DOC AIRBUS | AMM A320FWEATHER RADAR SYSTEM - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
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1. General
The general purpose of the RDR-4000 weather radar system is to alert the crew from weather hazards encountered by aircraft on its potential flight path. Those may be: Adverse Weather conditions, Windshear, Turbulence.
Compared to the previous generation WXR (RDR4B), RDR-4000 main improvements/modifications are:
** ON A/C NOT FOR ALL The general purpose of the RDR-4000 weather radar system is to alert the crew from weather hazards encountered by aircraft on its potential flight path. Those may be: Adverse Weather conditions, Windshear, Turbulence.
Compared to the previous generation WXR (RDR4B), RDR-4000 main improvements/modifications are:
- use of a 3D buffer to collect weather information, Navigation Display (ND) is no more correlated with antenna scan
- independent display selection for CAPT and F/O
- automatic display of "on path" and "off path" weather cells
- constant elevation display mode replaces manual tilt mode
- enhanced turbulence detection
- "autonomous" reduction of ground clutter by using an embedded terrain database
- refine windshear (W/S) automatic activation logic.
2. Component Location
The components of the weather radar system are located in the aircraft as follows:
** ON A/C NOT FOR ALL The components of the weather radar system are located in the aircraft as follows:
Weather Radar - Component LocationNOTE: 1SQ1 is usually called weather Radar Processor (RP).
| FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||||
| 1SQ1 | XCVR-WEATHER RADAR, 1 | 109VU | 121 | 34-41-33 | |
| 3SQ | CTL UNIT-WEATHER RADAR | 11VU | 210 | 34-41-12 | |
| 7SQ | DRIVE-WR ANTENNA | 110 | 34-41-11 | ||
| 9SQ1 | MTG TRAY-WR XCVR, 1 | 109VU | 212 | 34-41-37 | |
| 11SQ | ANTENNA-WEATHER RADAR | 110 | 34-41-11 | ||
| 13SQ1 | XMTR/RCVR-WEATHER RADAR 1 | 110 | 34-41-51 | ||
3. System Description
The RDR-4000 weather radar is composed of items closely associated with its operation, such as peripherals supplying parameters, EFIS display units or maintenance functions.
The NDs are connected to the three Display Management Computers (DMC) and to the CAPT and F/O EFIS control panels of the Flight Control Unit (FCU).
The RDR-4000 weather radar is composed of items closely associated with its operation, such as peripherals supplying parameters, EFIS display units or maintenance functions.
NOTE: The weather radar image is shown independently on the CAPT and F/O Navigation Displays (ND).
The NDs are connected to the three Display Management Computers (DMC) and to the CAPT and F/O EFIS control panels of the Flight Control Unit (FCU).
NOTE: Each weather radar system receives data from 2 redundant Air Data/Inertial Reference Units (ADIRU). Inertial Reference System (IRS) data are essential for weather detection and windshear function.
A. General
The weather radar system, which complies with ARINC Characteristics 708A, consists of:
The weather radar system, which complies with ARINC Characteristics 708A, consists of:
- a weather radar transceiver (or Radar Processor) 1SQ1
- a weather transceiver mounting tray 9SQ1
- a dual weather radar control unit 3SQ
- a single weather antenna drive 7SQ
- a weather radar antenna 11SQ
- a weather radar transmitter/receiver 13SQ1.
(1) Weather radar transceiver (or Radar Processor)
The Honeywell RDR-4000 is an airborne X-Band weather radar system. Its function is to increase the flight crew's awareness by detecting and annunciating weather conditions that could disturb the correct development of the flight, primarily heavy precipitation, turbulence, and windshear. By providing automatic features, RDR-4000 allows to reduce crew workload.
The Honeywell RDR-4000 is an airborne X-Band weather radar system. Its function is to increase the flight crew's awareness by detecting and annunciating weather conditions that could disturb the correct development of the flight, primarily heavy precipitation, turbulence, and windshear. By providing automatic features, RDR-4000 allows to reduce crew workload.
B. Periphericals
(1) Digital serial data inputs
The weather radar transceiver receives digital serial data inputs from the following components:
The weather radar transceiver receives digital serial data inputs from the following components:
(a) Radio altimeter
The radio altimeter provides altitude information over two redundant ARINC 429 bus inputs to the RDR-4000 weather radar. This data is used in the predictive windshear function.
The radio altimeter provides altitude information over two redundant ARINC 429 bus inputs to the RDR-4000 weather radar. This data is used in the predictive windshear function.
(b) Air data reference
Two redundant ARINC 429 low-speed buses provide:
Two redundant ARINC 429 low-speed buses provide:
- airspeed data used for volumetric buffer processing and Predictive Windshear System (PWS) function
- altitude data used in elevation mode.
(c) Inertial reference
Two redundant ARINC 429 high-speed buses provide:
Two redundant ARINC 429 high-speed buses provide:
- pitch roll and drift angle data for the stabilization and control of the antenna
- hybrid position and altitude, speed, track/heading angle for volumetric buffer processing.
