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If this was a simple loss of pitots due to icing, the aircraft should not have crashed... others (with same flight control & air data architecture) have been through similar rare occurences of it but landed safely. There has to be something else at play.

For several years now, Airbus has offered its customers a special safety program - called "BUSS" -- at a cost of €300,000 per aircraft. If the airspeed indicator fails, this software shows pilots the angle at which they must point the plane. It is a retrofit option for A320/A330/A340 aircraft, but it has been a standard fit on the A330/A380 aircraft, likewise the automatic TCAS functions are supposed to standard on the new aircraft, and a retrofit option for existing aircraft. The simple reason that it is not required equipment is that it is not a certification requirement.

ALL pilots are taught how to fly with unreliable airspeed (fly pitch/power)...in order to even use BUSS, you have to realize that you have unreliable airspeed, which means the crew should have gone to pitch/power anyway. Airbus themselves doesn't recommend the use of BUSS at the altitude that AF447 was at.

Moreover, the airframe has 3 independent air data computers, as well as the standby instruments. The information from the three angle of attack vanes is fed into the three air data computers, before being calculated into information presented on the PFD. If one has a loss of air data on one of the three independent systems, the pilots will replace the faulty air data with the spare.

To get to a situation where you have no air data available, you need to have the loss of all three air data computers, as well as the standby airspeed indicator and altimeter, and certification authorities see that is a very rare event.

Air data is nice to have, but it is not essential, pilots can still fly and aircraft based upon attitude and thrust, loss of air data alone should not cause a crash.

It boils down to: "Would pilots even use BUSS if it was available?"

Non-pilots would almost always answer "Yes"... For some (current and former) pilots, it would be a "No" (and one's a former Airbus a test pilot, but he'd probably still use it if he's line flying and the procedure calls for it).

Another thing about BUSS is, it's not something that you should rush into... You go there when you get NAV ADR Disagree, i.e., when the aircraft cannot determine if it has 1 correct vs 2 wrong, or 2 correct vs 1 wrong, due to the discrimination logic), and after you determine that you (as a human) cannot determine which one is correct and which one is wrong, or ALL is wrong... then, you take a leap of faith by disassociating flying with air data, by going to inertial data only... ie: switch all ADR to off.

Simulator refresher scenarios entail total blockage of all pitot tubes (according to Airbus this is "very unrealistic") just when reaching acceleration height after take off at night over water.

This will cause the same (false) speed indication on all indicators. Plus, as you have just lowered pitch to accelerate and retract flaps, one can miss the unusually quick rate of speed increase (because of the blockage, indicated speed will increase with altitude even if you are not accelerating the aircraft).

As all speed indications have the same error, none is rejected by the computers and the high speed protection will eventually engage, pitching significantly up to reduce speed (you cannot override this pitch up).

Switching all 3 ADR (Air Data Reference) to OFF will force reversion to direct law (thus canceling all speed protections) and you can revert to basic pitch & power flight. If installed, you will also see the BUSS (basically an AoA indication) activated.

However AF447 was at cruise flight level, not at low altitude, where the center of gravity will be very far aft as per system design (fuel distribution into elevator trim tank). Any aircraft with far aft CG at high altitude is very, very tricky to control manually!

Now here are some of my personal thoughts about possible AF447 scenarios:

one of 3 cockpit crew members is in rest compartment as is normal for cruise flight, leaving 2 pilots on the flight deck
CG is far aft as is normal for cruise flight -crew is looking for a suitable area of weakest weather radar reflections to penetrate ITC
St.Elmo's fire is further degrading communication with ATC via HF
slowly icing blocks all pitot tubes (without change in ambient conditions, [i.e. temperature, wind speed/direction, altitude] this is not easy to realize)
turbulence and emerging into much warmer air near the significant huge area of convective weather upsets this tricky situation and causes either the low or high speed protection to significantly change pitch and trajectory...
Suddenly the crew are faced with an airplane upset in speed, pitch and roll in (quite possibly) severe turbulence and surrounded by strong convective weather!
Quite easily engines will also flame out under these extreme conditions, leaving you to control speed only through pitch.

They seem to have tried to cancel the speed protection as indicated by the PRIM and SEC FCC going off line (ACARS messages received show they were switched off and did not trip off).

They could have successfully done this by switching all 3 ADR to OFF, but they would then have had to fly the aircraft with far aft CG in direct law at high altitude and in strong turbulence...

Speculations however will not solve this accident, but as anyone can see this is not a simple right or wrong, good or bad pilot/airplane thing at all. I am certain the fellows in the front office tried till the very last second to safe all souls aboard and their ship.