a320 Reactive Winshear activation question
 

Hi everyone,

As per Fcom, the Reactive Winshear systems activates 3 sec after liftoff.

However, in the Mems items for W/S, it states that after V1, thrust toga, wait until Vr to rotate.

How can the FAC gives warning from V1 to Vr, when it only works 3 sec after lift off?

Thanks

Reactive and predictive windshear alerting supplements our own judgment of windshear encounters.

Pred WS is inhibited after 100kts.

The FAC will not give a warning any warnings from 100kt till 50 ft

- Below 100kt: warning active
- Above 100 Kt: no warnings (pilot awareness)
- Below V1: reject the TO if large speed variations (pilot awareness)
- After V1 up to 50 Ft: no warnings (pilot awareness)
- Above 50 ft: warning active

You don't need any warning on take off run. Just look at your speed trend arrow. The arrow head which usually disappears in the forward end of the speed tape will make it's appearance again and start playing tricks. That's when either reject or TOGA.

thanks for your inputs. That confirms that there is no warining after 100kts, and it’s pilot decision to recognize windshear