Oh yes, and there are three papers for each exam. All I have to do is turn up, and as long as one of the CAA authorised people are there, just do the exam. They usually just ask which paper I want 1,2 or 3, and let me get on with it - no checks as to if I've sat and failed that paper before (not that I've failed any). Having said that, the failed papers are also kept on file, so someone probably would notice eventually if I sat the same one twice.
No idea what happens if you fail all three. Probably have to wait until they make new ones - after all, they must change them at least every few years surely. I think many schools make you do some kind of remedial training before allowing you a second or third stab at the exam anyway.