(d) Centralized Fault Display Interface Unit (CFDIU)
The RDR-4000 weather radar communicates with the CFDIU Low-speed ARINC 429 bus for maintenance purpose.
The RDR-4000 weather radar communicates with the CFDIU Low-speed ARINC 429 bus for maintenance purpose.
(e) EFIS control section
Two ARINC 429 buses provide the CAPT and F/O range selection and barometric reference selection (for selected altitude display in elevation mode).
The receiver/transmitter receives one bus from the CAPT EFIS control section and another one from the F/O EFIS control section.
Two ARINC 429 buses provide the CAPT and F/O range selection and barometric reference selection (for selected altitude display in elevation mode).
The receiver/transmitter receives one bus from the CAPT EFIS control section and another one from the F/O EFIS control section.
(2) Outputs
The weather radar transceiver provides the following outputs:
The weather radar transceiver provides the following outputs:
(a) Displays
The RDR-4000 weather radar is connected to the DMCs by an ARINC 453 bus to transmit the weather radar data.
All the weather and windshear data received by the DMCs are processed and displayed on CAPT and F/O NDs and PFD for caution and warning alert.
The RDR-4000 weather radar is connected to the DMCs by an ARINC 453 bus to transmit the weather radar data.
All the weather and windshear data received by the DMCs are processed and displayed on CAPT and F/O NDs and PFD for caution and warning alert.
1 The Navigation Display (ND) provides the following indications:
- weather radar image
- windshear events location in case of PWS alert
- mode messages reflecting mode CAPT and F/O selection on control panel (CAPT mode selection is indicated on CAPT ND, F/O selection is indicated on F/O ND).
2 The Primary Flight Display (PFD) indicates windshear visual alert in case of caution or warning alert.
NOTE: The Flight Warning Computers (FWC) and the FDIU receive RDR-4000 weather radar data through the DMCs. These data are used by the FWCs to display windshear function failure and windshear function de-activation. The FDIU records the windshear alert and failure.
C. General Technical Characteristics
The RDR-4000 weather radar system is mainly used to detect and localize various types of atmospheric disturbances and windshear events in the area scanned by the antenna. The system shows the disturbance intensity through the use of colors which vary with the atmospheric precipitation rate.
The disturbances are shown to the crew members on the NDs with different colors:
As the minimum display range is 10 NM, two yellow radials appear at the edges and start beyond the windshear (W/S) event.
The RDR-4000 weather radar system is mainly used to detect and localize various types of atmospheric disturbances and windshear events in the area scanned by the antenna. The system shows the disturbance intensity through the use of colors which vary with the atmospheric precipitation rate.
The disturbances are shown to the crew members on the NDs with different colors:
- black, green, yellow, red to quantify the precipitation rates
- magenta to represent the turbulence areas up to 40 NM.
As the minimum display range is 10 NM, two yellow radials appear at the edges and start beyond the windshear (W/S) event.
4. Power Supply
Energization of the system is through a 115VAC/400 Hz bus:
The system is supplied through this circuit breaker:
Energization of the system is through a 115VAC/400 Hz bus:
- 1XP via the busbar 101 XP-C for weather radar transceiver 1.
- control unit, transmitter/receiver unit and antenna drive.
The system is supplied through this circuit breaker:
A. Circuit Breakers Table
| PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 121VU | COM NAV/RADAR/1 | 5SQ1 | K13 |
5. Interface
A. Display Modes
RDR-4000 introduces 3D-Buffer technology, antenna scanning is no more correlated with ND display. The system will continuously scan the atmosphere in front of the aircraft from 0 to 60000 ft. That is the main difference compared to previous generation weather radar with which antenna scanning was limited to one tilt setting defined either automatically by the system or manually by the pilot and weather radar echoes detected over the plan defined by the antenna tilt position were synchronously displayed on ND.
In automatic mode, RDR-4000 provides to the ND all detected weather cells. Cells situated outside of aircraft vertical flight path (called OFF PATH weather cells) are displayed on ND with hatched colors while cells situated within aircraft vertical flight path (called ON PATH cells) are displayed in solid colors.
Pilots have also the capacity to select an altitude layer that will be extracted and displayed on ND, this is the constant elevation mode that should be used for weather cell analysis.
Due to the fact that a delay of 30 seconds is necessary to fill 3D buffer at system power-up, a new display OFF mode has been introduced in order to remove weather echo from the ND with system still actively scanning and updating its 3D buffer.
RDR-4000 introduces 3D-Buffer technology, antenna scanning is no more correlated with ND display. The system will continuously scan the atmosphere in front of the aircraft from 0 to 60000 ft. That is the main difference compared to previous generation weather radar with which antenna scanning was limited to one tilt setting defined either automatically by the system or manually by the pilot and weather radar echoes detected over the plan defined by the antenna tilt position were synchronously displayed on ND.
In automatic mode, RDR-4000 provides to the ND all detected weather cells. Cells situated outside of aircraft vertical flight path (called OFF PATH weather cells) are displayed on ND with hatched colors while cells situated within aircraft vertical flight path (called ON PATH cells) are displayed in solid colors.
