When do you switch off the anti ice on A320?

[pineteam]

I remember the good old days not so long ago when our A320 were not equipped with ice detectors and the use of anti ice was based on what is written in the FCOM and common sense: You would approach a cloud and according to the TAT/SAT you will set the engines anti ice ON and when clearly out of the clouds, set the engines anti ice OFF. Simple as that, and never had or heard any issues on that matter. Nowadays all our aircraft are equipped with ice detection system which I agree is very helpful especially at night. My problem with that sometimes you will just fly into one thick cumulus for less than 10 seconds, so as per normal you will set the engines anti ice ON before entering the clouds and then when out of the cloud, you set the engines anti ice OFF again but because the probes of the anti ice system are still covered with ice the system will trigger an ECAM which could last a while until the ice is completed gone.. Now my understanding an anti ice system is used to PREVENT, not to remove ice. So when out of icing conditions there is no need to keep the anti ice system active. So what basically happens quite often is that I will switch OFF the engines anti ice system off when we are clearly out of the clouds but because the ECAM is triggered: ''ice detected'' some pilots believe the correct procedure in this case is to set the engines anti ice back ON until the 'memo '' ice not detected'' is displayed even tho it's sunny outside! And This memo last 190 seconds! I mean: Am I missing something there? Are we pilots or robots following blindly an ECAM? Please share your thoughts.

[vilas]

I remember the good old days not so long ago when our A320 were not equipped with ice detectors and the use of anti ice was based on what is written in the FCOM and common sense: You would approach a cloud and according to the TAT/SAT you will set the engines anti ice ON and when clearly out of the clouds, set the engines anti ice OFF. Simple as that, and never had or heard any issues on that matter. Nowadays all our aircraft are equipped with ice detection system which I agree is very helpful especially at night. My problem with that sometimes you will just fly into one thick cumulus for less than 10 seconds, so as per normal you will set the engines anti ice ON before entering the clouds and then when out of the cloud, you set the engines anti ice OFF again but because the probes of the anti ice system are still covered with ice the system will trigger an ECAM which could last a while until the ice is completed gone.. Now my understanding an anti ice system is used to PREVENT, not to remove ice. So when out of icing conditions there is no need to keep the anti ice system active. So what basically happens quite often is that I will switch OFF the engines anti ice system off when we are clearly out of the clouds but because the ECAM is triggered: ''ice detected'' some pilots believe the correct procedure in this case is to set the engines anti ice back ON until the 'memo '' ice not detected'' is displayed even tho it's sunny outside! And This memo last 190 seconds! I mean: Am I missing something there? Are we pilots or robots following blindly an ECAM? Please share your thoughts.
Generally engine anti ice is used th prevent icing and wing anti ice is used as a deice. So without ice detector engine anti ice was switched on prevailing conditions without any positive confirmation of icing but wing anti ice was only selected when visually ice was seen forming. I haven't got any information about A320 ice dection system but in some Boeing FBW it's based on ultrasonic vibration of the detector which gets altered when ice is formed and engine anti automatically comes on with intimation to pilot. Similarly it also goes off. Wing anti ice will be perhaps triggered at more severity. In reality it reduces the use of anti ice and saves fuel.

[FlightDetent]

@pinteam:

Some 'Quality' Departments accept and understand what you explained, agree to the reason and practicality too, in its entirety.

And then to resolve the dilemma an SOP gets published + enforced that E-AI shall not be turned off until the MEMO goes away. To keep the statistics of ECAM warnings clean. [@vilas - note the fuel, wear&tear and environmental efficiency of that)

[speedrestriction]

I do use the wing anti-ice on the 320 as, well, anti-ice. In conditions which seem likely to me to be conducive to the ice accretion (-20c to 0c in high moisture concentration) I select it before waiting for a buildup. Having flown turboprops for years I have a healthy suspicion of ice anywhere on an aircraft. My company don't have detectors and we still use the original method described by the OP for the engine AI. Seems to work just fine.

[Zar_1]

(Since the auto ice detect is an option)... in cases where you don't have it equipped... you'd rely on the visual lighted indicator in the front, right?

