Dozy
I've sat on the sidelines watching and reading lately. Your posts were at one time informative and interesting to read, but have turned into total protection of Airbus recently. Airbus doesn't need protection, they are experts at "protections".
I have got to go with gums on this. The computer system, e.g., Alternate Law 1, Alternate Law 2 and subsets of Alternate laws are very confusing. Normal Law and Direct Law are very clear: Normal Law - the computers fly the plane and the pilots watch, Direct Law - the pilots fly the plane and the computers watch. That is simple. The in-betweeners are a mish mash of: You have this but not that except when this is this or that is that....
Think about it, in the case of AF447, they had at most three minutes to determine what was wrong, what was going on and what to do, with the balance of time being on the express elevator to the sea. From a technical and engineering point of view, here is what I see wrong on Airbus' part in this saga:
1. Airbus failed to handle the pitot tube problems in a manner that they should have.
2. Airbus failed in their risk assessment/risk abatement to adequately cover the total waterfront, e.g., total flight envelope. They were nearly mute on flight problems at high altitudes and speeds. Guess they assumed problems couldn't happen there.
3. Airbus failed to provide complete key memorization items in their flight instructions for the A-330, leaving out for the most part, high altitude and high Mach cruise situations.
Now you can say this is Monday morning quarterbacking, but it isn't. It is good common sense, business best practices - risk and risk abatement processes that should have been in place but were not.
You can also say and you have on many occasions, the plane did exactly what it was supposed to do, but in reality, it crashed. That was not Airbus' intent I am sure, nor was it the pilots flying or Air France's intent either.
Like it or not, Airbus has the leading role, it is their airplane (a good one at that), their design, their computer control flight system. Airbus therefore has or should have the leading role in establishing all of the criteria, instructions, do's and don'ts to pass along to individual airlines who buy their planes and then the pilots who will fly them and even train them. Additionally they have the lead role in determining what should be done when critical monitoring/detection devises develop a history of not performing to expected standards or expectations.
Prior to AF447, there was a substantial case history established on the pitot tubes (selected and installed by Airbus) which indicated there was an icing sensitivity problem. A good risk assessment/risk abatement analysis (an industry best practice) would indicate this to be a significant safety item needing rapid attention. Things that happened in flight on other airplanes would be an indicator that sooner or later a flight crew could/would respond incorrectly. As in the role of leader, Airbus must not have/didn't push the issue hard enough with EADS, or so it seems or didn't view correctly the critical nature of pitot icing at high altitude and high Mach.
AF447, three minutes to go (not knowing that at the time), A/P come off, A/T come off, the stall warning sounds, the nose is slightly down and one wing is lower than the other. We are in Alternate, is it 1 or 2? Going too fast? Going too slow? What is the speed? What are the protections? What do we have and what don't we have? What does the memorized list developed by Airbus say? Do we have a memorized list for high altitude/high Mach? That was the situation. Now Airbus did do a good risk analysis/risk abatement for low speed, low altitude situations, landings, T/O's, thus developed the memory lists. But they stopped short. In fact, if you apply the low altitude low speed do's to high altitude/high Mach, it probably makes the problem worse. What happens to THS flight protection in Alternate law? What's the AOA? Confusion? Help? Panic? 3 minutes to sort things out. Cavalry charges, single chimes after single chimes, single chimes every 5 seconds, lots of crickets? Get the gist?
Airbus had the lead on pitot tubes, they selected and installed them, they had the wealth of data regarding icing and what other airline/Airbus aircraft did at cruise when pitots iced. They knew there was a difference between manufacturers and performance/non-performance. What did they do about it? Did they do a risk assessment/risk analysis? Was it deemed to be a hoe-humer or a critical problem when flying at high altitudes and high Mach? What did they advise EADS to do? Airbus has the lead here, not EASA. Did EASA respond appropriately based on Airbus' strong recommendations? Did Airbus have a strong recommendation?
So at cruise in the middle of a moonless night in the middle of the Atlantic Ocean in the active ITCZ at some level of turbulence the A/P quits, and computers go off line, partially but not fully and the plane doesn't even remain in level flight. Now Airbus knew the AOA was a critical key component to assure safe flight, but where was the indicator to know what it was and where it was going? Is there a key memory list, e.g., level wings fly pitch and power? What should be the correct pitch setting when you have no speed indications?
And I could go on in more detail and ask more questions, but I won't. I think there is enough to illustrate that Airbus shares much responsibility as do the flight crew, the airline and even EASA if they relaxed on an Airbus' "Strong" recommendation, if there was one. But Dozy, to continue to protect Airbus is fruitless, it is like pi**ing into the wind, sooner than later you are going to get wet and I think you are getting wet.