2.2.2 Primary flight display and flight mode annunciation
The captain and first officer both have a primary flight display at their disposal. This is a display on which primary flight information is shown such as an artificial horizon with which the attitude of the aircraft is shown compared to the horizon. The air speed, the rate of descend or climb, pressure altitude and radio height, heading and flight path information are also presented. In addition, the display provides information by means of flight mode annunciations, that are shown at the top in the primary flight display and that indicate the mode in which the automatic flight system is operating and what can be expected from the system. This information is essential for pilots to stay aware of the status of the automated control processes and the behaviour of the aircraft that can be expected. The left announcement refers to the autothrottle and the centre and right announcements refer to the horizontal and vertical flight path of the aircraft.
The flight director roll and pitch bar and the status of the autopilot are presented, if engaged, on the primary flight display. See illustration 3 for the layout of a primary flight display.