Major F.N.W. Henzell-Ascroft was originally commissioned into the Royal Engineers in October 1942, gaining promotion to Lieutenant in April 1943 and to Captain in November 1948. Latterly an Army Quantity Surveyor, he was a Licentiate of the Royal Institute of British Architects and a Professor Associate of the Surveyors' Institute. Henzell-Ascroft was promoted to Major in June 1953 and was serving on the Staff of Scottish Command in the following year.