Tommy Flowers

Thomas Harold Flowers
OBE
Thomas Harold Flowers; OBE
	Tommy Flowers - possibly taken around the time he was at Bletchley Park
Born	22 December 1905; Poplar, London, England
Died	28 October 1998 (aged 92); Mill Hill, London, England
Nationality	British
Occupation	Engineer
Spouse	Eileen Margeret Green
Children	2

A modern reconstruction of Colossus at Bletchley Park

Thomas Harold Flowers, BSc, DSc,^[1] OBE (22 December 1905 – 28 October 1998) was a British engineer. During World War II, Flowers designed Colossus, the world's first programmable electronic computer, to help solve encrypted German messages.

The first Mark 1, with 1500 vacuum tube valves, ran at Dollis Hill in November 1943, and then at Bletchley Park in January 1944.

A Mark 2 redesign with 2,400 valves had begun before the first computer was finished. The first Mark 2 Colossus went into service at Bletchley Park on 1 June 1944, and immediately produced vital information for the imminent D-Day landing.

Results

Flowers had a crucial meeting with Dwight D. Eisenhower and his staff on 5 June. A courier handed Eisenhower a note summarizing a Colossus decrypt. This confirmed that Hitler wanted no additional troops moved to Normandy, as he was still convinced that the preparations for the Normandy invasion were a diversionary feint. Eisenhower announced to his staff, "We go tomorrow".^[2]

Earlier, a report from Field Marshall Rommel on the western defences was decoded by Colossus and showed that one of the drop sites for a US parachute division was the base of a German tank division. The site was changed.^[3]

Years later, Flowers described the design and construction of these computers.^[4]

References

↑ Lee, John A. N. (1995). International Biographical Dictionary of Computer Pioneers. Taylor & Francis. p. 306. ISBN 9781884964473.
↑ Flowers, Thomas H. 2006. D-Day at Bletchley Park, in Copeland B.J. (ed) Colossus: the secrets of Bletchley Park's codebreaking computers. Oxford: Oxford University Press, pp. 78–83. ISBN 978-0-19-284055-4
↑ "'Station X'". Archived from the original on 2014-02-22. Retrieved 2013-11-02.
↑ Howard, Campaigne (1983). "The design of Colossus: Thomas H. Flowers". Annals of the History of Computing. 5 (3): 239. Retrieved 2007-10-12.

[1] Lee, John A. N. (1995). International Biographical Dictionary of Computer Pioneers. Taylor & Francis. p. 306. ISBN 9781884964473.

[2] Flowers, Thomas H. 2006. D-Day at Bletchley Park, in Copeland B.J. (ed) Colossus: the secrets of Bletchley Park's codebreaking computers. Oxford: Oxford University Press, pp. 78–83. ISBN 978-0-19-284055-4

[3] "'Station X'". Archived from the original on 2014-02-22. Retrieved 2013-11-02.

[4] Howard, Campaigne (1983). "The design of Colossus: Thomas H. Flowers". Annals of the History of Computing. 5 (3): 239. Retrieved 2007-10-12.

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