Son of Colin and Vera Clark, of Johannesburg, Transvaal, South Africa; nephew of Ina Dowson, of Geldeston. "One of the few" Battle of Britain pilot. Joined the RAF on a short service commission in April 1939. He joined 266 Squadron in October 1939 and was with the Fighter Interception Unit by 25th June 1940. On 13th October Clark was flying Blenheim L6805, operating as a target aircraft for an AI-equipped Boston. Due to an error in the use of the fuel cocks, he experienced engine failure and made a crash-landing near Lancing College. The aircraft was written off but he was unhurt. As a Flight Lieutenant with 137 Squadron, newly-formed and equipped with Whirlwinds, the squadron had flown its first operational sortie on 24th October, attacking the railway sidings at Landernean near Brest. On war memorial for King Edward VII School, Johannesburg.