Reconstructing the past: Codebreaking machine to be pressed back into service again

A codebreaking machine which helped decode top secret Nazi communications is to go back into service again.

The Turing-Welchman Bombe was an electro-mechanical device designed by Alan Turing and Gordon Welchman. It was based on a Polish concept, to automate the deciphering of Enigma-encrypted messages during the Second World War.

This week a reconstructed Bombe machine housed at the The National Museum of Computing on Bletchley Park will try to find the key of the day and break Enigma messages just as it did during the Second World War.

The whole attempt will be live streamed this Friday.

Ruth Bourne, a wartime Bombe operator, will be present to verify the process as the TNMOC Bombe Team attempt to find the key to decrypt messages that will be sent from Poland throughout the day.

The challenge is part of a live video link-up with the World Computer Congress in the Poznan Supercomputing Centre, Poland.

The Turing-Welchman Bombe was the electro-mechanical device designed by Alan Turing and Gordon Welchman, based on a Polish concept, to automate the deciphering of Enigma-encrypted messages during the Second World War.

In the early 1990s John Harper, a retired engineer, reconstructed a Bombe machine as a tribute to the wartime code-breakers at Bletchley Park. The reconstructed Bombe was completed and officially launched in 2007.

The reconstruction replicates the standard British Bombe that contained 36 Enigma equivalents, each with three drums wired to produce the same enciphering effect as the Enigma cipher machine motors.

The reconstructed Bombe was moved to The National Museum of Computing at the end of April 2018.

Watch our report about the campaign to move the Turing-Welchman Bombe below.

You'll be able to watch the live stream of the challenge here from 8:30am on Friday.