Pilots have also the capacity to select an altitude layer that will be extracted and displayed on ND, this is the constant elevation mode that should be used for weather cell analysis.
Due to the fact that a delay of 30 seconds is necessary to fill 3D buffer at system power-up, a new display OFF mode has been introduced in order to remove weather echo from the ND with system still actively scanning and updating its 3D buffer.
B. Operational behavior/antenna scanning
(1) Activation of WX/PWS and TURB functions are made through respectively by the WX/PWS switch and TURB switch.
System behavior regarding activation of WX or W/S detection depends on control panel selection and Air/Ground or qualifier status:
System behavior regarding activation of WX or W/S detection depends on control panel selection and Air/Ground or qualifier status:
(a) If system switch is set to OFF, system is supplied, BITE interactive mode is available but the system will not scan, whatever the position of other control knobs.
(b) If one system is selected with system switch then operational state of the system depends on Ground/Air condition and control knobs position:
1 On ground:
- When both CAPT and F/O display mode selectors are set to OFF then the system will not scan ("standby" state) until qualifier logic becomes valid (Automatic activation). Once qualifier became valid the system will scan for WX (including TURB) and W/S detection.
- If CAPT or F/O display mode selector is set to a mode different than OFF, then WX (including TURB) and W/S detections are activated and system will scan (Manual activation).
2 In air:
- System always scans for WX (including TURB) detection and for W/S in the PWS activation area.
A. Transceiver FIN: 1-SQ-1 FIN: 1-SQ-2
The RDR-4000 radar transceiver (or Radar Processor) converts the receiver output signal from the transmitter/receiver unit to an usable output for display. It provides positioning data to the antenna drive and mode control data to the transmitter receiver unit.
The RDR-4000 radar transceiver (or Radar Processor) converts the receiver output signal from the transmitter/receiver unit to an usable output for display. It provides positioning data to the antenna drive and mode control data to the transmitter receiver unit.
B. Weather Radar Antenna Flat Plate
The weather radar antenna flat plate:
The weather radar antenna flat plate:
- transmits energy into a narrow, accurately directed beam with minimal sidelobe levels
- receives the echo-returned energy.
C. Weather Radar Transmitter/Receiver Unit
The weather radar transmitter/receiver unit provides the means for:
The weather radar transmitter/receiver unit provides the means for:
- generating and transmitting a nonlinear, frequency modulated (FM) waveform
- receiving return echoes that then will be processed by the radar transceiver.
D. Weather Radar Control Unit
The weather radar control unit provides all controls necessary to select radar mode and ancillary pilot input.
The weather radar control unit provides all controls necessary to select radar mode and ancillary pilot input.
7. Operation
A. Operation
(1) Weather radar modes
The weather radar system uses the principle of radio echoing. It works at a normal frequency of 9345 MHz. The transmitter/receiver unit generates a microwave energy in the form of electromagnetic pulses via X-band wave guide to the antenna.
When these pulses intercept an appropriate target, part of the energy is reflected back to the weather radar antenna then to the transmitter/receiver. Then signal is outputted from transmit/receiver unit to radar transceiver through a coaxial link and processed by the radar transceiver in order to convert it in a displayable data.
The elapsed time between the transmission of the wave and the reception of the echo allows determining the target distance (it takes around 12.36 microseconds for the electromagnetic wave to travel out and back for each nautical mile of target range).
The azimuth and elevation position of the target is detected by the position of the antenna. As the quantity of energy reflected to the antenna is proportional to the target density, the different levels of atmospheric disturbances are shown on the displays by different colors.
The detection of the turbulence areas is based on the Doppler Phenomenon.
The weather radar system uses the principle of radio echoing. It works at a normal frequency of 9345 MHz. The transmitter/receiver unit generates a microwave energy in the form of electromagnetic pulses via X-band wave guide to the antenna.
When these pulses intercept an appropriate target, part of the energy is reflected back to the weather radar antenna then to the transmitter/receiver. Then signal is outputted from transmit/receiver unit to radar transceiver through a coaxial link and processed by the radar transceiver in order to convert it in a displayable data.
The elapsed time between the transmission of the wave and the reception of the echo allows determining the target distance (it takes around 12.36 microseconds for the electromagnetic wave to travel out and back for each nautical mile of target range).
The azimuth and elevation position of the target is detected by the position of the antenna. As the quantity of energy reflected to the antenna is proportional to the target density, the different levels of atmospheric disturbances are shown on the displays by different colors.
