Airbus crash/training flight

[Brakes on]

DS-ATE,
Run out of arguments?
May I suggest you read the last paragraph of my post again? Maybe this will give you a clue on how (part of) the FBW will help the pilot not to overstress the plane.

[DC-ATE]

I've read your last paragraph a few times. It does not tell me why FBW is BETTER than before.

There are those that listen to CNN and those that listen to FOX. Nothing anyone can do will change their minds.

[stickyb]

Originally Posted by lomapaseo

stickyb


Well here I was agreeing with aguadalte and you come in with an authorative sounding statement that doesn't seem to me to match the discussion.

Perhaps there is a misunderstanding among us of the meanings.

Could you precise a little more why/how the aguadalte statement is flawed?

Sorry if I did not make myself clear first time around. The false statement i was trying to counteract is "the computer decides". The computer decides absolutely nothing that its programmer hasn't told it to. Behind every computer program is a human programmer (why does everyone think of Mr Gates?). Too many people think "the computer" can decide things - it doesn't, just regurgitates what the programmer put there. That's where the GIGO syndrome came from (Garbage In, Garbage Out)

The other point about the Big Red Button is that is not a simple task of switching of the automatics, if you did that most modern planes would fall straight out of the sky. The only thing a BRB can do is switch off some of the automatics - the key question will always be which ones do you trust and which ones do you dump.

[flash8]

Too many people think "the computer" can decide things - it doesn't, just regurgitates what the programmer put there. That's where the GIGO syndrome came from (Garbage In, Garbage Out)

With all due respect, and not to be off topic, I don't think many people believe that computers have autonomy of mind. And as for Programming, the fundamentals here are not so much what was intended but what was unintended.

Most critical Software (as far as I know) is formally verified using a methodology such as VDM or Z, as well as isolated n-team n-version programming and polling/voting (or at least it was for the 744 RR EEC). Intended operation is well defined and documented (and probably published somewhere).

Even with n-teams and n-versions in n-languages with n-formal verifications the question is can insidious side effects (for example through multiple system interaction) cause unintended issues through all versions - resulting in a poll and vote for the wrong side?

Of course a faulty initial Specification screws everything up.

Its a few years since my Soft Eng degree so I hope I still make sense.

[lomapaseo]

stickyb

I'm cool now, I suspected it was a fortran language problem between us . Some of you have made a good education out of this for those of us willing to learn. I probably will pick up and use from this some simple-flying explanations when trying to explain this to non-aviation folks.

[belloldtimer]

GMDS Preliminary report

G'day,

You said "as long as the final report is not out" is there a preliminary reprot. I've just seached thru the thread and can't find one, could you post a lnk to it if you have it.

Thanks Steven

[Clandestino]

@belloldtimer:

We were discussing A330 upset, prelim is here:

AO-2008-070: In-flight upset, 154 km west of Learmonth, WA, 7 October 2008, VH-QPA, Airbus A330-303

@Iomapaseo:

Sorry, page break made it look as if it was out of nowhere.

[lomapaseo]

Clandestino

AO-2008-070: In-flight upset, 154 km west of Learmonth, WA, 7 October 2008, VH-QPA, Airbus A330-303

I'm not sure why you posted a link without any explanation

In my view it does not relate to the accident being discussed since this thread should now consider the statement about a surge in power associated with the pitch up.

In my view if there was any direct correlation with the accident in the link, Airbus would have indicated so in their Safety office release.

[Safety Concerns]

this thread has got ridiculous. So

AOA sensors painted over and stuck in one position. A/C stalled and crew performed actions as any crew would do on any aircraft, digital or analogue but it was sadly too late.

Change the bloody boeing v airbus record

[aguadalte]

Dear SC:
I'm quite astonished with the acrimony on your last post.
I thought that you would render some credit to the Safety Concerns name you have chosen to sign your opinions on this forum. Only someone who doesn't have a clue on the importance of the differences of philosophy and design between B & A, may think that it all resumes to a "bloody boeing v airbus record"...

[Safety Concerns]

Dear aguadalte, I think you know I respect your opinion but I feel you have misunderstood mine here.

[belloldtimer]

Can't we all play together

Boys and girls,

Can't we play together. The palyground is big enough for one and all witout fighting about petty things, afterall our primary goal is information to avoid furhter loss of life and liberty isn't it ? Correct me if I'm wrong but the sole purpose of this forum is the dissemination of information to other professionals in the same field.

Yes/No

[CONF iture]

Quote:
Fact is as well, that in at least one Airbus (QF72)

Originally Posted by Clandestino

As long the final report is not out, it is not a fact!!!!!!

Clandestino, do you mean Airbus rushed to publish a RED OEB just for fun ?


Also, as you mention the Malaysian 777 case, and so did others earlier, that incident is very different from the Qantas case :

• The upsets were AP as well as pilot induced.
• In the case of QF72 the airplane was nicely manually flown but the protection did the mess.

Now, to know if one simple (guarded) push button should be installed in the FBW Airbus in order to easily go back to the basic DIRECT LAW ... why not ?
Not a big deal, almost any other airplane fly in DIRECT LAW anyway, do they fall out from the sky ?
To me it would be a very simple way to make sure protections don't play a trick when in doubt ...

