Using the simbrief profiles from here, the fuel calculation is off. Using something like P05, does not calculate enough fuel in the FMC. Either is the profile off or the calculation in FMC. I have to up the fuel by 5T on the flight from EDDF to OMDB, which is about 10% more, to get to what I would like to have, about 5T on landing.
Wrong subforum: should go into systems.
This is causing further issues with flights done with OnAir and fuel planning.