Andy, RAF Fairford is no long fully operational and your chances of seeing anything is very remote. You do get the occasional U-2 coming in but these are few and far between. At Brize, you will see a lot more traffic, C130s, VC10 Tankers, Tristars etc and a few other goodies. Try parking somewhere along Station Road (A4095 out of the village towards Bampton) on the East end of the airfield.
Hope this helps and have a great day out.
Ian
Cosford Air Show on Sunday will be packed with planes. And people unfortunately.
Cheers ian thats really helpful info, do you get many fast jets etc tornado's?
Andy