Born in India and educated in London, Lawrence Percival Coombes joined the Royal Naval Air Service in July 1917. Assigned to 12 Naval Squadron in January 1918, he was posted to 10 Naval Squadron two weeks later. After downing 15 enemy aircraft as a Sopwith Camel pilot, he returned to England in August 1918 and served the remainder of the war as an instructor with 204 Training Squadron in Eastchurch. Discharged from the Royal Air Force in March 1919, Coombes and two friends spent the summer barnstorming throughout Lancashire in surplus B.E.2e's. After obtaining a degree in engineering from London University, Coombes was employed by the Royal Aircraft Establishment and later served as technical advisor to the 1927 Schnieder Trophy Team. He emigrated to Australia in 1938 when he was selected to establish the Aero Research Laboratory in Melbourne. In 1960, while serving as a United Nations advisor, Coombes helped India establish its first aeronautical research laboratories.
Coombes personal records were deposited with the La Trobe Library, State Library of Victoria, in 1993.