Beating Nazi Germany's Enigma Code Won The Allies World War II

November 15, 2019 Topic: History Region: Europe Blog Brand: The Buzz Tags: IntelligenceWorld War IIEnigmaNazi GermanyAllies

Beating Nazi Germany's Enigma Code Won The Allies World War II

Cooperation between America and Britain was crucial.

The 1,000 civilians, WAVES, and servicemen working in Building 26 immediately began turning out production Bombes, which they nicknamed “Grey Elephants.” Each one measured seven feet tall, 10 feet long, and two feet deep, while weighing approximately 5,000 pounds. A total of 121 Bombes were eventually manufactured with most of them being shipped to the Naval Communications Annex in Washington, D.C. The first Bombe arrived there on September 12, 1943.

Some 285 of the WAVES who had helped build these powerful new decryption machines accompanied their Grey Elephants to the Naval Communications Annex as Bombe operators. The glamour of duty in exciting Washington, D.C., was counterbalanced by long hours spent inside a swelteringly hot, noisy work environment. Crowded living conditions, rotating shifts, and unceasing pressure to keep silent about what they were doing took a toll on these young women. Many WAVES carried their secrets to the grave.

Meanwhile, the wizards of Bletchley Park continued to make great strides against Germany’s new U-boat ciphers. They scored an enormous victory on October 30, 1942, when a boarding party off the destroyer HMS Petard managed to “pinch” several codebooks from badly damaged U-559 near Port Said, Egypt. This intelligence coup came at high cost, though. Two brave British sailors drowned when the doomed submarine unexpectedly sank with them still inside.

A British Bombe that could read four-rotor Enigma ciphers also entered service in late 1943. By then, however, Admiral Dönitz’s last great U-boat offensive had ended in utter defeat. Other technological marvels such as microwave radar, aerial homing torpedoes, and radio direction-finding receivers enabled Allied forces to deliver unrelenting attacks on Nazi Germany’s submarine fleet. The great armada that invaded Normandy on June 6, 1944, crossed the English Channel largely without fear of underwater attack—only a few Unterseeboote remained at sea by this point in the war.

There was still plenty of work for the U.S. Navy Bombes and the WAVES who ran them. Joe Desch’s design included a feature that allowed his machines to decipher three-rotor Enigma traffic, volumes of which were intercepted daily from the German Army and air force. GC&CS, now a fully British-American operation, asked OP-20-G to help reduce the backlog. Washington-based Bombe operators devoted approximately 45 percent of their processing time to decrypting these tactical messages; the rest of their efforts went toward fighting the U-boats.

Recently declassified reports credit the U.S. Bombes with breaking a total of 301,629 enemy messages. It may never be known how many of these jackpots resulted in actionable information. However, Ultra did figure in several American antisubmarine successes, including the spectacular capture of U-505 by sailors of Captain Dan Gallery’s Task Group 22.3 on June 4, 1944.

At war’s end, the feelings of suspicion and distrust that once existed among intelligence professionals from the United Kingdom and United States had been replaced by a spirit of genuine cooperation at all levels. Nowhere was this better illustrated than in the partnership that grew between GC&CS and OP-20-G. General Dwight D. Eisenhower, a man who understood much about the nature of coalition warfare, later remarked that the Allies’ ability to read Germany’s ciphers “saved thousands of British and American lives and, in no small way, contributed to the speed with which the enemy was routed and eventually forced to surrender.”

The international team of theoreticians, electrical engineers, and Navy WAVES who together defeated Enigma would wholeheartedly agree with Ike’s assessment.

A retired U.S. Army officer, Patrick J. Chaisson writes on a variety of World War II topics from his home in Scotia, New York.

This article was first published at the Warfare History Network.

Image: Wikipedia.