Flight Sergeants have never been OR-8, though they'll often try and convince you otherwise!I didn't imagine it, I cant find any info on it being changed since the early 90's.
Any crabs know if the FSgt rank has been down graded by NATO?
The RAF have no rank equivalent to OR-8 having binned WO2 (I believe) at the start of WW2.
Flight Sergeant is and always was equivalent to Staff or Colour Sergeant (and Navy equivalent).
Always good for a wind up in joint messes though.