Primary Flight Display Symbols
Lowest Selectable Speed
VLS is defined by the top of the amber strip along the speed scale. VLS is the minimum speed that provides an adequate margin above stall. It is the slowest speed the auto flight and auto thrust system will fly, if engaged. It provides a 1.2 G low speed buffet margin when above FL 200. During approach or below FL 200 provides a 1.23 VSTALL margin for landing. VLS on the PFD is a dynamic number computed by the FACs based on airplane configuration and load factor.
VLS in the MCDU is a static number generated by the FMGC based on predicted landing weight and selected landing flap configuration on the PERF APPR page (e.g., FLAPS 3 or FULL).