How to - Weather Radar (WXR) / Terrain Awareness and Warning System (TAWS) Operation

SYSTEM OVERVIEW

The Surveillance (SURV) system consists of the following system that perform surveillance functions:

• Traffic Collision Avoidance System (TCAS)

• Transponder (XPDR)

• Weather Radar (WXR) system

• Terrain Awareness and Warning System (TAWS)

This FAQ will cover the WXR and TAWS features of the SURV system. For TCAS, and XPDR systems, see the How to - Change Transponder / TCAS Modes via the Surveillance (SURV) MFD Page guide instead.

SURV - CONTROLS AND INDICATORS

The SURV system functions can be controlled via

1. SURV Panel on the Pedestal

2. SURV Page on the on the MFD

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1. SURV Panel on the Pedestal

For the purpose of this guide, we are only interested in the WXR SYSTEMS, ELEVN, VD AZIM and G/S Mode pushbutton of this panel.

• G/S Mode Pushbutton: Toggles the GPWS (Mode 5) function which monitors for excessive descent below the glide slope. A white OFF light is on when this is switched off.

• WXR TAWS SYS1 / 2 Pushbuttons: Toggles the primary SURV system responsible for interpreting Weather Radar Antennae data.

• VD AZIM Knob: Push to select AUTO mode (default position). Pull to select manual AZIM mode. In manual mode, rotate to adjust AZIM value ^∘ as shown by a white line on ND.

• WXR ELEVN/TILT Knob: Push to select AUTO mode (default position). Pull once to select ELEVN mode (not simulated), and again to select TILT mode.
  In TILT mode, rotate knob to adjust tilt value ^∘ and the lateral WX image on ND.

  Note: Sim API limitations prevent full simulation and display of WXR on the VD.

  Modern systems constantly sweep multiple beams at different angles simultaneously and blend them into a 3D volumetric memory buffer. As such you are not mechanically adjusting the radar dish in real-time via the controls.
  
  Instead, you are telling the computer to bias the vertical calculation from the 3D memory buffer by y^∘ upward or downward, or x^∘ to the left or right relative to the calculated flight path.

  
  The Sim Weather API only provides top-down weather overlay at various altitudes. The lack of available data limits any weather depiction on the VD.

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2. SURV Page on the MFD

For the purpose of this guide, we are only interested in the WXR and TAWS CONTROLS sections of this page.

To access the SURV page on the MFD,

• Select SURV from the MFD Page Options List at the top left corner of the MFD, OR

• Press the SURV shortcut key on the KCCU

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CHANGING WXR MODES - MFD SURV CONTROLS PAGE

• WXR toggle: Toggles the Weather Radar (WXR) system between AUTO and OFF. When set to OFF, the respective system display, warnings and audio alerts are disabled.

• PRED W/S toggle: Toggles the Predictive Windshear System (PWS) between AUTO and OFF. When set to OFF, the respective system display, warnings and audio alerts are disabled.

• TURB toggle: Toggles the Turbulence Detection (TURB) system between AUTO and OFF.

• GAIN toggle: Toggles between AUTO or Manual (MAN) gain control for the WXR.*

• MODE toggle:  Toggles the radar function between Weather display (WX) and ground mapping (MAP).*

• WX ON VD toggle: Toggles between AUTO or OFF the display of weather on the Vertical Display (VD).*

• ELEVN/TILT Option List: Toggles between AUTO or Manual (MAN) control of elevation (ELEVN)* mode or WXR tilt (TILT).
  In TILT mode, enter the desired tilt value ^∘ to bias the lateral WX image on ND upwards (+) or downwards (-).
  
  * = Not available in sim currently due to limitations of the sim weather API.

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CHANGING TAWS MODES - MFD SURV CONTROLS PAGE

• TERR SYS toggle: Toggles the terrain awareness and display (TERR) functions between ON and OFF. When set to OFF, the respective system display, warnings and audio alerts are disabled.

• GPWS toggle: Toggles the Ground Proximity Warning System (GPWS) functions between ON and OFF. 

• G/S MODE toggle: Toggles the GPWS (Mode 5) function which monitors for excessive descent below the glide slope. When set to OFF, the respective system display, warnings and audio alerts are disabled.

• FLAP MODE toggle: Toggles the GPWS (Mode 4B) functions which monitors for appropriate flaps configuration at low altitude in landing phase. When set to OFF, the respective system display, warnings and audio alerts are disabled.

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RESET ALL SURV MODES TO DEFAULT SETTING - MFD SURV PAGE

When clicked, the DEFAULT SETTINGS button automatically sets all the WXR, TAWS, TCAS and XPDR settings to their default position on both MFDs. A confirmation dialog is necessary to confirm selection. For WXR and TAWS sections, when pressed,

• WXR system is set to AUTO

• PRED W/S function is set to AUTO.

• TURB function is set to AUTO

• GAIN function is set to AUTO

• MODE function is set to WX

• ELEVN/TILT Option List is set to AUTO

• WX ON VD is set to AUTO

• TERR SYS mode is set to ON

• GPWS system is set to ON

• G/S MODE system is set to ON

• FLAP MODE system is set to ON

 
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