If it's an error in design, then why did both major western manufacturers implement similar behaviour?

Dozy, please do not beat around the bush. Please quote chapter and verse of the other manufacturer's scheme and which aircraft it applies to. I'd like to be sure we are not comparing apples and tangerines.:}

NB : Emphasis is mine.

The hamster wheel is running again. The speed of 60 kts is irrelevant. NO large airliner be it Boeing or Airbus will be "flying" at 60kts. As Professional Pilots we should know that and NEVER get the aircraft into that configuration airborne. Stop attempting to put blame where it does not belong.

The stall warning was ignored for almost a minute when the "PF", if you can call him that, zoomed and held the aircraft into the stall, well above max altitude. :ugh::ugh:

Do not see any of you Airbus decriers over on the Lion Air thread or the Nightmare liner thread, wonder why that is?:=

OK Dozy. Very good. As we know, Mr. A33Zab knows his stuff.
That shows that the ADIRU design is the source of the conceptual problem.

The same loss of stall warning would apparently occur in a T7 should one somehow be taken to ridiculously high AOA and probably also to the 787.

Let's attempt to discuss why the ADIRU designers determined that it was appropriate to disable AOA at very low airspeeds. Perhaps over on the tech thread.

As we know, at least one aircraft was ill served by this design decision.

I think we all agree the PF was totally unqualified and the second pilot didn't do anything about it and let him do it. The captain came up too late to fix the situation so everybody died. End of story. Kind of sad isn't it? I don't think it would happen on our airline. I'm not saying US airliners are better just saying we wouldn't let a pilot do anything this stupid and not intervene.

To be perfectly honest, at this stage I'm all "discussed out". For now I'm happy to assume that they know something I don't and leave it there.

Iceman50:
There are those of us who are willing to criticize AB but aren't "decriers." Anyway, What is the Nightmare liner thread? I want to read it. :)

Possibly, but probably the error in the static pressure was even greater. I notice in BEA's description of the PEC that the A330-300 (and A340?) does not have the same position error as the -200. Does anyone know where the static ports of the -300 are located?

If the computer disables the stall warning it should inform the pilots that it has done so.

Dearie me.

T7
AMM 34-20-00-019 - ADIRS - ADIRU AIR DATA FUNCTION

5. Corrected Angle of Attack (AOA)

The corrected AOA, from the AOA redundancy management logic is invalid when the CAS is less than 30 knots.

AMM 34-20-00-028 - ADIRS - SAARU AIR DATA FUNCTION

4. Corrected Angle of Attack (AOA)

The corrected AOA, from the AOA redundancy management logic is invalid when the CAS is less than 50 knots.

@ Cool guys:

The FWC (computer) didn't disable the stall warning, if no AOA data is available then the strip value will not be exceeded. (like the T7)


@ HN39:
Same location but some fuselage frames in between.

http://i474.photobucket.com/albums/r...psf5a0e6d5.jpg



@ Dozy & HN39:


http://i474.photobucket.com/albums/r...psfbde316d.jpg

bubbers44
 

bubbers44

It “seems” you do have all the knowledge about flying, stalls, upset recovery, technical aspects from planes etc. etc. However I find it disrespectful how you talk about the crew in this particular flight and indirect your “colleagues”. Try to be positive, we all want to learn and make aviation safer. In my opinion this isn’t the right way.

OK, go ahead and pull full back for several minutes and wonder why the plane quit flying. Don't want to hurt anybody's feelings.

disabled stall warning
 

Nevertheless it was bad luck the captain didnt get his chance to hear steady stall warning when he came into that confused cockpit . The last straw.

.. disrespectful how you talk about the crew ..
 

They don't deserve respect. They didn't follow AF procedures. They caused the stall they didn't know they were in.

They dropped a perfectly flyable plane into the Atlantic.

Disagree - anyone can have a bad day at the office.

Trying to pin it on the crew is just as wrong-headed as trying to pin it on aspects of the aircraft's design in my book. The overall picture shows that the industry as a whole had become complacent when it came to handling stall situations.

100% correct.

You cannot afford 'a bad day at the office' when you're flying an airliner.

Thanks HazelNuts39. I know it's not a simple question, as I'm aware that other manufacturers may have different designs leading to different situation re: SW.
I take for granted what A33Zab said about it (unless someone else challenges his affirmations, with sourced material).


And actually, as CONF iture said, "10000 feet a minute is a good breeze enough for all AoA probes to indicate a pretty similar value."
Thanks A33Zab for the pics, too. :ok:

Now, why struggle to invent some kind of (over-?)complicated fail (un)safe feature for an AF447-like scenario? Solutions seem to exist already, for example combined pitot+AoA vanes on fighters (Rafale comes to my mind) that orient themselves into the wind i.e. continue to measure a "good" value. Perhaps it's more expensive, though?

Good idea. Doesn't the A380 have that combined pitot+AoA vane? It would certainly reduce the pitot pressure error but would not be a total solution because it doesn't change the static pressure error. The pitot by itself does not create negative dynamic pressure at approx. 40 degrees AoA.