 Evill was promoted to full lieutenant on 15 August 1914 and was appointed an acting flight lieutenant on 4 December 1914 on securing a transfer to the Royal Naval Air Service which by 1914 had gained its independence from the Royal Flying Corps.Evill spent much of the First World War on operational flying duties over the Western Front, flying out of Dunkirk from February 1915 onwards.Probably around the summer of 1915 he took up duties on No.