The detection of the turbulence areas is based on the Doppler Phenomenon.
| -------------------------------------------------------------------------- |
| ! LEVEL DETECTED ! PRECIPITATION RATE ! COLOR OF ECHOES ! |
| !------------------------!-----------------------!-----------------------! |
| ! Z1 < 20 dBz ! less than 1 mm/h ! black ! |
| ! 20 less than or equal ! from 1 to 4 mm/h ! green ! |
| ! to Z2 < 30 dBz ! ! ! |
| ! 30 less than or equal ! from 4 to 12 mm/h ! yellow ! |
| ! to Z3 < 40 dBz ! ! ! |
| ! 40 less than or equal ! 12 mm/h and above ! red ! |
| ! to Z4/Z5 < 50 dBz ! ! ! |
| !------------------------!-----------------------!-----------------------! |
| ! Turbulence ! 5 m/s ! magenta ! |
| -------------------------------------------------------------------------- |
| Table 1: Color Correspondence Table |
(2) 3D buffer
The RDR-4000 radar antenna continuously scans the volume ahead of the aircraft (from 0 to 60000 ft) and stores weather returns in a 3D buffer.
The weather information stored in the 3D buffer is used for display on ND. So with the 3D buffer, the weather display is no more correlated with the radar antenna position like for conventional weather radar.
Use of a volumetric display buffer which stores swaths of data that can be retrieved in either horizontal slices or in vertical slices allows to improve weather detection by reducing ground clutter and providing multiple views of the reflectivity data.
The RDR-4000 radar antenna continuously scans the volume ahead of the aircraft (from 0 to 60000 ft) and stores weather returns in a 3D buffer.
The weather information stored in the 3D buffer is used for display on ND. So with the 3D buffer, the weather display is no more correlated with the radar antenna position like for conventional weather radar.
Use of a volumetric display buffer which stores swaths of data that can be retrieved in either horizontal slices or in vertical slices allows to improve weather detection by reducing ground clutter and providing multiple views of the reflectivity data.
(3) Windshear mode
The WXR/PWS, by a Doppler mode, determines the wind field ahead of the aircraft. By a mathematical treatment, the system determines the hazard factor (so called F-factor) related to the danger of a windshear event. An hazard factor exceeding a value of 0.13 and within 5 NM ahead of the aircraft is considered as the presence of a dangerous event and a corresponding windshear alert is generated.
The display of windshear hazard consists of an icon of red and black bands superimposed on the radar returns. These events are dangerous during takeoff and landing maneuvers. So when weather system is activated (one system selected through 1/OFF/2 selector switch on control panel), PWS function is automatically activated with a dedicated logic called qualifier logic. Contrarily to WX function that requires around 30 seconds after start of antenna scanning, PWS operation is "real beam" and therefore PWS detection is available as soon as antenna starts scanning.
Qualifiers also permit to prevent undesired radar emission on ground and to protect personal.
The WXR/PWS, by a Doppler mode, determines the wind field ahead of the aircraft. By a mathematical treatment, the system determines the hazard factor (so called F-factor) related to the danger of a windshear event. An hazard factor exceeding a value of 0.13 and within 5 NM ahead of the aircraft is considered as the presence of a dangerous event and a corresponding windshear alert is generated.
The display of windshear hazard consists of an icon of red and black bands superimposed on the radar returns. These events are dangerous during takeoff and landing maneuvers. So when weather system is activated (one system selected through 1/OFF/2 selector switch on control panel), PWS function is automatically activated with a dedicated logic called qualifier logic. Contrarily to WX function that requires around 30 seconds after start of antenna scanning, PWS operation is "real beam" and therefore PWS detection is available as soon as antenna starts scanning.
Qualifiers also permit to prevent undesired radar emission on ground and to protect personal.
(4) Turbulence detection
The turbulence detection has been improved with the new pulse waveforms and digital signal processing.
The radar system detects moderate and severe turbulence from the blind range (less than 1 NM) to 40 NM from the aircraft and 20 NM laterally on either side from the aircraft centerline.
The turbulence detection has been improved with the new pulse waveforms and digital signal processing.
The radar system detects moderate and severe turbulence from the blind range (less than 1 NM) to 40 NM from the aircraft and 20 NM laterally on either side from the aircraft centerline.
(5) Weather radar control unit
The face of the control unit is provided with integral lighting. The INTEG LT/ MAIN PNL & PED potentiometer enables lighting adjustment. The potentiometer is located on the panel 111VU, at the left aft section of the center pedestal 11VU.
The weather radar control unit includes the following controls:
The face of the control unit is provided with integral lighting. The INTEG LT/ MAIN PNL & PED potentiometer enables lighting adjustment. The potentiometer is located on the panel 111VU, at the left aft section of the center pedestal 11VU.
The weather radar control unit includes the following controls:
(a) A WXR/PWS control switch, item 1, with three stable positions 1/OFF/2, which enables the activation of system 1 or 2 when installed.
(b) A TURB control switch, item 2, with two stable positions AUTO/OFF.
This switch must be usually set to AUTO, the OFF position allows flight crew to remove turbulence events (displayed in Magenta) from the display for decluttering purpose.
This switch must be usually set to AUTO, the OFF position allows flight crew to remove turbulence events (displayed in Magenta) from the display for decluttering purpose.
(c) A GAIN knob, item 3, which allows to adjust the intensity of weather displayed colors around automatic position for weather cell reflectivity analysis.
(d) A CAPT DISPLAY or F/O DISPLAY selector switch, item 4.
