 Continuing his work on electronic instrumentation he contributed to the development of nuclear physics at Imperial under G. P. Thomson.On the eve of the Second World War, Wynn-Williams, like many of his scientific contemporaries, was recruited to work on the developing discipline of radio detection and ranging (RADAR) at the Telecommunications Research Establishment, later the Royal Radar Establishment, Malvern.On 1 February 1942, the Allied success in breaking Nazi German naval Enigma messages suffered a serious setback.