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View Full Version : Siberian A320 Loss of Control Dec 2021


Zeffy
29th Oct 2023, 11:27
Mentour Pilot

punkalouver
29th Oct 2023, 16:09
It seems as if the best thing one can do when unreliable airspeed is encountered is to cover up the airspeed indications. Perhaps easier in some aircraft than others. One should perhaps say to themselves and the other crew that the warnings(such as stall and overspeed) need to be ignored and proper pitch targets are maintained and perhaps in the case of the Airbus.....Our life depends on that BUSS indication. Of course, if AOA vanes are frozen(happened to one of our aircraft) that is a different story.

I suspect that it takes some discipline. Best to think it out once in a while in advance.

Consol
29th Oct 2023, 20:14
Excellent presentation as always by Mentour. Added to AF447 and Air Asia it makes it clear that there are many crews on this planet who can't fly unreliable airspeed, can't realise they are stalling and can't read the FMA. That's why the A350 has unusual attitude recovery mode. That is what we have become.

Liffy 1M
29th Oct 2023, 21:38
Just for accuracy, note that the aircraft was an A321neo, not an A320. https://avherald.com/h?article=4f10cac3

physicus
30th Oct 2023, 06:31
In theory it's really simple in an aircraft with enough power: a hint of unreliable airspeed, fly pitch and power. You have tables in your QRH for the correct settings, and to first approximation this is a memory item (like he says: 80% N1, 10 degrees pitch). Then PNF looks up the actual values to aim for.

TheEdge
30th Oct 2023, 11:15
In theory it's really simple in an aircraft with enough power: a hint of unreliable airspeed, fly pitch and power. You have tables in your QRH for the correct settings, and to first approximation this is a memory item (like he says: 80% N1, 10 degrees pitch). Then PNF looks up the actual values to aim for.

Just to clarify, as per Airbus MEM ITEM, above Thrust Reduction Altitude AND below FL 100, we apply Thrust CLIMB/10 degree pitch (with A/T, A/P and FD off), not 80% N1. The different pitch/trhust N1 % only come after we are in a safe state.

Uplinker
30th Oct 2023, 11:58
Wow. If the facts of this flight are as reported by Mentour then I wonder what has happened to airline pilot training. I have so many questions:

How did this Captain become a Captain ?

Why did they not remove the snow and properly de-ice the airframe ?

Why did they not follow the Airbus memory drill for unreliable speed ?

Why did they sound so panicked on the RT ?

Why did they not set a thrust and an attitude ?

Why did they not transfer control from LHS to RHS correctly ? (why do it anyway?).

Was this their first day flying an Airbus emergency, and their first day flying in icing conditions ? because it seems to have been.

This crew barely got away with it - in part because not having transferred control correctly, both pilots were simultaneously flying and therefore cancelling out most of the inappropriate inputs which allowed the aircraft's built in stability to gradually, slowly, bring them back to controlled flight.

Did this Captain and crew really pass their last recurrent Sim exam, or did something else happen?

FlightDetent
30th Oct 2023, 15:07
Just to clarify, as per Airbus MEM ITEM, above Thrust Reduction Altitude AND below FL 100, we apply Thrust CLIMB/10 degree pitch (with A/T, A/P and FD off), not 80% N1. The different pitch/trhust N1 % only come after we are in a safe state. Caveat: it is quite a bit more complex than that, following what's spelt here will induce further home study and training, in a proper environment.

Uplinker
30th Oct 2023, 15:55
Might have changed, or be different for the Neo, but it used to be:

Below acceleration altitude = set TOGA and 15° pitch up.

Above Acceleration altitude but below FL100 = set CLB thrust and 10° pitch up.

Above FL100 = set CLB thrust and 5° pitch up.

That keeps you flying safely while PM follows and actions the ECAM and STATUS etc.

flash8
17th Nov 2023, 18:13
In theory it's really simple in an aircraft with enough power: a hint of unreliable airspeed, fly pitch and power.
Indeed its amazing how many qualified people forget this, not exactly rocket science, a lot of air transport hull losses could have been avoided if this simple rule were applied!