Outstations from the Park

The first attempts at codebreaking were by analysing the intercepted messages after transfer to punched lettered sheets. The task was time consuming & rarely succeeded.

Alan Turing developed a basic Polish idea with Gordon Welchman and, through co-operation with Harold Keen of the British Tabulating Machine Company, an electro-mechanical machine was developed. This machine became known as the 'Turing Bombe'. The first prototype appeared in early1940 and the first British high speed bombe was produced in the first part of1943.

The complexity of the Enigma codes soon required large numbers of 'Bombe machines'. These were situated at Bletchley and other locations, known as 'Outstations'.

Wavendon, Adstock, Gayhurst, Eastcote & Stanmore together operated over 200 machines by the end of World War II.

The 'Bombes' were operated on an inter-service basis. Installation and maintenance, completed mainly by RAF and Civilian personnel, enabled an increasingly large number of Wrens to operate three eight-hour watches per day.

At its height there were over 1600 Wrens involved.

A US Navy Bombe machine, Photo courtesy of Jerry Proc
An American Naval Bombe Machine. Photograph courtesy of Jerry Proc.
Part of the Bombe reconstructed for the film 'Enigma'
A mock-up of a Bombe machine at Bletchley Park. Made for the Film 'Enigma'.
The former British Tabulating Machine Company building in Igneild Way Letchworth where the Bombes were assembled
The Icknield Way factory in Letchworth where the British Tabulating Machine Company assembled the 'Bombes'
Life in the Outstations

Security requirements meant that the machine blocks had only tiny windows at ceiling level and they were often situated behind high walls in order to deaden the noise and to provide bomb-blast protection. This meant there was very little natural light and coupled with the heat generated by the machines, working conditions were far from ideal.

For those Wrens based in the grounds of the country houses at Wavendon and Gayhurst, in the early part of the war, the seemingly idyllic rural surroundings need to be contrasted with the cold living quarters and lack of transport. There seems to have been less obvious security at these establishments - probably so as not to draw attention to the activities.

Locations of the Bombe machine outstations near to Bletchley Park
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