CVE-60) and five light destroyer escorts.
Guadalcanal was commanded by Captain Daniel V. Gallery - a former Olympic wrestler who flew Spitfires during the Battle of Britain. Gallery accessed the Top-Secret 10th Fleet, the US Navy's anti-submarine intelligence command in D.C. Inside the U-boat tracking room, codenamed F-21, Gallery learned the classified details of German U-boats, enhancing the mission's intelligence power. Gallery knew that a successful capture hinged on the Germans believing the sub was sunk, however. His team would need to maintain absolute secrecy about the capture.
The pivotal moment came on June 4, 1944, as Germany’s U-505 sub cruised off West Africa on the prowl for American and Allied ships. U-505 was a familiar and fearful name but on this day, the dynamics shifted. The German predator found itself in the surprising role of the prey. Under fire by depth charges from destroyer escort Chatelain and two F4F ‘Wildcat’ aircraft, U-505 surfaced and surrendered.
It was a historic capture. It had been more than a century since any US naval force boarded and captured an enemy vessel at sea. The German crew of 58 were captured, eventually transferred to a PoW camp in Louisiana, and segregated.
U-505 and the Enigma
The Germans assumed submarine U-505 was sunk and made no major changes in naval Enigma. The Enigma was a type of encryption machine used by the Germans to encode WWII military communications. It had rotating wheels and plugboard connections, creating complex codes for each letter.
The Dutch developed the machine to communicate banking secrets and the Germans bought the patent in 1923 for intelligence. Poland then bought an Enigma at a trade fair and procured a codebook from a French agent. The Enigma’s settings offered 150,000,000,000,000,000,000 possible solutions, but the Allies, especially at Bletchley Park in the UK, had successfully deciphered these codes, helping to turn the tide of the war.
The Intelligence haul from the U-505 sub matched - and perhaps even exceeded - the intelligence haul from the previous captures of submarines U-110 and U-559, Clay Blair writes in Hitler's U-Boat War.