In the Airbus A320 and most modern aircraft, wind speed and direction are typically calculated and displayed through the aircraft’s Air Data Inertial Reference Unit (ADIRU) or Air Data Inertial Reference System (ADRIS).

Here’s a simplified explanation of how wind speed is calculated in the A320:

1. The A320 is equipped with multiple sensors that measure parameters such as airspeed, angle of attack, and total air temperature. These sensors are part of the ADIRS, which collects and processes data related to the aircraft’s movement through the air.
2. By comparing the heading and track data, the system can determine the wind component affecting the aircraft’s movement.
3. Using the ground speed, true airspeed, heading, and track information, the ADIRS calculates the wind speed and direction relative to the aircraft’s position. This calculation involves vector addition and trigonometric calculations to determine the component of the aircraft’s motion caused by the wind.

The green arrow indicating wind direction is only displayed when the wind speed exceeds 2 knots. If the display does not receive data for either wind speed or direction, dashes replace the numerical values on the display.

ND Display of winds

• Wind arrow indicates “Magnetic direction”
• Digital indications state “True direction” of wind

NORTH REF P/B is not available in new A320s.