Each crew member can choose between the following modes :
Each crew member can choose between the following modes :
- OFF : in this mode, PWS function is active in the activation zone (during take-off and landing), no weather echo is displayed except when a windshear alert is triggered.
On ground, both display mode switches have to be set to OFF in order to prevent any radar emission. If one crew member selects a display mode different than OFF when one system is selected, then antenna is scanning and emitting.
As soon as system detects the Air state, system will automatically scan and update the 3D-buffer but no weather radar echo will be displayed until pilots change display mode. - ALL : in this mode, ON PATH and OFF PATH weather data are displayed, windshear and turbulence detections are enabled
- ON PATH : in this mode, only ON PATH weather is displayed, windshear and turbulence detections are enabled
- ELEVN: in this mode, each crewmember can display the weather data at the altitude selected with ELEVN rotary knob. The windshear detection is enabled but turbulence presentation is not available
- MAP : in this mode, only ground echoes are displayed on ND, windshear detection is still enabled.
(e) An ELEVN knob, item 5.
When the ELEVN display mode is selected, item 4, each crew member can control the weather altitude layer to be displayed on ND.
When the ELEVN display mode is selected, item 4, each crew member can control the weather altitude layer to be displayed on ND.
B. Utilization of Controls and Indicating
(1) Operation of radar areas
Special precautions to be taken.
On ground, on the weather radar control unit, before moving WXR/PWS control switch from OFF to 1 or 2 position (in dual configuration) and selecting a DISPLAY mode different than OFF, make sure that within an arc of +/- 135° on either side of the aircraft centerline, there is:
Special precautions to be taken.
On ground, on the weather radar control unit, before moving WXR/PWS control switch from OFF to 1 or 2 position (in dual configuration) and selecting a DISPLAY mode different than OFF, make sure that within an arc of +/- 135° on either side of the aircraft centerline, there is:
- No one and no large metallic obstacle (such as a hangar) within a distance lower than 5 m from the antenna in movement
- No fuel within a distance less than 1.5 m from the antenna in movement.
(2) Weather data displayed in normal operation
Due to the fact that RDR-4000 introduces new display modes, a new set of WXR messages to be displayed on ND has been defined on Electronic Information System 2 (EIS2).
The table below contains details messages that can be displayed in WXR control data area according to actions on control panel (CP) and associated meaning when the system is in normal operation.
Due to the fact that RDR-4000 introduces new display modes, a new set of WXR messages to be displayed on ND has been defined on Electronic Information System 2 (EIS2).
The table below contains details messages that can be displayed in WXR control data area according to actions on control panel (CP) and associated meaning when the system is in normal operation.
| ------------------------------------------------------------------------------- |
| ! LOCATION ! INDICATION ! COLOR ! PILOTS ACTION ON CP ! MEANING ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 1st row ! MAN GAIN ! WHITE ! GAIN knob set to a ! ! |
| ! ! ! ! position different ! ! |
| ! ! ! ! from AUTO ! ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 2nd row ! PWS SCAN ! GREEN ! Display mode set to ! No weather echoes ! |
| ! ! ! ! OFF, aircraft during ! displayed on ND ! |
| ! ! ! ! takeoff or approach ! System scanning for ! |
| ! 3rd row ! ! ! (PWS qualifiers ! W/S events, PWS ! |
| ! ! ! ! valid) ! function enabled ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 2nd row ! PWS SCAN ! GREEN ! Display mode set to ! No weather echoes ! |
| ! ! ! ! OFF, aircraft during ! displayed on ND ! |
| ! 3rd row ! ! ! TO or APPR (PWS qua- ! System scanning for ! |
| ! ! ! ! lifier valid) ! W/S events, PWS ! |
| ! ! ! ! ! function enabled ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 2nd row ! MAP ! BLUE ! Display mode set to ! Only ground returns ! |
| ! ! ! ! MAP ! detected on ND ! |
| ! 3rd row ! ! ! ! ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 2nd row ! ELEVN ! BLUE ! Display mode set to ! Weather layer detec- ! |
| ! ! ! ! ELEVN, FCU baro set- ! ted at 12000 ft ! |
| ! 3rd row ! 12000 FT ! BLUE ! ting set to QFE/QNH ! displayed on ND ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 2nd row ! ELEVN ! BLUE ! Display mode set to ! Weather layer detec- ! |
| ! ! ! ! ELEVN, FCU baro set- ! ted at FL120 displa- ! |
| ! 3rd row ! FL120 ! BLUE ! ting set to STD ! yed on ND ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 2nd row ! WX ALL ! GREEN ! Display mode set to ! ON PATH and OFF PATH ! |
| ! ! ! ! ALL, TURB control ! weather displayed on ! |
| ! 3rd row ! ! ! switch set to AUTO ! ND ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 2nd row ! WX ALL ! GREEN ! Display mode set to ! ON PATH and OFF PATH ! |
| ! ! ! ! ALL, TURB control ! weather displayed on ! |
| ! 3rd row ! TURB OFF ! BLUE ! switch set to OFF ! ND, turbulence areas ! |
