alogo:
The answers to most of your questions are in the BEA Final report, with the exception of the mind reading required to understand
why any of the three professional pilots did or didn't do what they did, or didn't, do.
The "why did they do that?" question gets partial answers via estimations made based on what evidence could be collected, as well as what general human factors knowledge has been accrued by the experts in that field.
If you haven't read the final report, I suggest you read it first, and then figure out which remaining questions you have.
It is linked to in various places on this web site in the AF 447 threads, such as
here.
John Tullamarine has provided,
here, a wonderful resource for more reading and information.
So, what is the situation with the AP?
a. As I understood after the ice on pitot tubes melts, speed indicators went
back to normal.
b. Was it possible in that moment to switch on the AP?
c. What is the procedure with AP switching on?
After the accident, and after the unique recovery of the Flight Data Recorder, that information was reconstructed. It appears from the outcome of the flight that neither pilot understood that the airspeed indications had been restored, however, once stalled, that's a moot point until you unstall the aircraft. If you reconnect the AP in a stall ... well, since the Test Pilots aren't required to do that, and thus didn't collect data points on that, the result of that possible action is left open to guess work.
Beyond that, the situation with switching back on the AP is IRRELEVANT.
Pilots are required to be able to hand fly their aircraft in degraded modes. You restore the AP when you are content that you have cleared a malfunction and wish to use its features again. You have to fly the plane.
Was the plane simply falling from the sky, or it had also some horizontal speed?
Yes to both.
If you read the report, you will find that there was a forward vector.
But that doesn't matter all that much after you are stalled.
If you are stalled, your forward velocity simply influences the nature of impact when you crash, unless you make the inputs to recover from the stall and resome flying again. As I and a number of other contributors here have pointed out frequently, being STALLED is NOT FLYING, it is FALLING. Until you aren't stalled anymore, you aren't flying.
As I read the passengers were aware of the plane's loss of altitude?
How do you arrive at that conlcusion? And how does that matter? They were in no position to do anything about that. The pilots were. And didn't effectively take care of it.
RIP, 228 souls.
After the ice from pitot melts (30 sec from AP swiching of, if I remember), all of the cockpit indicators worked normaly and there was absolutely nothing wrong with them?
The reconstruction of the event via the FDR seems to show that, however, as I mentioned above, that is IRRELEVANT if the aircraft is stalled, and the recovery inputs to remedy the stalled situation are not made in a timely fashion. It is also of no help if the pilots don't recognize that the instruments are once again working properly.
That appears to have been part of how this accident came about.
Was there any chance of recovering the plane if pilot increased engine power, or it was already on maximum?
The way to recover from the stall, once stalled, is to decrease angle of attack.
If you aren't yet stalled, and yet are close to a stall, sometimes/often increasing power (and accounting for the pitch up tendency that the increase in power will give you when using underslung engines) will speed you up and thus by the fact of airflow and physics, decrease your Angle of Attack sufficiently to prevent stall.
Once stalled, it is usualy required to lower angle of attack by decreasing pitch, and as the aircraft unstalls and returns to controlled flight, you'd usually use power to recover extra flying speed and restore altitude.
That's a general approach, each situation will have subtle differences. In this case, once stalled, if you go to TOGA, or Max Power, you may increase the pitch up due to the underslung engines, and make your stall recovery more difficult, not less so. Detailed discussion of this has taken place on these forums, and I invite you to head to the link I made up there (which John Tullamarine provided) and use the search tools he suggests.
Why the captain did nothing about stall alarm?
Why indeed? If we only knew.
I mentioned above that mind reading isn't something even the BEA can do in their investigation. None of us can either.
It isn't clear that any of the two, then three, pilots ever clearly identified and stated that "the aircraft is stalled" even though the stall warning was going off at various times during this accident.
My own estimate (guess) is that because there was a known airspeed error issue, at least one of the pilots presumed that a faulty airspeed/pitot system would lead to erroneous stall warning.
I cannot prove that, but it's one plausible explanation.
There are others, to include the belief asserted to be held by some people that an Airbus cannot stall. See the various threads for massive amounts of discussion on that little chestnut.
I can understand that pilots thought that it was false alarm, but when captain entered the cockpit, he had not any knowledge of what has happened. He entered, the pilot told him he has no control of the plane and the stall alarm sounded again. He never said anything about the stall?
Why indeed?
The answer to that remains in the grave.
The Captain was having to catch up to a deteriorating situation. Some of us guess -- and I say GUESS -- that his brief "this is not possible" comment may have referred to an initial diagnosis of "the plane is stalled" and his unwillingness to believe that his two copilots had somehow stalled the plane in the short time since he'd left the cockpit. But he may have been referring to something else, like the incredible rate of descent.
Are the published transcripts full version of what were being comunicated in the cockpit?
Apparently not.
There are ten separate threads on these forums on this topic, and a great deal of discussion on that point. See the link I gave to you for page one of this thread, where John Tullamarine has kindly provided many resource suggestions.
Suggest you PM jcjeant on that particular topic, or Lyman, as they are both quite vocal in their disappointment with the full CVR not being released.
Sorry if I am beeing boring to all of you experts
Not at all.
Read the final report. Ask questions.
There are some folks who can be of help.
