Abstract: A method for performing performance prediction with respect to a vertical flight plan. A system performs performance prediction with respect to a vertical flight plan of an aircraft that includes determining which vertical flight plan rules of a plurality of vertical flight rules that have been loaded in a predictions processor are active by monitoring for criteria that are used to initiate or terminate one or more of the vertical flight plan rules. Aircraft state is predicted at waypoints along a lateral flight path in view of active vertical flight plan rules, and the predicted aircraft state is updated within an integrated flight plan database that stores prediction performance data associated with the aircraft's flight.