| ! ! ! ! ! not displayed on ND ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 2nd row ! PATH WX ! GREEN ! Display mode set to ! ON PATH weather ! |
| ! ! ! ! ON PATH, TURB ! displayed on ND ! |
| ! 3rd row ! ! ! control switch ! ! |
| ! ! ! ! set to AUTO ! ! |
| !----------!------------!-------!----------------------!----------------------! |
| ! 2nd row ! PATH WX ! GREEN ! Display mode set to ! ON PATH weather ! |
| ! ! ! ! ON PATH, TURB ! displayed on ND, ! |
| ! 3rd row ! TURB OFF ! BLUE ! control switch set ! turbulence areas not ! |
| ! ! ! ! to OFF ! displayed on ND ! |
| !----------!------------!-------!----------------------!----------------------! |
(3) Weather data displayed when a failure is detected
The table below contains details of the messages displayed in case of failure and associated operational impact
The table below contains details of the messages displayed in case of failure and associated operational impact
| ------------------------------------------------------------------------------- |
| ! LOCATION ! INDICATION ! MEANING ! OPERATION IMPACT ! |
| !----------!------------!----------------------!------------------------------! |
| ! ! ! DU internal breakdown! WXR/PWS is still available ! |
| ! ! ! leading to cancel- ! but display WXR data is no ! |
| ! 4th row ! NO WXR ! lation of radar ! more available. ! |
| ! ! ! echoes ! If a W/S event is detected, ! |
| ! ! ! ! audio alert can be triggered ! |
| !----------!------------!----------------------!------------------------------! |
| ! ! ! ! This flag is displayed in ! |
| ! ! ! ! case of internal or external ! |
| ! ! ! ! failure. ! |
| ! ! ! ! In some particular cases of ! |
| ! ! ! ! external fault, WX function ! |
| ! ! ! ! is lost and PWS function ! |
| ! ! ! ! still available. ! |
| ! ! ! ! In this case green PWS SCAN ! |
| ! ! ! ! message will be displayed ! |
| ! 4th row ! WXR R/T ! Weather radar ! when PWS function is activa- ! |
| ! ! ! transceiver or ! ted. ! |
| ! ! ! transmitter/receiver ! If W/S event is detected, ! |
| ! ! ! failure ! audio and PDF alert could be ! |
| ! ! ! ! triggered but W/S icon cannot! |
| ! ! ! ! be displayed on ND. ! |
| ! ! ! ! However in the majority of ! |
| ! ! ! ! the cases, WXR R/T fault will! |
| ! ! ! ! result in the lost of WXR and! |
| ! ! ! ! PWS function. ! |
| !----------!------------!----------------------!------------------------------! |
| ! 4th row ! WXR ANT ! Weather radar ! In this case, both WX and PWS! |
| ! ! ! antenna failure ! functions are lost ! |
| !----------!------------!----------------------!------------------------------! |
| ! ! ! ! In this case, no weather data! |
| ! ! ! ! can be displayed on ND. ! |
| ! ! ! ! PWS function is still availa-! |
| ! ! ! ! ble. Green PWS SCAN message ! |
| ! ! ! ! will be displayed when PWS ! |
| ! ! ! ! function is active (together ! |
| ! 4th row ! WXR CTL ! Weather radar control! with the red WXR CTL flag) ! |
| ! ! ! panel failure ! If a W/S alert is detected, ! |
| ! ! ! ! "WXR CTL" flag will be remo- ! |
| ! ! ! ! ved during the duration of ! |
| ! ! ! ! the alert. W/S icon on ND, ! |
| ! ! ! ! W/S warning on PDF and audio ! |
| ! ! ! ! alert will be available. ! |
| !----------!------------!----------------------!------------------------------! |
| ! ! ! ! This failure is managed inde-! |
| ! ! ! ! pendently on CAPT side and ! |
| ! ! ! ! F/O side. ! |
| ! ! ! ! For example, if CAPT FCU bus ! |
| ! ! ! ! is no more received by WXR ! |
| ! ! ! ! system, WXR RNG message will ! |
| ! ! ! ! be displayed on CAPT ND mea- ! |
| ! ! ! FCU input failure ! ning that no WX echo could be! |
| ! 4th row ! WXR RNG ! (WXR doesn't receive ! displayed on this ND. ! |
| ! ! ! EFIS selected range ! In this case, PWS function is! |
| ! ! ! input) ! still available. Green PWS ! |
| ! ! ! ! SCAN message will be dis- ! |
| ! ! ! ! played when function is ! |
| ! ! ! ! still active. ! |
| ! ! ! ! If W/S event is detected, PFD! |
| ! ! ! ! and audio alert will be trig-! |
| ! ! ! ! gered but no W/S icon can be ! |
| ! ! ! ! displayed. ! |
| !----------!------------!----------------------!------------------------------! |
| ! ! ! ! In this case, PWS function ! |
| ! ! ! ! only is lost (ND flag is ! |
| ! 4th row ! PREC W/S ! PWS function failure ! associated with ECAM message)! |
| ! ! ! ! WX function is still availa- ! |
| ! ! ! ! ble. ! |
| !----------!------------!----------------------!------------------------------! |
| ! ! ! ! This flag is displayed on ! |
| ! 4th row ! WRX TEST ! WXR system test ! ground only when system test ! |
| ! ! ! ! is performed together with ! |
| ! ! ! ! test pattern. ! |
| ------------------------------------------------------------------------------- |
(4) Weather data messages displayed on the NDs
8. Test
A. Self-Test
A quick check of the correct operation of the WXR/PWS installation can be performed by activating the test function:
A quick check of the correct operation of the WXR/PWS installation can be performed by activating the test function:
- either through the Centralized Fault Display System (CFDS) by applying the procedure Radar functional test on the Multipurpose Control and Display Unit (MCDU).
