RAF airfoil designs

Living in Ottawa, Canada, I've had the opportunity to view original and museum-quality Great War aircraft. The quality of the engineering and construction of aircraft like the Sopwith 2.F1, Triplane and Snipe immediately struck me; I'm not a member of the "wooden stick and canvas" school when it comes to aeroplanes like these. Although aeronautical engineering was new and there was a lot still to be learned, there was good science behind the engineering of later WW1 aircraft. There are usually references to "RAF Aerofoil No.---" in descriptions of British aircraft, but I don't think I've ever read the details of how these worked. My impression is of a large number of tested airfoil shapes that could be selected from for a particular use. Or was the number simply assigned to the next airfoil listed for a specific aircraft design? If the former, were they wind-tunnel tested? I know that there were a small number of wind tunnels available. Were the designs done by the RAE or RAF (Royal Aircraft Factory)? Anybody know?

Thanks!

Ed; I can't give you specific info but generally speaking, as various countries militarys began to appreciate the potential uses of aircraft they set up aviation departments. These offices would ask manufacturers to submit info on their aircraft including design specs and airfoils. (During wartime this became mandatory.) These offices would arbitrarily assign numbers to airfoils as the info was recieved. Aftere WWI most such depts' reorganized and reassigned airfoil no.s. In some cases they set up their own engineering and test facilities to check designs and reassign no.s. Since then it's an ongoing process. Hope this helps a little.