ðə dɪzˈaɪn, wˌɪtʃ wʌz ˌʌndɚtˈeɪkən baɪ wˈɪljəm sˈɪmpsən jˈuːzɪŋ ɐ nˈuːklɪəs lˈeɪaʊt wˌɪtʃ wʌz kˈeɪpəbəl ʌv ɛkspˈænʃən, wʌz ɐnˈaʊnst ɪn dᵻsˈɛmbɚ nˈaɪntiːnhˈʌndɹɪd sˈɛvənti sˈɪks ænd plˈænɪŋ pɚmˈɪʃən ɡɹˈæntᵻd ɪn mˈɑːɹtʃ nˈaɪntiːnhˈʌndɹɪd sˈɛvənti ˈeɪt.
The design, which was undertaken by William Simpson using a nucleus layout which was capable of expansion, was announced in December 1976 and planning permission granted in March 1978.