A320 ADIRS CONTROL PANEL

A320 ADIRS Control Panel

ON BAT LIGHT

Batteries supply at least one ADIRU. The ON BAT light also comes on for a few seconds at the beginning of a complete IRS alignment. The ON BAT light does not come on in the case of a fast alignment.

Note: When the aircraft is on ground and if at least one ADIRU is supplied by aircraft batteries:

  • An external horn sounds
  • The ADIRU and AVNCS lights come on amber on the EXTERNAL POWER panel.

ON BAT light will not illuminate when one of the following applies:

  • All three ADIRUs are on, and not supplied by batteries, or 
  • All three ADIRUs are off.

IR pb

  • ON: IR 1(2)(3) is on. No light. When pressed, turns off the IR 1(2)(3).
  • OFF: IR 1(2)(3) is off. White OFF light comes on. When pressed, turns on the IR 1(2)(3).
  • FAULT light: IR 1(2)(3) is failed. Associated with the following ECAM alert: NAV IR 1(2)(3) FAULT(Refer to procedure). When IR 1(2)(3) FAULT light flashes, the attitude and heading information may be recovered in ATT mode. When IR 1(2)(3) FAULT light is steady, the IR 1(2)(3) is lost. When pressed, turns off the IR 1(2)(3). The FAULT light goes off.

IR MODE Selector

  • OFF: ADIRU 1(2)(3) is not energized. Both the IR 1(2)(3) data and the ADR 1(2)(3) data are not available.
  • NAV: IR 1(2)(3) operates in NAV mode IR 1(2)(3) provides full inertial data to the aircraft systems.
  • Note: ADR 1(2)(3) provides full air data to the aircraft systems.
  • ATT: IR 1(2)(3) operates in ATT mode. IR 1(2)(3) only provides attitude and heading data (if entered by the flight crew). The navigation data are not available. The heading must be entered through the MCDU and has to be reset frequently (about every 10 min). During the flight, if the IR mode selector is set from NAV to ATT or NAV to OFF, the NAV mode is lost for the remainder of the flight.

ADR pb

  • ON: ADR 1(2)(3) is on. No light. When pressed, turns off the ADR 1(2)(3).
  • OFF: ADR 1(2)(3) is off. White OFF light comes on. When pressed, turns on the ADR 1(2)(3).
  • FAULT light: ADR 1(2)(3) is failed. Associated with the following ECAM alert: NAV ADR 1(2)(3) FAULT(Refer to procedure). When pressed, turns off the ADR 1(2)(3). The FAULT light goes off.