Allows you to set an altitude to be alerted when you reach it. The altitude can be above or below you.
NOTE: It uses GPS altitude which is not as accurate as your primary altimeter. Your copilot is just suggesting to check your primary altimeter when she thinks you are close.
Setting an altitude alert is very similar to setting a decision height alert although there won’t be callouts. She will just tell you when you are near that altitude. This is useful if a controller tells you to climb or descend to a certain altitude.