BEagle is quite correct - The civil instructor rating is, and always has been, a FIR (flying instructor rating), it's probationary partner being the AFIR (assistant flying instructor rating). Under the JAA system the equivalents are the FI(A) (flight instructor(aeroplanes)) and the FI(A)(R) (flight instructor (aeroplanes) (restricted)). These european jhonnies do like their brackets!
In order to become a B2 (probationary) QFI (Qualified Flying Instructor) you would have to have continuous 'above average' assessments as a pilot and completed a six month course at the Central Flying School of the Royal Air Force. I think it is fair to say that, judging by the FI ratings that I have renewed/awarded over the last 15 years, 90% of AFIs would have lasted no more than 2 days at CFS.
FIs - KNOW YOUR PLACE!