[3] In 1895, Henderson married Henrietta Caroline Dundas, who was appointed as a Dame Commander of the Order of the British Empire (DBE) in 1919.

[5] Following officer training at the Royal Military College Sandhurst, Henderson was commissioned into the British Army on 25 August 1883, joining the Argyll and Sutherland Highlanders as a lieutenant.

In February 1901, the commander-in-chief in South Africa, Lord Kitchener, appointed Henderson his director of military intelligence, a post he held until the end of the war in June 1902.

[16] A new Department of Military Aeronautics was established and Henderson was appointed the first director[1] and, with the outbreak of the First World War, he took up command of the Royal Flying Corps in the Field.

The decision to post Henderson and replace him with Sykes was not to Field Marshal Lord Kitchener's liking, and he ordered a reversal of the appointments.

[20][21] In 1915 Henderson returned to London to resume his London-based duties as director-general of military aeronautics,[8] which Sefton Brancker had been performing in his absence.

[23] He sat on the government's "Advisory Committee for Aeronautics", located at the National Physical Laboratory, under the chairmanship of Richard Glazebrook and presidency of John Strutt, Lord Rayleigh.

After the armistice, Henderson served as a military counsellor during the Paris Peace Conference[26] until the signing of the Versailles Treaty in June 1919.

[27] David Henderson Avenue, built on the former Joint Services School of Intelligence site in Ashford, Kent, is named after him.