QFE and QFF MET

QFFQFF —Static pressure at MSL calculated from QFE using actual temperature lapse rates is QFEQFE —Static pressure measured at an aerodrome corrected to mean sea level using actual temperature lapse rates. If you do not know the temperature lapse rate, this means this calculation cannot be achieved, unless there is no correction to be made (i.e. the aerodrome is at mean sea level already) in which case the QFEQFE —Static pressure measured at an aerodrome and QFFQFF —Static pressure at MSL calculated from QFE using actual temperature lapse rates (and indeed, QNHQNH —Static pressure at MSL calculated from QFE using ISA temperature lapse rates) will be identical.