A Father’s Day Trip
to Bletchley Park.
Our job is to decode the complexity of cloud and communication services for schools and businesses. So we got thinking: what do we use to decode things every day? Our brains. A lock and key. A computer…
The answer came on a Father’s Day trip to Bletchley Park. Between rounds of Tetris and Space Invaders in the computer museum (who could resist?), we found ourselves in the story of the Bombe: the machine that helped crack the German Enigma code.
The Bombe Project started in 1940 with just three people. Alan Turing, a Cambridge mathematician, came up with the original idea: a machine that could work out Enigma’s settings far faster than anyone could by hand.
The first Bombe, optimistically named ‘Victory’, started work on 14 March 1940 in half of Hut 1. The other half was the sick bay. Hmm… sterile. The whole unit was squeezed into a room 15 feet by 12 feet, which sometimes doubled as the dining room and sleeping quarters.
In March 1941 the Bombes moved into Hut 11, the first brick building at Bletchley Park. As more machines arrived, new stations opened nearby at Adstock and Wavendon. By the end of 1941 there were 16 Bombes at work, six of them in Hut 11.
A Daily Race Against the Clock
Every day the codebreakers had to find a brand new key: the wheel order, the wheel settings and the plugboard. The Army and Air Force picked three wheels from a set of five. The Navy chose from eight.
Enigma had one flaw: a letter could never be enciphered as itself. The codebreakers used ‘cribs’, words they expected to find in a message, and the Bombe raced through the settings looking for ones that fitted, ruling out the rest.