Correspondence on John Colville [former Private Secretary to WSC] being found unfit for a pilot's commission; includes letters between John Martin [Private Secretary to WSC], WSC, Sir Archibald Sinclair [Secretary of State for Air, later 1st Lord Thurso] and Ronald Melville [Private Secretary to Sinclair] on the inconvenience to WSC of releasing Colville, his progress in training, and the limitations of training in South Africa.