- or by pressing the TEST pushbutton switch located on face of the transceivers. When a fault is detected, it is stored and made available to the front panel Liquid Crystal Display (LCD) display when the TEST pushbutton switch is pressed. The LCD is used as a maintenance aid to check the operational status of the WXR/PWS.
Once this TEST pushbutton switch is pressed, the LCD shows "TEST IN PROGRESS".
The self-test takes from 5 to 10 seconds to complete.
At the end of the test, the LCD shows "RADAR OK" "INPUT OK" if no faults were detected in either the radar or inputs connections.
Pressing the return button returns to the fault main menu.
* If radar faults were found during the self-test, the following messages can be displayed:R/T FAULT ANT FAULT CON FAULT WG SWITCH FAULT INDICATOR FAULT COOLING FAULT
* If inputs faults were found during the self-test, the following messages can be displayed:NO RAD ALT NO ALTITUDE IN NO AIR DATA IN NO HEADING INPUT.
B. BITE Description
(1) General
The BITE facilitates maintenance on in-service aircraft. It detects and identifies a failure related to the system.
The BITE of the WXR/PWS is situated in the radar transceiver and through two ARINC 429 low-speed buses (an input bus from the CFDIU and an output bus to the CFDIU).
The BITE:
The BITE facilitates maintenance on in-service aircraft. It detects and identifies a failure related to the system.
The BITE of the WXR/PWS is situated in the radar transceiver and through two ARINC 429 low-speed buses (an input bus from the CFDIU and an output bus to the CFDIU).
The BITE:
- transmits permanently weather radar system status and its identification message to the CFDIU
- memorizes the failures which occurred during the last 63 flight legs
- monitors data inputs from the various peripherals (EFIS control panel, ADIRUs, RAs)
- transmits to the CFDIU the result of the tests performed and self-tests
- can communicate with the CFDIU through the MCDU menus.
- acquires the general maintenance parameters (UTC, date, A/C ident...) and command codes from the CFDIU.
- an ARINC 429 low speed bus from the CFDIU.
The data sent by the CFDIU are:--------------------------------------------------------- ! LABEL ! PARAMETER ! FORMAT ! --------------------------------------------------------- ! 125 ! UTC ! BCD ! ! 155 ! AIRCRAFT CONFIGURATION 1 ! DISC ! ! 156 ! AIRCRAFT CONFIGURATION 2 ! DISC ! ! 227 ! COMMAND ! DISC ! ! 260 ! DATE ! BCD ! ! 301 ! AIRCRAFT IDENT ! ISO ! ! 302 ! AIRCRAFT IDENT ! ISO ! ! 303 ! AIRCRAFT IDENT ! ISO ! --------------------------------------------------------- - an ARINC 429 low speed output bus to the CFDIU.
The data sent to the CFDIU are:--------------------------------------------------------- ! LABEL ! PARAMETER ! FORMAT ! --------------------------------------------------------- ! 354 ! LRU IDENTIFICATION ! ISO ! ! 356 ! FAULT MESSAGES ! ISO ! ! 377 ! EQUIPMENT IDENTIFICATION ! BCD ! --------------------------------------------------------- The BITE can operate in two operating modes: * in normal mode, to report continuously the failures of all classes, depending on the maintenance flight phase, * in interactive mode, to provide an interactive dialog with an operator using an MCDU.
NOTE: The WXR/PWS complies with the specification ABD0048 issue C.
(2) Normal mode
During the normal mode the BITE monitors cyclically the status of the WXR/PWS. It transmits its information to the CFDIU during the concerned flight.
In case of fault detection the BITE stores the information in the fault memories. These items of information are transmitted to the CFDIU by an ARINC 429 message with label 356.
During the normal mode the BITE monitors cyclically the status of the WXR/PWS. It transmits its information to the CFDIU during the concerned flight.
In case of fault detection the BITE stores the information in the fault memories. These items of information are transmitted to the CFDIU by an ARINC 429 message with label 356.
(3) Interactive mode
The interactive mode can only be activated on the ground and through the line key adjacent to the Radar 1 item, presented on one of the pages of the system report test menu of any MCDU.
This mode enables communication between the CFDIU and the BITE of the weather radar transceiver by means of the MCDU.
The interactive mode is composed of:
The interactive mode can only be activated on the ground and through the line key adjacent to the Radar 1 item, presented on one of the pages of the system report test menu of any MCDU.
