Vilas,

"reduction of THR RED / ACC ALT should be avoided"

Reduction from what? From Airbus recommend THR RED / ACC ALT's ? What are Airbus recommended THR RED / ACC ALT's?

This is a hole in our manual (company generated) which needs to be filled.

Airbus clarification in wind shear conditions recommended THRRED/ACC ALT of at least 1500ft and TOGA take off.

If a windshear is suspected, put 9999 in as acceleration altitude, and push (or pull) CLB when you're at your desired acceleration altitude, and still no shear.
Failing (forgetting) that, pull speed when CLB engages.

Vilas: Absolutely agree with what you're saying but the key is to minimize height loss as stressed in the note in the qrh and fctm.
So if SRS is there follow it, if it reverts to Op Clb/Clb pitch accordingly to keep climbing (full back if necessary)... basics.

ElitePilot
It is not that basic unless a thought is given to it. In WS when you are battling to centre the FDs you are not likely to notice the FMA change. Every one knows what to do when FDs are not there but to ignore the FDs because change in SRS to CLB requires preplanning.

Vilas,

Exactly.

We train pilots to follow the FD religiously. In only rare instances do we teach them to disregard FD commands. When sheite hits the fan, you get into a full blown windshear event, the FD in SRS is giving you good info - you follow it. When you reach ACC ALT as programmed in the box, it now gives you bad info - now you are to disregard it - that is asking a lot if a normal line pilot to absorb and respond correctly to in an incredibly stressful and dangerous environment.

Vilas, do you have an Airbus publication reference for setting 1500' ACC ALT as a precautionary windshear procedure? TIA

Mongo and xhamster
As mentioned by me earlier this was stated in the answer by airbus to me by name so I am not sure if I should post it in public but you can write an email to me.
xhamster
There is minimum 120ft ROC protection in CLB but the result of the battle between pitch and ROC may be uncertain.

Hello guys, is there any development in this regard?
Has any airbus publication updated this procedure?
in suspected windshear increase AA or be mindful to reset TOGA in case of FMA change during wind shear

Procedure remains same. If thrust is reduced before the shear then offcourse must select TOGA. PM has a important role. Mostly I have seen PM calling only winds speed and head or tail. I think key to survival is climb He must call climbing or descending as the case may be. Because if the aircraft is descending PF will require full back stick if he is not doing then it will serve as a reminder to do so. Also if aircraft speed is rapidly increasing it should be called so PF can fly above the FD to reverse the trend and then get back to FD. If speed is dropping should not be called because intuitively he will push forward which may be dangerous. In airbus AoA protection will look after low speed.

the 120ft ROC protection is only in SRS but not in CLB or Open CLB.
If I would have a W/S during acceleration and wouldn´t pull Speed, the AC would accelerate to 250kts and for that would also descend.
At least I couldn´t find any other info in the manuals

Sorry! But it's the other way around. 120ft ROC is only in CLB or OPCLB and not in SRS. SRS is not an acceleration mode but a fixed speed climb mode. In SRS the FAC modified FD range to give upto 22.5° pitch instead of normal 17.5°. That doesn't happen in CLB/OPCLB.

I found now the reference in the fcom: 1.22.30 P47.
Can you confitm it´s also 120ft/min in CLB or OPCLB?
I couldn't find anything.
Fortunately I'm in the simulator tonight and will check it there.

Hi Vila’s, DSC 22-30-80-20

“GUIDANCEIn SRS mode, the aircraft maintains a speed target equal to V2+10 kt in normal engine configuration. When the FMGS detects an engine failure, the speed target becomes the highest of V2 or current speed, limited by V2+15 kt.

The SRS guidance law also includes:

• Attitude protection to reduce aircraft nose-up effect during takeoff (18 ° or 22.5 ° maximum in case of windshear)
  
• Flight path angle protection that ensures a minimum vertical speed of 120 ft/min
  
• A speed protection limiting the target speed to V2+15 kt.”
  

