ATC TCAS Panel
The aircraft has two ATC transponders (XPDR) which are controlled by a control panel (ATC/TCAS) on the center pedestal.
Only the selected XPDR operates.
The XPDR automatically responds to requests:
- From the ATC, to ensure effective air traffic surveillance.
- From other aircraft that have a TCAS, to ensure that traffic alerts are triggered.
The XPDR is capable of elementary surveillance (ELS) and enhanced surveillance (EHS). It transmits the following data to the ATC center:
- Supplied by the ADRs:
- The aircraft 24 bit address
- The aircraft altitude
- The flight number
- The RA report
- The indicated airspeed
- The Mach number
- The barometric vertical speed
- Supplied by the IRs:
- The magnetic heading
- The roll angle
- The ground speed
- The track angle
- The track angle rate
- The inertial vertical speed
- The selected altitude and barometric reference settings supplied by the FCUs.
- Both XPDR are electrically supplied but do not operate.
- Selected XPDR operates.
- In flight : Selected XPDR operates.
- On ground : Selected XPDR only operates in mode S (Selective aircraft interrogation mode).
This switch selects XPDR 1 or 2.
Currently only 1 is available in the FBW A32NX for Microsoft Flight Simulator.
ALT RPTG Switch
- The XPDR sends barometric standard altitude data.
- No altitude data transmission. If the TCAS is installed, the upper ECAM displays "TCAS STBY" in green.
- The flight crew presses this button to send the aircraft identification signal.
- The window displays the selected code.
- The flight crew uses the keypad to set the code assigned by ATC.
- The flight crew uses this key to clear the code display.
- Note: As long as the four figures of the new code are not entirely written, the previous code remains.
ATC FAIL Light
- This light comes on if the selected XPDR fails.
TCAS knows the following threat categories:
- Other intruders - white outlined diamond
- Proximate intruders - white diamond
- Traffic Advisory (TA) - amber circle
- Resolution Advisory (RA) - red square
TCAS mode selector:
- If the ALT RPTG switch is ON and the transponder is not on STBY RAs, TAs and proximate intruders are displayed. Default position.
- TCAS only provides Traffic Advisory. Used in case of degraded aircraft performance (engine failure, landing gear extended, or approach on parallel runways).
- All RAs are converted into TAs. TAs, proximate and intruders are displayed if the ALT RPTG switch is ON and the transponder is not on STBY.
- "TA ONLY" memo is displayed on the NDs.
- TCAS is on standby.
- Proximate and other intruders are displayed only if a TA or RA is present, and they are within 2.700 ft above and 2.700 ft below the aircraft.
- Proximate and other intruders are displayed even if no TA or RA is present (full time function).
- The altitude range is –2.700 ft to +2.700 ft.
- Same as ALL, except that the other intruders are displayed if within 9.900 ft above and 2.700 ft below the aircraft.
- Same as ALL, except that the other intruders are displayed if within 9.900 ft below and 2.700 ft above the aircraft.