catsplaystation;
so really no big deal in fuel burn between 30 & 40 is there ?
This is a question which should be asked of any operator who runs and actually uses their FOQA Program. We asked the question ourselves for the 320 fleet types and came up with "essentially no difference", certainly not enough to warrant reduced flap settings for the sake of fuel savings.
Other considerations may enter into an operational decision to use reduced flap as a matter of SOPs, but fuel savings, in my view based upon extensive data, should not be one of them.