The Airbus A320 is fitted with one or two Multiscan weather radar systems with a Predictive WindShear (PWS) function and a weather hazard prediction function. The flight crew can display weather data on the NDs in either ARC or ROSE mode.
This switch sets one radar to ON or turns both radars to OFF.
Note: If only one radar is installed on the aircraft, either:
- a “INOP” or “DEACT” sticker replaces the “2”, or
- a “ON/OFF” Radar sw replaces the “1/OFF/2” Radar sw.
Note: If only one radar is installed on the aircraft, no weather image is displayed on the Navigation Display (ND) when the “1/OFF/2” SYS sw is set to “2”.
This knob adjusts the sensitivity of the radar.
CAL is the normal position of the knob :
- When in Multiscan Automatic mode and gain set to CAL, the radar automatically adjusts the gain according to various parameters (aircraft altitude, geographical area, season, time of the day) to obtain the best weather display.
- When in Manual mode and gain set to CAL, the radar adjusts the gain to a calibrated setting.
Display mode selector
- WX : Weather mode : Colors indicate the intensity of precipitation (black for the lowest intensity, green, amber and red indicate progressively higher intensity).
- WX+T : Weather and Turbulence mode : The ND indicates precipitation and turbulence areas. Turbulence areas are displayed in magenta (within 40 NM).
- TURB : Turbulence mode : The ND only displays turbulence areas in magenta (within 40 NM).
- WX+T+HZD : Weather, Turbulence and Hazard mode (recommended position) : The ND indicates precipitation, turbulence areas in magenta (within 40 NM) and hazard prediction risk areas. Hazard prediction function is only available when the MULTISCAN sw is set to AUTO. Note: When MULTISCAN sw is set to MAN, WX+T+HZD mode is equivalent to WX+T mode.
- MAP : Map mode : The radar operates in ground mapping mode: black indicates water, green indicates the ground, and amber indicates cities and mountains.
- This knob adjusts the antenna tilt when MULTISCAN sw is set to MAN.
- Zero indicates the horizon reference provided by the IRS.
- AUTO : Activates Multiscan mode. Multiscan controls the tilt automatically and combines two scans done at different tilt angles to optimize weather detection and minimize ground clutter.
- MAN : When set to MAN, the crew can manually adjust the tilt by using the TILT knob.
The Ground Clutter Suppression (GCS) switch is spring-loaded to the AUTO position.
- AUTO :
- If MULTISCAN sw is set to AUTO, the radar is in normal use. Ground clutter is not displayed on the screen.
- If MULTISCAN sw is set to MAN, the GCS sw has no utility. Ground clutter is displayed on the screen.
- OFF : Ground clutter is displayed on the screen.
- AUTO : Activates the Predictive WindShear function in accordance with activation conditions (Refer to FCOM for Windshear Alerts Above 50 feet).
- OFF : The Predictive WindShear function is off.