Chris, If you are that keen to join the RAF I support the view suggesting that No1 you join your local Air Cadet Squadron, there is a bit of marching and the rest, but you certainly will have the opportunity to go flying and gliding somewhere if you are interested. You already have a suggestion for Exeter and if I can work out how PM's work I will send you the name and phone number of the Devon PFA strut co-ordinator who may be able to give you more local advise.
Good luck and enjoy yourself
Mike