PFD – Primary Flight Display

[Ref Pilot’s Handbook of Aeronautical Knowledge, FAA-H-8083-25B Page 8-12, 8-13]

PFD (Primary Flight Display) is one of the important elements in glass cockpit as a kind of Electronic Flight Display (EFD). It replaces the traditional “six pack” instruments.


Typical PFD

On the lift side of the screen is Airspeed Tape. It is not only showing airspeed in color-coded format, it is also showing TAS at the bottom; In the middle of the screen, Attitude Indicator spans the entire width of the PFD; On the right side of the screen is the Altimeter tape, it is showing the altitude in a tape with a black box in the center. Further right of the altimeter tape is is Vertical Speed Indicator (VSI); Below the Attitude Indicator is the Heading Indicator (a.k.a HSI- Horizontal Situation Indicator);

Turn Indicator, is showing quite different from traditional analog one – Rate of turn is combined into the Turn indicator and Inclinometer is combined into the Attitude Indicator.


  • Outside Air Temperature (OAT) is detected by the OAT probe and then feed into Air Data Computer (ADC) for calculation of TAS;
  • Attitude Indicator receives its information from the Attitude Heading and Reference System (AHRS);
  • Heading data is measured by magnetometer, which feeds information to the AHRS for further calculation before showing on PFD; 
  • Turn Indicator’s data is measured by accelerometers, which feeds information to the AHRS for further processing before showing on PFD




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