This mode enables communication between the CFDIU and the BITE of the weather radar transceiver by means of the MCDU.
The interactive mode is composed of:
- LAST LEG REPORT
This report contains the fault messages related to the external or internal failures (class 1 and 2) recorded during the last flight leg.
The following tables give the list of the failure messages which can be reported and indicate the failure class assigned to them as defined by the CFDIU standard.------------------------------------------------------------- ! Reported Internal Failures ! !-----------------------------------------------------------! ! MESSAGE (i = 1 or 2) ! CLASS ! ATA ! ------------------------------------------------------------- ! WXRi_RP (1SQi) ! 1 ! 34-41-33 ! ! WXR_ANT_DRIVE (7SQ) ! 1 ! 34-41-11 ! ! WXR_CTL_PNL (3SQ)/<CR>WXRi (1SQi) ! 1 ! 34-41-12 ! ! WXRi_RTU(13SQi) ! 1 ! 34-41-34 ! ------------------------------------------------------------- -------------------------------------------------------------------- ! Reported External Failures ! !------------------------------------------------------------------! ! MESSAGE (i = 1 or 2) ! CLASS ! ATA ! !------------------------------------------------------------------- ! ADIRU1 (1FP1) BUS_ADR/<CR>WXR1 (1SQ1) ! 3 ! 34-12-34 ! ! ADIRU3 (1FP3) BUS_ADR/<CR>WXRi (1SQi) ! 3 ! 34-12-34 ! ! ADIRU1+3 (1FP1+3) BUS_ADR/<CR>WXR1 (1SQ1) ! 1 ! 34-12-34 ! ! ADIRU1 (1FP1) BUS_IR/<CR>WXR1 (1SQ1) ! 3 ! 34-12-34 ! ! ADIRU3 (1FP3) BUS_IR/<CR>WXRi (1SQi) ! 3 ! 34-12-34 ! ! ADIRU1+3 (1FP1+3) BUS_IR/<CR>WXR1 (1SQ1) ! 1 ! 34-12-34 ! ! FCU(2CA)BUS_CP-L/<CR>WXRi(1SQi) ! 1 ! 22-81-12 ! ! FCU(2CA)BUS_CP-R/<CR>WXRi(1SQi) ! 1 ! 22-81-12 ! ! CFDIU1 (1TM1)/WXRi (1SQi) ! 3 ! 31-32-34 ! ! RA1 (2SA1)/WXRi (1SQi) ! 3 ! 34-42-33 ! ! RA2 (2SA2)/WXRi (1SQi) ! 3 ! 34-42-33 ! ! RA1 (2SA1)+RA2 (2SA2)/<CR>WXRi (1SQi) ! 1 ! 34-42-33 ! ! QUALIFIER_B/WXRi(1SQi) ! 1 ! 79-33-11 ! ! POWER SUPPLY INTERRUPT ! 1 ! 24-00-00 ! --------------------------------------------------------------------
NOTE: Failure of one radio altimeter is a class 3 failure whereas it becomes a class 1 failure when two radio altimeters are faulty.
- PREVIOUS LEGS REPORT
This report contains the fault messages related to the external or internal failures (class 1 and 2) recorded during the previous 63 flight legs. - LRU IDENTIFICATION
Allows to display the P/N and the S/N of the equipment. - GND SCANNING
Based on the monitoring and fault analysis during flight, provides information of the failures detected while using this function.
The WXR/PWS peripheral monitoring and internal cycle tests are used to detect transient failures.
By pressing the line key adjacent to the failure message, the operator is allowed to the corresponding Trouble Shooting Data. The peripheral monitoring and WXR/PWS internal cyclic tests are used to detect transient failures. - TROUBLE SHOOTING DATA
Provides correlation parameters and snapshot data concerning the failure displayed in the LAST LEG REPORT and PREVIOUS LEGS REPORT. - CLASS 3 FAULTS
Allows to display the class 3 faults recorded during the last flight leg. - GROUND REPORT
Allows to present the class 1, 2 or 3 internal failures detected on ground.
These failures differ from those displayed on the LAST LEG REPORT and CLASS 3 FAULTS.
By pressing the line key adjacent to the failure message, the operator is allowed to access to the corresponding Trouble Shooting Data. - TEST
Allows a check of the correct operation of the WXR/PWS on ground.
This test can be performed by:
- either selecting the test function on the LCD of the WXR transceiver
- or through the Centralized Fault Display System (CFDS) by selecting on the MCDU the test function on the radar 1 main menu page.
At the end of the BITE TEST, the test pattern comes into view.
NOTE: If a failure of the windshear system is detected during the BITE TEST, the windshear flags come into view.
If the failure does not affect the radar mode, the test pattern stays available.
If the failure affects the radar mode, nothing is shown.
All the information displayed on the MCDU during the BITE TEST configuration can be printed by the printer (Ref. 45-40-00). If the failure does not affect the radar mode, the test pattern stays available.
If the failure affects the radar mode, nothing is shown.