A draughtsman living in Port Robinson, Ontario when he enlisted in the Royal Naval Air Service, William John MacKenzie served with the Dunkirk Seaplane Defence (later 213 Squadron), bombing and providing ground support for the advance of the Belgian army. Posted to 209 Squadron on 14 March 1918, he was wounded in action during the famous battle on 21 April 1918 that ultimately ended with the death of Manfred von Richthofen. He rejoined 213 Squadron on 8 October 1918 and remained with this unit until he left the Royal Air Force on 20 May 1919. In 1918 he scored 8 victories flying the Sopwith Camel. He was living in New York City in 1942, employed by the Federal Marks Agency.