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airsp
23rd Jan 2012, 16:48
Hi there,

I'm just wondering which FMA is displayed during REACTIVE WS RECOVERY PROCEDURE.

Example : During landing, ALT FCU displays 1500ft
At 1000ft, REACTIVE WINDSHEAR

Manoeuver :
- Pitch
- TOGA

Does FMA diplay "SRS / ALT" in order to catch 1500ft ?
Or, as detecting a reactive ws, the fma will tend to overshoot the go-around altitude ?

Thank you

rudderrudderrat
23rd Jan 2012, 17:39
Hi airsp,

Apparently "The protection envelope is from just after lift-off until 1300` on take-off and from 1300` to 50` for landing. In both cases, at least CONF 1 must be selected." - but I can't find the FCOM ref.

So it will capture 1500 ft.

DutchOne
23rd Jan 2012, 19:09
In case of WS during approach you'll go TOGA and follow SRS, right!
FMS sees this as a GA with WS. FMA will be as a GA, what is:

MAN TOGA, SRS (vertical), GA TRK (lateral).

(ALT is armed and will be shown in blue under the SRS)

The only difference is that the SRS allows a higher pitch limit (22.5 degrees on 330) because of the WS.

Normally at THR RED ALT you would put the thrust levers to the CLB detent, but because you are in WS you will not do that.

At ACC ALT, SRS makes space for ALT (green). If the thrust levers are still in the TOGA detent, TOGA thrust will still be given (A/THR is still not active) and you'll speed up very fast passing VMO within seconds (remember that you are still configured).

Rudderrudderrat was right about the WS detection up to 1300', so in the last 200' there will be no warning anymore, however if your speed trent is still all over the place, you know that you are still in WS.

Advise ATC of intentions! :}

Natstrackalpha
26th Jan 2012, 14:44
In case of WS during approach you'll go TOGA and follow SRS, right!
FMS sees this as a GA with WS. FMA will be as a GA, what is:

MAN TOGA, SRS (vertical), GA TRK (lateral).

(ALT is armed and will be shown in blue under the SRS)

The only difference is that the SRS allows a higher pitch limit (22.5 degrees on 330) because of the WS.

Normally at THR RED ALT you would put the thrust levers to the CLB detent, but because you are in WS you will not do that.

At ACC ALT, SRS makes space for ALT (green). If the thrust levers are still in the TOGA detent, TOGA thrust will still be given (A/THR is still not active) and you'll speed up very fast passing VMO within seconds (remember that you are still configured).

Rudderrudderrat was right about the WS detection up to 1300', so in the last 200' there will be no warning anymore, however if your speed trent is still all over the place, you know that you are still in WS.

Advise ATC of intentions! http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/badteeth.gif


Love your post.