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