A Primary Flight Display, or PFD, is the modern aircraft instrument dedicated to flight information. Installed in cockpits equipped with an Electronic Flight Instrument System, it serves as the pilot's principal reference, presenting data on a single compact screen. By replacing arrays of traditional gauges with a coherent digital format, the PFD simultaneously delivers attitude, airspeed, altitude, heading and navigation cues, expanding the scope of information beyond a simple electronic attitude display. This consolidated, instantly readable picture reduces pilot workload, sharpens situational awareness and forms the backbone of contemporary glass-cockpit operations.
What is a PFD in aviation?
A Primary Flight Display or PFD is a modern aircraft instrument found in an aircraft equipped with an Electronic Flight Instrument System. It provides a digital display of important flight information, serving as the pilot's primary reference.
A primary flight display (PFD) is a modern aircraft instrument that is part of the electronic flight instrument system. It is built around a liquid-crystal display or CRT display device, and it provides a digital display of important flight information by combining the representations of older six-pack or "steam gauge" instruments onto a single electronic display. This unit is dedicated to flight information and provides the pilot's primary reference for flight information by displaying electronic attitude, flight mode annunciator, and heading indicator.
The PFD includes an attitude indicator (AI) surrounded by other flight parameters like airspeed tape on the left side of the AI and altitude and vertical speed references on the right side of the AI. It provides autopilot/flight director guidance, flight control system steering commands, and flight control system mode annunciation. The PFD displays airspeed (knots or Mach) and speed trend, altitude (baro and radio), vertical speed, and heading and track. It includes various scales and limits like bank limits and max sidestick deflection, as well as sideslip indication and sidestick order indication.
The PFD provides radio navigation (ILS, DME, etc. ), course deviation indicators, glide slope, and marker beacon annunciation. It displays FMGS deviations (vertical and lateral), excessive ILS deviation, and decision height set and annunciation. The PFD reduces pilot workload by streamlining cockpit layouts and simplifying pilot workflow, boosting situational awareness, and reducing the need for constant left-right up-down scan.
How does a PFD work in aviation?
A PFD works by combining information traditionally displayed on several electromechanical instruments onto a single electronic display. A PFD is built around a liquid-crystal or CRT display device and consolidates data that used to be shown on multiple analog instruments into one electronic screen. It is the pilot's primary reference for flight information because it brings together instantly all the information required for control of the aircraft and for horizontal and vertical navigation.
A PFD uses the pitot-static system, alpha vanes, and an air data computer to obtain and analyze altitude, airspeed, vertical speed, and angle-of-attack measurements, and it displays the results in a readable format. Glass flight-instrument displays are fed by pitot tubes, static ports, and the stall management yaw damper, so the components mounted in the airframe feed data to the screen.
A computerized signal generator translates the data into visible images, producing a multicolour digital display of attitude, airspeed, altitude, vertical speed, heading, flight path vector, and weather information while showing the aircraft's future path symbol at the centre and numerals plus a compass rose for heading at the bottom. The convention places the airspeed tape on the left side of the attitude indicator and altitude and vertical speed references on the right, so slip/skid and flight director symbols sit at the top and centre, simplifying the pilot workflow.
The Primary flight display provides autopilot engage annunciation, flight control system mode annunciation, fast-slow deviation or angle-altitude and excessive ILS deviation alert, radar altitude reading, marker beacon alert, and VOR, localiser, TACAN, RNAV or GNS deviation to guide ILS glideslope approaches and to show pre-selected altitude deviation. Synthetic vision overlays and GNS steering can be called up by the pilot while raw navigation data or weather can stay on the EHSI, and the representations of the older six-pack or steam-gauge instruments are combined on one compact display. By streamlining cockpit layouts and reducing the need for constant left-right up-down scan, the Primary Flight Display lowers pilot workload and enhances situational awareness in every phase of flight.
When I experienced the Primary Flight Display, I discovered that a small rearward force on the yoke would provoke the aircraft to fall below the horizon mark, and the upright velocity device complemented this by revealing the resulting drop. I learned to read its motions as the primary manifestation of the aircraft's movement and bank, the elevation strip on the right and the airspeed strip on the left both shift in part to the attitude signal, so comprehension of these linked cues became important for flying without visual indicators. The PFD itself gave my spatial position: a mild movement would sway the whole view pictorial, the velocity strip would diminish, and the moment I dropped below the line demarcation marking an ascent I could watch the elevation strip incrementing upward while the bearing signal complemented the picture.
Jim GoodrichPilot, Airplane Broker and Founder of Tsunami Air
Expert behind this article
Jim Goodrich
Jim Goodrich is a pilot, aviation expert and founder of Tsunami Air.