[Zar_1]

In the case of WAI/NAI, wouldn't it be better to be very liberal in its use (as in, use as frequently and as long as possibly needed)... since the consequences of not using at are very serious?

[vilas]

https://www.skybrary.aero/bookshelf/books/3404.pdf
May be this will help.

[leffsu]

yep!
When you clear of cloud,you can wait for the memo:“ice not detected”disappeared and then switch off the Engine An-ti Ice.
If you off the an-ti ice before it goes out that may trigger the ECAM SEVERE ICE DETECTED.

[Miniguppy]

Why do we have to turn the engine anti ice on during descent even if the SAT is below -40 degrees?

[AerocatS2A]

Low engine rpm makes it more susceptible to icing is my guess.

[tdracer]

Why do we have to turn the engine anti ice on during descent even if the SAT is below -40 degrees?
Because it's probably going to warm up as you descend, and unless someone is paying close attention you can get a significant engine ice accumulation before noticing and turning on engine AI.
As noted above, wing AI is basically a deicer, but engine is intended to prevent ice. If there is significant ice accumulation on the inlet prior to AI selection, the resultant ice shed can cause considerable engine damage. In a severe case it can cause fan damage, but even relatively small accumulations can play havoc with the fan duct acoustic panels when the fan slings it outward at high velocity.

[KSASVA]

I switch E-AI OFF when "Out of icing conditions + ICE NOT DETECTED memo", if the MEMO comes up while still flying in icing condition I will still keep E-AI ON.

[sonicbum]

I remember the good old days not so long ago when our A320 were not equipped with ice detectors and the use of anti ice was based on what is written in the FCOM and common sense: You would approach a cloud and according to the TAT/SAT you will set the engines anti ice ON and when clearly out of the clouds, set the engines anti ice OFF. Simple as that, and never had or heard any issues on that matter. Nowadays all our aircraft are equipped with ice detection system which I agree is very helpful especially at night. My problem with that sometimes you will just fly into one thick cumulus for less than 10 seconds, so as per normal you will set the engines anti ice ON before entering the clouds and then when out of the cloud, you set the engines anti ice OFF again but because the probes of the anti ice system are still covered with ice the system will trigger an ECAM which could last a while until the ice is completed gone.. Now my understanding an anti ice system is used to PREVENT, not to remove ice. So when out of icing conditions there is no need to keep the anti ice system active. So what basically happens quite often is that I will switch OFF the engines anti ice system off when we are clearly out of the clouds but because the ECAM is triggered: ''ice detected'' some pilots believe the correct procedure in this case is to set the engines anti ice back ON until the 'memo '' ice not detected'' is displayed even tho it's sunny outside! And This memo last 190 seconds! I mean: Am I missing something there? Are we pilots or robots following blindly an ECAM? Please share your thoughts.

Hi,

In addition to what has been posted already.
the functioning of the Ice detection system is described in Getting to Grips with Cold Weather Operations, section A3.3.2 The Airbus Dual Advisory Ice Detection System (DAIDS). Just google it and you can download the pdf.

[FlightDetent]

I think the dilemma still stands.

You engage the E-AI before entering the icing condition. Later you exit to VMC above the layer that did have actual ice, and ask for E-AI off.

As the ICE DET is still contaminated the ECAM complains until the frost evaporates, while the engine inlets are clear and not picking anything. Moreover, assuming an extreme case with some leftover deposits on the intake lips, putting the E-AI off at this stage reduces the probability of crust separation and fan interference.

There is no technical benefit of re-engaging the heating of engine intake leading edge once outside the icing conditions. It is even possible to speculate an edge case where active anti ice might reduce the margins from an undesirable aircraft state

Except the nice office people, lacking context and under indiscriminate pressure to tick boxes and polish all statistics, will come up with a rule to a) always follow the ECAM or b) never to turn off E-AI until the message ICE NOT DET shows up. To keep their spreadsheets clean and create even more quality data points to supervise.

Such is the pleasure of airline flying.



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