CUNIM is quite right, we ALL should have give you a few pointers a bit sooner. Apologies, young man.
Anyway, the advice above is very sound.
It's a bit of a bone of contention but there ARE other avenues into ATC (of a slightly different sort). The RAF (and to a lesser extent my own beloved RN) might be worth considering. A visit to your local careers office should help.
Hope this helps you. Oh, and if you have any other questions, just bung'em up here and I / we will TRY to respond a bit faster next time. Promise
Rgds BEX
