Originally Posted by
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.
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.