Hey LCharnes,
FWIW If you do not already know this, the Brooklands Aero Clubhouse was built in 1932, funded by Brooklands Aviation Ltd (I think). Maybe there is some information there you can use in your research. There is mention of the 'Air & Airways' magazine having a presence there during the opening. Maybe check out said magazine?
Also, there were a couple of films made at Brooklands in the early-1930s. One was about auto racing, but the other - 'The Kings Cup' - was oriented around said air race and was filmed in 1932 shortly after the Aero Clubhouse was built (released in 1933?). There are supposed to be scenes from inside the Aero Clubhouse.
Also, there was a caricature made of Brooklsnds Aero Club in 1932 - "Our Flying Clubs No. 1 - Brooklands Aero Club" - that mentions the following people:
"Notable members of the club pictured here include the manager, A. Percy Bradley, Ian Stoddart-Barr, Sales Manager, Billy Massey, one of the directors in charge of the repair shop, Capt. H. Duncan Davis, Managing Director, Bob the barman (important!), Ginger Ruutz-Rees, K. Mistinger, S. A Thorne, instructor and acrobatic pilot, Flight Lieut W. E. P. Johnson a prominent exponent of blind flying and the chief instructor, George E. Lowdell"
So there was at least a bar. Assuming they were real people then maybe there are records that could help, left by or about some of them.
Otherwise, I ran across this 1938 floor plan of the Croydon main building. It would seem like there should be a plan of all such airport buildings?
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