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Strange, idle increase from 20% to 45% when switching anti-Ice ON

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Hi all


Very happy with the CRJ 700 flying on VATSIM.


As controller I have the Thrustmaster TCA Airbus. Calibrated including the reversers with the inbuilt calibration page in the CRJ tablet; works very good.


When I switch on the two engines, N1 goes to about 20% idle, very good.

Then I switch on the Anti-ice ON allready on ground, the engines N1 goes up to 45% N1. Switching Anti-ice OFF returns to 20% N1.


Is this normal or schould I only put Anti-Ice ON during flight?





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For what I know, the N1 should not be linked to whether or not anti ice ist s enabled.

But i think anti ice is switched on during takeoff (affects perfomance calculations) under certain icing conditions, otherwise is kept off while not in flight

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The attached table shows the correct usage of the anti-ice system.


As for the engine RPM: In flight and only when selecting WING A/I ON the engine idle RPM is raised automatically by the FADEC to ensure that the airpressure in the pneumatic duct is sufficient for effective wing anti-icing. This results in a considerable increase of idle thrust. On ground, the selection of COWL A/I and/or WING A/I has no influence on engine RPM. Unfortunately, this is not modeled correctly.




COWL              ON                                                                                                  OFF


On ground     Temp- <= 10°C                                                             If not required

                       AND     visible moisture                                               OR

                       OR        contaminated surface                                     Entering parking stand


In flight           In icing conditions                                                        If not required


                        ICE message



WING                ON                                                                                                    OFF


On ground     Temp- <= 5°C                                                                 If not required

                       [AND     visible moisture OR contaminated runway]   OR

                       AND        for takeoff only                                                After landing (leaving the runway)


In flight           [In icing conditions AND IAS < 230 KIAS]                    If not required


                        ICE message


Edit: Copyright reasons - sorry :)


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