Originally Posted by
Broomstick Flier
Not only that, Abbey Road, but also, with the passing of years and all the abuse that the aircraft are subjected (small indentations, skin irregularities, structural repairs, etc) the aerodynamic reality begins to differ from the projected/theoretical data used to create performance tables and graphs. The FMC factor can be used to adjust the fuel calculations to these effects.
Well, the question I have is if the FMC uses this factor only for fuel calculations or also for descent and climb profiles for Vnav.