In Vertical Speed Mode, the flight director acquires and maintains a Vertical Speed Reference. Current aircraft vertical speed (to the nearest 100 fpm) becomes the Vertical Speed Reference at the moment of Vertical Speed Mode activation. This mode may be used for climb or descent to the Selected Altitude (shown above the Altimeter) since Selected Altitude Capture Mode is automatically armed when Vertical Speed Mode is selected.

When Vertical Speed Mode is activated by pressing the VS Key on the AFCS Mode Controller or accessing the AFCS Control window on the PFW and touching the VS Button, ‘VS’ is annunciated in green in the AFCS Status Box along with the Vertical Speed Reference. A Vertical Speed Reference Bug corresponding to the Vertical Speed Reference is shown on the indicator.