Plane / Planes / Aircraft / Aeroplane / Airplane appreciation

So AIUI up until the end of the First World War Felixstowe was both an experimental station specialising in flying boat R&D and an operational station that operated seaplanes for anti-submarine duties over the Channel and the North Sea. The experimental station designed a series of Flying Boats that were built under contract by aircraft manufacturers as 'Felixtowe' flying boats. In April 1918, with the formation of the RAF, all Naval air assets were handed over to the new service, and the base became an RAF station. The experimental seaplane work was stopped in 1919, but restarted in 1924 when the RAF's Marine Aircraft Experimental Establishment moved to Felixstowe; they stopped doing their own aircraft designs though. Do you know what rank your great-grandfather was?