I just came back from the simulator and we checked it there. In CLB or OPCLB the AC goes into a descend in order to hold the Speed during a Windshear.

Same, well reversed, as OP DES during the driftdown, there used to be a picture showing the residual climb the PERF section.

Indeed, 'always positive' ROC is a key design target behind SRS.

The only confusing thing is why and how vilas got confused, having been correct as ever on the first occasion. :E

​​​​

Alex, golden and FD my apology. I had erroneously mentioned in post 27 that CLB instead of SRS gives 120ft/mt protection. I just repeated that error in the previous post. Indeed it's in SRS and not CLB or OP CLB. As it happens in CLB/OPCLB the mode priority seems to be speed and not climb. So in WS it may even descend. All the more reason to reselect TOGA in windshear to get SRS and more energy, also prevent descent by flying whatever pitch it takes SRS or no SRS.

Hi Vilas,
If you don't mind could you please post the Airbus reply here. Our company has a procedure to modify thrust reduction to 500ft. If windshear is expected the thrust reduction has to be set to 1000ft AAL. Going by your thread, I think even 1000ft AAL won't be a good idea. You could edit out the personal details for maintaining anonymity and then post the reply.

Hello everyone! It’s very strange how Vilas started his explanation in the correct way and made this error in his later posts. I respect him and FlightDetent and in most cases I agree with their posts. By the way :
1.Could someone provide me concrete reference from FCOM/FCTM for TOGA thrust use recommendation/precaution in suspected W/S.
2. There was SB from Airbus about W/S Det. Function and it also covers SRS logic and it states:
”In fact, FMGC orders the SRS mode engagement when:
* At least one of thrust levers is set to TOGA detention and,
-the slats are extended
-main landing gears are not compressed

OR
*At least one thrust of thrust levers is set to MCT/FLX or TOGA and,
- FLEX temp. Inserted in MCDU
-V2 inserted
-slats extended
-the aircraft has been on ground for 30 sec at least

When SRS mode is engaged and if shear conditions stress aircraft’s capability, FMGC progressively adapts pitch orders to the following survival strategy:
1. First, it controls speed to maintain speed target
2. If speed cannot be maintained,it targets +120 ft/min of vertical speed,
3. If vertical speed cannot be maintained,it increases pitch up to 22,5 deg.

Hope it helps:)

sergie
The answer to your para1is in FCTMGENERAL GUIDELINES

• Predictive windshear@ warning (“WINDSHEAR AHEAD" and "GO AROUND WINDSHEAR AHEAD" aural alerts, associated with the W/S AHEAD that appears on the PFDs), reactive windshear warning ("WINDSHEAR WINDSHEAR WINDSHEAR" aural alert, associated with the WINDSHEAR that appears on the PFDs) and windshear detected by the flight crew, request immediate actions.
  
  The following recommendations apply for takeoff after V1 and when airbone (including approach and go around phases):
  
  • The flight crew must set TOGA thrust and should follow SRS orders (if necessary pull the sidestick fully back).
    
    If the FD bars are not displayed, the flight crew should move toward an initial pitch attitude of 17.5 °. Then, if necessary, to prevent a loss in altitude, increase the pitch attitude.
    
  • If the AP is engaged, the flight crew should keep it engaged. The AP disengages if the angle of attack value goes above αPROT
    
  • The flight crew should monitor the flight path, the speed and the speed trend.
    
• Suspected windshear (upon ATC or traffic notification or flight crew observation) and predictive windshear@ caution (“MONITOR RADAR DISPLAY" aural alert, associated with W/S AHEAD that appears on the PFDs) request anticipation of the flight crew to be prepared for a possible windshear
  

Hi Sergei,

Are You referring to the fact that when the predictive windshear procedure migrated from the FCOM to the FCTM the wording and format changed?
In the "old" FCOM PRO-SUP-91 Adverse Weather the use of TOGA as a precaution was specifically mentioned. In the FCTM the use of TOGA is related to the crew and/or PWS detection of the windshear.
Is that what You were thinking about?

Cheers.