A320 windshear memory item.

[channel4]

Dear all,

I am fully aware of the procedures when encountering windshear on t/off and Go around, my question is with regards to when out of the windshear and the need to then clean up the aircraft.

On t/off for example, imagine just after V1 you have windshear alert. Therefore you have to follow the procedure until you finally get out of the windshear, lets say in this case at 2500 AGL. On your MCDU the thrust red/accel alt were both set at 1700 AGL.

Can someone please help me with the order of cleaning up the aircraft. I appreciate the question might look silly but I would like to know what happens if we have had to bust straight through Thrust reduction alt and ACCEL alt. Also what will happen to the managed speeds as we go through the shear and then out of it.

Is it:

Gear up,
then Lever climb,
then will the aircraft accelerate on its own and then we clean up or do i have to now push to level off and then clean up (because we have already passed accel alt on mcdu)?

please help!

many thanks, C4

[TyroPicard]

When clear of the windshear, look at the a/c config, both gear and flaps. Basically you should clean up in the same order as a normal T/O - gear, thrust, flaps. Gear first reduces the drag, CL thrust changes pitch mode from SRS to CLB or OP CLB , which commands acceleration for Flap retraction.

However there are possible complications..... With TOGA the a/c may well accelerate rapidly, so you must keep speed and speed trend awareness: if the arrow is big and you are getting near Vmax then select CL thrust first (or even less than CL if you judge it to be necessary), but be aware of possible deceleration with Gear and CONF3, or CONF FULL on a G/A. You can select CL again when everything is back under control.

On a G/A the order is Flap 3, Gear, CL thrust, Flaps.

The managed speed target will remain at V2 while in SRS - the windshear has no effect on that.

[channel4]

Thanks for the reply TP. :ok:

Your clean up schedule makes perfect sense to me but i'm still a little confused in one area.

According to FCTM and as I have understood, for a standard take-off with no windshear or problems etc, SRS is maintained until ACCEL ALT. If for example our THRUST RED ALT was 1500' and our ACCEL ALT was at 3000', at Thrust Red Alt when we select LVR CL we still maintain SRS hence Thrust Climb//SRS on FMA. Only at ACCEL Alt does the pitch reduce and speed increase to 250 or predetermined climb speed and we clean up on schedule with FMA reading Thrust CL//Climb or OP CL.

Therefore I do not understand when you say "CL thrust changes pitch mode from SRS to CLB or OP CLB , which commands acceleration for Flap retraction", and this is where my confusion lies if you have to bust through the ACCEL ALT in case of windshear.

Do you mean that if the windshear on climb out takes you past the ACCEL ALT, so in our case we are finally clear of windshear at lets say 4000' and put the gear up, then in this case only when you select LVR CL SRS will then change to climb/open climb? hence THRUST RED/ACCEL ALT automatically become at the same altitude?

The retraction schedule you say makes perfect sense to me, its just my confusion of when the new ACCEL ALT will be and how to achieve this!

Thanks for your help!! :ok:

C4

[channel4]

....or maybe its just a case of LVR CL and then just decrease pitch attitude manually and accelerate and clean up like after a GPWS manouver?