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A320 stall recovery

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A320 stall recovery

Old 6th Apr 2021, 08:16
  #21 (permalink)  
 
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@ Vilas

Maybe I misunderstand your post, but if you do stall recovery in a simulator, you must remember what you experience might not represent what the aircraft would do in real life, as the "stall" data for the sim is not available. You just "fly" a computer, and this computer does not have the actual stall behaviour of the real aircraft.

From a Airbus testpilot, I have the following : "both A321 and A330 have nice stall characteristics. If deeply stalled, it requires a very distinct nosedown for quite some time, so not to enter a second stall"
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Old 6th Apr 2021, 10:28
  #22 (permalink)  
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What you say is not true anymore. Airbus has provided authentic data package to Sim manufacturers and what the sim behaviour in a stall is very authentic and not merely a computer idiosyncrasy. Except it cannot create any g loading.
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Old 6th Apr 2021, 11:14
  #23 (permalink)  
 
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Yes, further to what Vilas is saying is the UPRT training which all pilots will start to get over the next couple of years. UPRT Training on non Extended Envelope Training sims should have ceased by now as it's negative transfer of training.

Last edited by compressor stall; 7th Apr 2021 at 12:48. Reason: Added "UPRT" to remove ambiguity
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Old 6th Apr 2021, 12:08
  #24 (permalink)  
 
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OK Vilas, then I stand corrected. I have always appreciated your in depth knowledge of the Airbus

2 years ago, this was not available. When have Airbus started to provide these authentic data packages ?

What do you ask the sim center about, if you want to check if they have this installed ? is it Extended Envelope Training sim ?
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Old 6th Apr 2021, 12:14
  #25 (permalink)  
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Within EASAland there is no regulatory requirement to update sims with full stall/post stall data for UPRT approval

FAA, there is
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Old 6th Apr 2021, 13:16
  #26 (permalink)  
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compressor stall

Within EASA, details on FFS approved UPRT capabilities can be found on the Qualification Certificate section "J Additional Capabilities".

This Qualification Certificate must be displayed near to the FSTD by regulation. You can also view these certificates on the EASA website.
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Old 6th Apr 2021, 15:16
  #27 (permalink)  
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ZFTWhat's the situation on CAE std 2.0 about deep stall? I didn't bother to check.
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Old 6th Apr 2021, 19:06
  #28 (permalink)  
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vilas
My only direct Std 2 full stall experience in an appropriately qualified FFS is with an L3H device.

​​
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Old 7th Apr 2021, 10:04
  #29 (permalink)  
 
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With FBW failures we must remember to fly Airbus FBW like a B737. Go back to basics:

Look at primary flight display - pitch and bank and speed.
Pitch/power couple - actively control the pitch.
The vertical speed readout is your performance.

Things like this that we never normally do should be practised a lot in the SIM, which hopefully will be coming in soon. Flying skills and reactions will only be fully maintained with actual physical practise. Even if the SIM dynamics are not quite correct, it is useful to see the instrumentation readouts, and practise one's raw data scan and coordination of the controls without the full FBW assisting.
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Old 7th Apr 2021, 10:27
  #30 (permalink)  
 
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Done this in an fully certified for UPRT A320 NEO Sim:

As a stall is only dependent of AoA first and most important thing is to lower pitch. Well below the horizon. Then roll wings level, check speed brakes retracted, because these reduce your critical AoA. Thereafter deploy FLPAS 1, as they significantly increase your AoA crit. If you see a good positive speed trend add a little bit power and when slats are half way out and speed is above Vls start releasing the forward stick input to smoothly let the nose rise. If terrain is no factor, altitude loss is secondary. It will be approximately 4000'.
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Old 7th Apr 2021, 11:09
  #31 (permalink)  
 
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Are you sure ?

The last SIM stalling I remember before Covid was A330 and I am pretty sure we kept well within 1,000'. Obviously we knew it was coming, so we were prepared. Don't lower the nose too much.
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Old 7th Apr 2021, 12:06
  #32 (permalink)  
 
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Just like AF447...

Height loss is secondary. Getting out of the stall is all about lowering the angle of attack.

Last edited by compressor stall; 7th Apr 2021 at 12:45.
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Old 7th Apr 2021, 16:13
  #33 (permalink)  
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LW20

When you pitch well below the horizon and add thrust to recover the flight path you need to change the attitude quiet a bit it either triggers a secondary stall or VFE exceedance.
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Old 11th Apr 2021, 06:41
  #34 (permalink)  
 
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During the initial recovery you have to keep the thrust at idle to avoid a pitch up force created through the engines. You wait with your recovery until you are above Vls. Then you start smoothly pitching up again and later smoothly adding some thrust. You will come close to VFE, but not above. During the "procedure" thrust will not exceed the numbers for straight and level flight.
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Old 11th Apr 2021, 17:01
  #35 (permalink)  
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Airbus recommended procedure is to add thrust once stall warning has stopped and wings are level.
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Old 12th Apr 2021, 07:51
  #36 (permalink)  
 
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This is true according to the memory Items: adding thrust comes before path recovery.
From my experience in the sim I think I instinctively pitch up first and add thrust gently after or maybe at the same time to avoid the pitch up moment like LW20 mentionned above.

Last edited by pineteam; 12th Apr 2021 at 08:18. Reason: Added one sentence
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Old 12th Apr 2021, 15:27
  #37 (permalink)  
 
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The "practice stall and recovery' that we teach in the Simulator will definitely be different from a stall that one may encounter on line. But an easy method to teach it is as follows:
1) Do not use the Bird as it is unreliable in a dynamic situation.
2) When entering the stall condition tell the trainee not to apply any backpressure on the sidestick till the speed reaches VLS. Then enough backpressure to maintain V/S 0.
3) When aircraft stalls tell the Trainee to just take hands off the stick. The nose will drop. Once the nose drops the PF asks for Flaps 1.
4) The nose will drop to the extent that the 'black box' on the PFD will just reach below the horizon line and it will pitch up again. If it pitches up you will get a secondary stall. So the idea is to hold enough forward pressure to prevent the 'black box' rising again (i.e. hold it just below the horizon).
5) The PM has only moved the Flap Lever to F 1. But it will take a while for the Slats to extend. The PF can glance at the Upper ECAM and once the Slats are fully extended raise the nose smoothly to get a V/S of 0 on the PFD (No need to open thrust)
6) Once the V/S reaches 0 on the PFD open enough power to kill the 'trend arrow'

The trick in preventing a secondary stall is:
a) Do NOT allow the box to pitch up once it comes below the horizon.
b) Wait for the Slat to fully extend on the Upper ECAM
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