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Chapter 13. Ice and rain protection

Table of Contents

13.1. Double AOA heat fail
13.2. Single pitot probe heat or static port heat fault
13.3. Multiple pitot heat failures
13.4. Single AOA or TAT heat fault
13.5. Probe heat computer failure
13.6. Window heat fault
13.7. Engine anti-ice valve fault
13.8. Wing anti-ice valve open when commanded closed
13.9. Wing anti-ice valve closed when commanded open
13.10. Wing anti-ice valves fail to close after ground self-test
13.11. High pressure detected when wing anti-ice turned on

13.1. Double AOA heat fail

If two AOA probes are affected by icing, the computers may erroneously deselect the remaining good ADR. Switching off one of the affected ADRs leaves the system in the state described in Section 10.5, “ADR disagree”.

[QRH AEP.A-ICE, FCOM PRO.AEP.A-ICE]

13.2. Single pitot probe heat or static port heat fault

The ADR associated with the failed probe or port should be considered unreliable. ADR1 or ADR2 can be replaced with ADR3 using air data switching. If using standby instruments with ADR3 unreliable, air data information must be monitored closely.

[ANTI ICE CAPT(F/O)(STBY) PITOT(L(R) STAT), FCOM PRO.AEP.A-ICE]

13.3. Multiple pitot heat failures

The issue with loss of anti-ice on more than one pitot probe is that it is possible that the two unprotected pitot probes will ice up at the same time and provide erroneous but coherent data. This leads to a situation where the ADR associated with the remaining protected probe is locked out despite being the single correct source.

Obviously, the first thing to do is to avoid icing conditions. If there is a working ADR connected to a protected probe, turn one of the ADRs associated with an unprotected probe off. This ensures that an “ADR DISAGREE” ECAM caution is triggered by significant speed discrepancies and ensures that the protected ADR will not be automatically deselected.

If pitot heat is lost on all probes, one of the ADRs should, again, be turned off to ensure the “ADR DISAGREE” ECAM caution is provided. If icing is expected, turn off a second ADR and be ready to apply unreliable airspeed procedures (see Section 2.3, “Unreliable airspeed (memory item)).

[ANTI ICE ALL(CAPT(F/O)+F/O(STBY)) PITOT, FCOM PRO.AEP.A-ICE]

13.4. Single AOA or TAT heat fault

No immediate operational effect.

[ANTI ICE CAPT(F/O)(STBY) AOA(TAT), FCOM PRO.AEP.A-ICE]

13.5. Probe heat computer failure

If applicable, deselect the affected ADR.

[ANTI ICE CAPT(F/O)(STBY) PROBES, FCOM PRO.AEP.A-ICE]

13.6. Window heat fault

No immediate operational effect.

[ANTI ICE L(R)(L+R) WINDSHIELD(WINDOW), FCOM PRO.AEP.A-ICE]

13.7. Engine anti-ice valve fault

If a valve fails to open when commanded, avoid icing conditions. If it fails to close when commanded, a thrust limit penalty applies.

[ANTI ICE ENG 1(2) VALVE OPEN(CLSD), FCOM PRO.AEP.A-ICE]

13.8. Wing anti-ice valve open when commanded closed

In the air, just allow the failed side to be continually anti-iced and use wing anti-ice on the working side when required. A thrust limit penalty will apply. On the ground, isolate and depressurise the pneumatic system on the failed side.

[WING ANTI ICE L(R) VALVE OPEN, FCOM PRO.AEP.A-ICE]

13.9. Wing anti-ice valve closed when commanded open

The wing anti-ice must be turned off to avoid asymmetrically de-icing the wings. Avoid icing conditions. If ice accretion does occur, landing distances and Vapp adjustments are in QRH IFP and speed must be maintained above the higher of VLS+10kt or Green Dot.

[WING ANTI ICE SYS FAULT, FCOM PRO.AEP.A-ICE, FCOM PRO.NOR.SUP.AW]

13.10. Wing anti-ice valves fail to close after ground self-test

Simply switch off the wing anti-ice with the push button. If the valves still do not close, see Section 13.8, “Wing anti-ice valve open when commanded closed”.

[ANTI ICE OPEN ON GND, FCOM PRO.AEP.A-ICE]

13.11. High pressure detected when wing anti-ice turned on

A thrust limit penalty is applied automatically.

[WING ANTI ICE L(R) HI PR, FCOM PRO.AEP.A-ICE]