On June 4, 1944, Task Group 22.3 (A), commanded by Captain Daniel V. Gallery, USN, captured German (Type IXC) U-boat, U-505. The capture took place about 150 miles west of the coast of Rio De Oro, Africa.
The cipher materials captured included the special “coordinate” code, the regular and officer Enigma settings for June 1944, the current short weather codebook, the short signal codebook, and bigram tables due to come into effect in July and August. The material arrived at the decryption establishment at Bletchley Park on June 20, 1944, and the Allies were able to break most of the Enigma settings by intense cryptanalysis, including heavy use of the electromechanical “bombes”. It saved work and time to have the Enigma settings for the U-boats which could be applied to other keys. The settings break was only valid until the end of June and therefore had an extremely limited influence on the eventual cracking of the Enigma code, but having the weather and short signal codebooks and bigram tables made the work easier.
Lieutenant Junior Grade Albert L. David, USN, posthumously received the Medal of Honor for his actions boarding the U-boat. U-505 had been patrolling the Gold Coast and was now homeward bound when she was caught. Under fire by depth charges from Chatelain and two Grumann F4F “Wildcat” aircraft, the submarine surfaced and immediately came under attack prompting the submarine to surrender. This capture marked the first time a U.S. Navy vessel captured an enemy vessel since the War of 1812.
Upon Germany’s surrender on May 7, 1945, the U.S. Navy no longer needed to keep U-505 a secret. The U-boat went on tour as part of the Seventh War Loan Drive to raise funds for the war against Japan. U-505 stopped at several East Coast cities, where spectators could climb onboard in exchange for purchasing war bonds.
In September 1954, U-505 was dedicated as a war memorial and became a permanent exhibit at the Museum of Science and Industry, Chicago, Illinois. In 1989, the U-boat was also designated as a National Historic Landmark. U-505 is the only Type IX-C U-boat in existence today. In 2019, the submarine was refurbished, restoring it to be closer to its original condition. Also, a special exhibit with many additional artifacts from the sub was opened in the general admission section of the museum.
The U-505 is one of six U-boats captured by Allied forces during World War II, and was the first warship to be captured by U.S. forces on the high seas since the War of 1812. In 1954, U-505 was donated to the Museum of Science and Industry in Chicago, Illinois and is now a museum ship.
(A) The Task Group consisted of USS Guadalcanal (CVE 60), USS Pillsbury (DE 133), USS Pope (D -134), USS Flaherty (DE 135), USS Chatelain (DE 149), and USS Jenks (DE 665).
Source: history.navy.mil
Station HYPO 
4 June 2020 at 10:10
Great story.
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4 June 2020 at 12:08
When I was a kid I lived in the Chicago area. I remember when they brought the U505 to the museum. It wasn’t until the 1990”s that I got to tour it at the museum. I was amazed at how tight the quarters were . I was station on the USS Intrepid in 1972. There is no comparison. Incredible story about the capture. From what I read the Germans tried to scuttle the U boat, it also was booby trapped. Someone from the US crew was able to prevent it from sinking and disarm the booby traps.
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7 June 2020 at 04:08
Very interesting! Thanks very much for posting. We’ve all probably seen the film, U-571. I’ve long suspected that movie took that name because, to Americans at least (and probably other nations as well), 571 was the hull number of the world’s first nuclear ship, USS Nautilus.
Naming a movie U-571 was probably a product of the folks in the marketing department. “571” has a far more familiar ring to it than “505” would—at least to Americans!
Thanks again for all your posts, Mario!
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