im in descent now but the plane is not descending. do i have to manualy dial in the altitude in the autopilot?adamYou cant truley understand flying until you have actually tasted and felt it.

Affirmative,The plane won't descent until you tell it to by rotating the alt knob. If you are in VNAV, the plane will descend after crossing the T/D waypoint, and you have moved the knob to a lower alt. If not in VNAV, you have to active LVL CHG or V/S after rotating the knob to begin your descent.