Just to Clarify
Newer Aircraft:
VLS: "Computed by the FAC based on FMS weight data, and on aerodynamic data as a backup, and corresponds to 1.13VS....."
Older Aircraft:
VLS: "Computed by the FAC, based on aerodynamic data...."
So computation is still done by the FAC but now using the FMS weight data.
From the Older "Aerodynamic Data"
FCOM DSC-22_40-30:
"The accuracies of the various minimum and maximum speeds are functions of the accuracy with which the FAC computes aircraft gross weight. Normal accuracy for VLS in CONFIG FULL is about +-3kts"
So this basically means that the VLS and hence VAPP is going to be much more accurate in the newer aircraft.
Last edited by Airmann; 25th Oct 2015 at 13:29.