At one time the Vintage glider club had one or two WW1 aircraft drawings, I looked at a Sopwith 1 and half stutter rudder drawing and some thing else, When they achive was at Lasham. When I help move the Drawings from Hatfield to Bicester the then Achivist didnt know of the drawings. But unless you went through the drawings which where a bit mixed up you wouldnt know what was there. So they might still be in store.
Dave