The Atlantic
Battle of the Atlantic
The Battle of the Atlantic was especially important for the Allies as convoys of resources coming from the United States were delivering essential resources to Britain. However, U-boat packs from Germany often made it incredibly difficult for these convoys and caused severe losses for Britain and her Allies (Battle of the Atlantic 2021).
“Convoy of 24 ships steaming south of Newfoundland on 28 July, 1942.”
“80-G-21187 North Atlantic Convoy, 1942.” Naval History and Heritage Command.
Bombe's Aid in the Atlantic
U.S. Navy Cryptanalytic Bombe - National Security Agency; YouTube
Before a fourth rotor was added to the Enigma, and when the Allies could read the transmissions, the Allies were able to use the decrypted information not only to divert convoys away from U-boat packs, but also to locate them, which allowed them to corner and sink a U-boat easily (Wilcox 2002, 22).
When the Allies were dealing with Germany's four rotor Enigma machines, the United States helped by modifying the Bombe so that it could counter the Enigma’s enhancements. This development allowed the Allies to once again read naval Enigma transmissions (World War 2: U.S. Navy Cryptanalytic Bombe 2021).