AF 447 Search to resume (part2)

[Svarin]

What has changed ?

Gibon2,

you are absolutely right.

Did the aircraft change over the years ? Yes and No. No it did not go through any kind of major re-design, and its various versions are quite stable. Yes, some things change in this aircraft, like in any other. What is specific to FBW aircraft is the changing of Flight Controls Computers, through successive software versions. This is done very discreetly. Some mistakes get corrected before they have a chance to do damage. Some are corrected after a fact (or not). But more than that, the very multiplicity of successive versions of such a critically critical piece of software and equipment will introduce a whole new set of potential problems. Specialists call these Byzantine faults, in reference to an ancient war involving traitorous generals. You can add to the can of worms the parallel evolution of other components software versions, like Air Data Computers for example. All these computers and their brand new updated versions do communicate together all the time. Extremely well, usually. Unfortunately, the public will not be educated on this subject by the upcoming inquiry, I would wager.

Of course, such faults as I hint to in the previous paragraph happen very rarely, and that is a blessing. But they do happen, and those who know what they are talking about in IT knew about the potential for it for years, too. Statistically speaking, it would be very difficult to say that such aircraft is inherently safer or more dangerous than this one in the field of modern commercial aviation. However, it is a certainty that Airbus is on the side of "the computers are always right and will have the last word". Boeing would say "the computers are very good, use them, and if you feel like you are better, you are free to give it a try, but dont come back to us crying". A difference in philosophy, not in numerical safety.

Did the pilots change over the years ? Certainly. Nowadays, at some airlines, an instructor or examiner will slap your hand if you choose to fly manually during some parts of a sim check. It is forbidden to touch the manual pitch trim of any Airbus if it is not flying in Direct Law, which never happens in the sim, except for one minute and a half upon initial training so the appropriate box can be ticked. Yes, airline pilots had to go through major rethinking of their role, function, skillset, attitude, etc... It is called "progress". Those who resist this are called "Luddites" or "dinosaurs", regardless of age, by the way.

So, dear Mr Passenger, here was a short answer to your very relevant questions.

Best regards

Svarin

May 26th 2011 at 1205UTC - This post has been edited by parties unknown to me. Profanity was removed. I can accept that. However, Airbus "philosophy sentence" has been modified. I rest my case that a vast majority of professionals -including myself- perceive this particular manufacturer as always trying to deflect blame for an incident or accident from its own design towards so-called "pilot error". This would not be a responsible attitude.