Vertical alignment of a movable bridge with a doorway of an aircraft is achieved by moving a sensor disposed on the movable bridge in a generally downward direction so as to sense a position of an upper surface of the aircraft. The upper surface of the aircraft has a known elevational relationship relative to the doorway of the aircraft, which is used along with the sensed position to align an aircraft engaging portion of the movable bridge with the doorway. The method accommodates different heights of a same model of aircraft resulting from differences in the aircraft loads and is easily implemented using either contact or non-contact sensors.