three shifts per day by some 600 WAVES (Women Accepted for Volunteer Emergency Service), 100 Navy officers and enlisted men, and a large civilian workforce. Approximately 3,000 workers operated the bombes to produce "Ultra" decryptions of German Enigma traffic. According to a contemporary US Navy report (dated April 1944), the bombes were used on naval jobs until all daily keys had been run; then the machines were used for non-naval tasks. During the previous six months, about 45% of the bombe time had been devoted to non-naval problems carried out at the request of the British. British production and reliability problems with their own high-speed bombes had then recently led to construction of 50 additional Navy units for Army and Air Force keys. The documentary, ″Dayton Codebreakers″, producer Aileen LeBlanc, was released in 2006 on American Public Television. Building The location in Dayton, Building 26 on the former National Cash Register Company, was an Art Deco design of Dayton firm Schenck & Williams and was located at Patterson Blvd and Stewart Street. The building was demolished by the University of Dayton in January 2008. See also Cryptanalysis of the Enigma Bomba (cryptography) Bombe Bletchley Park Ultra Bibliography History of the Bombe Project (US Navy memo, April 1944) John A. N. Lee, Colin Burke, and Deborah Anderson, "The US Bombes, NCR, Joseph Desch, and 600 WAVES: The First Reunion of the US Naval Computing Machine Laboratory", IEEE Annals of the History of Computing, Volume 22, No. 3 July – September 2000. Dayton Codebreakers IEEE Global History Network IEEE History Center Oral history interview with Robert E. Mumma, Charles Babbage Institute, University of Minnesota. Mumma recounts how NCR's war-time work on cryptanalytic equipment took all the company's effort, and how this shaped company policy resisting government contract work after the war. Oral history interview with Carl Rench, Charles Babbage Institute, University of Minnesota. References History of cryptography Locations in the history of espionage Signals intelligence of World War II NCR Corporation History of Dayton, Ohio