Thomas (Tommy) Harold Flowers MBE (22 December 1905–28 October 1998) was a British General Post Office (GPO) engineer who, during World War II designed Colossus — an early computer — to assist the codebreaking efforts at Bletchley Park. Colossus, the world's first digital, (partially) programmable and electronic computer, was used to help crack messages encrypted using the German's Lorenz SZ 40/42 machine.

Flowers was born in London and, after an apprenticeship in mechanical engineering, he earned a degree in Electrical engineering at the University of London before joining the telecommunications branch of the GPO in 1926, moving to work at their research station at Dollis Hill in 1930.

During the War Flowers was asked to join the codebreaking efforts at Bletchley Park, and it was he who proposed solving the problems of the Heath Robinson machine by using an electronic system using valves. Despite the rejection of the idea initially because valves were seen as too unreliable, and subsequently because it was expected that the war would be over before the idea could be implemented, he went ahead without authorisation, even part funding the development himself. He was also noteworthy for cranking up the speed of the first Colossus machine to nearly double "to see how fast it would go".

Flowers received recognition after the war in the shape of a £1,000 lump sum, and the award of an MBE.

After the war, Flowers returned to the GPO but, unable to tell them of his wartime achievements, was unsuccessful in his attempts to get the organisation to develop the electronic telephone exchange.

See also

• List of electrical engineers

External links

• http://c2.com/cgi/wiki?TommyFlowers