4-2 Vertical modes
Vertical Speed (VS)
In the VS mode, the aircraft climbs with the selected (VS) vertical speed to the ALT SEL altitude.
The vertical speed mode engages automatically when a VS value greater than 100 feet per minute is set.
When the VS mode is engaged, the altitude hold mode is armed for altitude capture.
The VS value is displayed in the VS window above the VOR/LOC and LAND switches. The value can be set by the knob under the window.
Level Change (LVLCH)
When the LVLCH mode is active, the aircraft climbs to the ALT SEL altitude with a constant vertical speed of 2500 feet per minute (fpm).
The LVLCH mode can only be activated by the corresponding button.
Profile Mode
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Altitude Hold Mode (ALT HLD)
The ALT HLD is automatically armed when the VS or the LVLCH modes are activated.
It also can be activated manually by the corresponding button.
The ALT HLD value can be set by the knob below the ALT SEL window. The selected altitude is displayed in this window.