Originally Posted by
TTex600
On a related subject, I have been in a 319 that failed to respond to SS input asking for nose down. I was maneuvering, avoiding one buildup and flew into another which was a substantial updraft. I had already pitched for green dot trying to climb above the first buildup and when I flew into the second updraft the aircraft failed to respond to my nose down, fwd, SS input for a couple of seconds. I assumed at the time that the updraft caused a "g" loading that fooled the ELAC. The buildup was small and we flew out of it in a few short seconds.
Originally Posted by
TTex600
Regarding my mentioned experience where a A319 did not respond to a nose down SS input: for the brief moment I was in an updraft, the nose did not follow the input - once I flew out of the updraft the nose came down and we continued as if nothing had happened......... Knowing that pitch is load factor demand, and being in a updraft/downdraft/updraft/downdraft situation, and considering that the nose came down as soon as I passed the building cumulus, and considering that the Bus behaved normally the rest of the flight, I chalked it up to being in an Airbus. To me, it was no different than waiting for the MCDU to finish "updating" the page. Airbus pilots will know what I'm talking about.
Sorry Clandestino, but you're being overly dramatic. No report was made because none was necessary.
I still don't get it. You are trying to jump over towering cumulus by trading as much speed for altitude as possible - "green dot" is very technical term for minimum clean speed. You fail to clear TCU. You hit the updraft and lose downward pitch authority. And yet, you think it is normal aeroplane behaviour.
Congratulations on your coolness but I fail to understand source of it. Why would you think it is normal to loose downward pitch authority? Was it something in your training? Did you experience it many times? Why do you assume that what's valid for navigation system is also valid for flight controls system? Could you please explain how updraft can fool ELAC into robbing you of nosedown authority?
Originally Posted by NARVAL
Maybe this message is not exactly « technical » enough for the Tech log
Not at all, it fits perfectly into this thread.
Originally Posted by NARVAL
They told me that they learnt from that accident a lot of things they certainly did not know at the time.
All of us did. AF447 has gone where no 330 has gone before. Unsurprisingly, there were many surprises to be found there.
Originally Posted by NARVAL
Facts that are well known to test pilots or military fighter pilots, but which you have no way to learn in a career where you start at nearly zero experience on the A320 and end on the A380.
Unless your interest in aviation does not end at what is legally required, that is.
Originally Posted by NARVAL
you move the controls to a position that you think useful…or that the airplane manufacturer recommends
What matters is whether what you do recovers you to normal flight and manufacturers are betting their reputation and existence on their procedures being best available. There was procedure for dealing with unreliable airspeed. There was procedure for approach to stall. None was followed. It would be terrible waste if all we can learn from AF 447 is "Don't pull when faced with stall warning"
For example, when in an unusual position, a stall, a spin, you move the controls to a position that you think useful…or that the airplane manufacturer recommends,and you wait. You wait for long seconds, until the new position of the flight controls gives a result. Then, eventually, you wait some more…Many airline pilots have never practised that, and have no knowledge of it.
I am not surprised at all, since what you wrote is only applicable for spin recovery in some types with less than savoury spin characteristic. If in unusual attitude and not stalled, you do not wait for controls to take effect. They might be mushy or ineffective (EDIT: I should have written "stiff" instead of "ineffective", sorry about the lapsus) but effect will be pretty quick - powered controls lag notwithstanding. Aeroplane that doesn't reply to controls is certain signal of some deeper trouble, be it stall, ice, control failure or airframe failure.
Personally, I am more than little amused by all the exaltations about airline pilots needing full stall recovery training. Ones pleading for it might be correct but let it remain type specific, please. I have just passed 4000 hours mark on aeroplanes that would simply kill me if I ever stall them. Don't see anyone being too excited about it, though.
Originally Posted by NARVAL
forget it, nobody knew anything about it
Is it OK if they just knew the FCOM chapter where they could read about it?
Originally Posted by NARVAL
experts are now considering a pitch-up into the deep stall never encountered in flight testing
Why? Wasn't pitch up flight controls and thrust induced?
Originally Posted by NARVAL
I think that we should keep in mind the very scant knowledge and training of the pilots at the time in the aerodynamics, stall recovery techniques, stall recognition…It was NEVER thought at the time that those planes could fly beyond the « approach to stall ». It was never thought either that the plane could « fly » with 40 degrees AOA and only 8 or 10 degrees of nose up.
So, of course the crew might have done better, but they certainly were not seriously prepared for what happened. May they rest in peace.
Totally agree. Not necessarily for the same reasons.