Originally Posted by DozyWannabe

The A320 FBW will do *exactly* what the pilot tells it, and stay there as long as it is possible to maintain the attitude commanded

QF72 also demonstrates the Airbus FBW can also do what the pilot never told him to do.

[Safety Concerns]

which is why the A V B argument doesn't belong here.

We would like to know what happened to an A320 and why. I am not interested in egoistical nonsense about man being better than a machine.

As I stated very early on both, in fact all manufacturers build inherently safe aircraft. Please get back to what happened and not what might have happened with superman at the controls.

[Clandestino]

For the n-th time:

From the ATC's viewpoint, flight was proceeding normally untill the radar and radio contact was lost as the aeroplane was returning to land. Maybe I'm mistaken but I believe if some significant fault (and probe or ADIRS fault is significant) during acceptance test flight, flight is cut short and aeroplane is returned to maintenance, untill the time it's pronounced fit for another try. Blocked probes would result in anomalous readings immediately after lift-off, followed by prompt return.

Regarding the Perpignan accident, we're no smarter than we were three days after the crash.

Clandestino, do you mean Airbus rushed to publish a RED OEB just for fun ?

Whatever was written in it, it was published it because Airbus deemed it it necessary. If any aviation-related entity believes that non-acting has serious safety implications, it will act on the basis of high probability and not wait for certainity. OEB's can be withdrawn or ammended.

Now, to know if one simple (guarded) push button should be installed in the FBW Airbus in order to easily go back to the basic DIRECT LAW ... why not ?

Because pilots have their performance and limitations, too. If a pilot is so confused and behind the aeroplane that he allows it to enter protection, then he might start panicking and cut-out the protection that's doing it's job in mistaken belief that it's gone beserk. Mind you: no FBW protected aeroplane, be it Boeing, Airbus, Tupolev or Embraer, has been lost to stall or spiral dive in everyday operation yet. And protections are far easier to implement and more effective if you have FBW than classic controls.

That is not to say that protection makes anyone & his dog able to fly an Airbus. Staying out of protections still demands skill, concentration and foretought. And very seldom something goes seriously wrong and one ends up in altn or direct law and then Airbus needs the pilot at the controls as much as DC-3 needs it.

[aguadalte]

Quote:
Now, to know if one simple (guarded) push button should be installed in the FBW Airbus in order to easily go back to the basic DIRECT LAW ... why not ?
Because pilots have their performance and limitations, too. If a pilot is so confused and behind the aeroplane that he allows it to enter protection, then he might start panicking and cut-out the protection that's doing it's job in mistaken belief that it's gone beserk. Mind you: no FBW protected aeroplane, be it Boeing, Airbus, Tupolev or Embraer, has been lost to stall or spiral dive in everyday operation yet. And protections are far easier to implement and more effective if you have FBW than classic controls.

That is not to say that protection makes anyone & his dog able to fly an Airbus. Staying out of protections still demands skill, concentration and foretought. And very seldom something goes seriously wrong and one ends up in altn or direct law and then Airbus needs the pilot at the controls as much as DC-3 needs it.

That is why:

I suggested a change in the software/logics of the use of the instinctive disconnection push button, located in the side stick, to "bring" the aircraft into a "status" (Alternate Law 1) which would bring the aircraft back to manual, although maintaining a great deal of protections. This would be a pilot friendly status, once he could effectively handle and override aircraft built-in protections in case a serious situation arises. Once the problem was solved, he could return to Normal Law (provided certain conditions met) by switching the Auto Pilot ON.

[Lemurian]

Twenty-one years after the service entry of the first FBW airliner, followed byb the A330, 340, B777, the Falcon X, the A380 and soon the B787 and the A350, we still find advocates of the cables-and-pullies solution.
May I just remind them that cables can break, controls can be mis-set and that happened with dire consequences.
From the B777, there will not be another airliner with mechanical links either to the flight controls or the engines. Live with it or choose another trade.
But in fact, the whole thread is about Airbus-hating, however loud the hypocritical denials are...Going just a bit farther, it's all about not trusting the dastardly conspirative (?) French, sentiment illustrated here :

If (BIG IF) the accident report were to come out showing a fault in the
FBW/computer system on board, does anyone really think that FBW will be
eliminated from this model or any other model aircraft? Of course not. But, then again, I doubt very much the report would indicate that whether it was true or not.

For D-cate in particular, this piece, written by the US-ALPA with the help of NASA could be an eye-opener. Please note that on all these manoeuvres, the Airbus showed a better performance than the Boeing, but for "subjective reasons", the test pilots still prefer the Boeing...Go figure.
At least, they were quite honest about it.

Mind you: no FBW protected aeroplane, be it Boeing, Airbus, Tupolev or Embraer, has been lost to stall or spiral dive in everyday operation yet.

Either I read you wrong or you're wrong : The Gulf Air 320 off the coast of Bahrain and the Armavia IMO qualify for these characteristics.

[Enderby-Browne]

...it was published because Airbus deemed it necessary...

is not the same as "...it was published because Airbus deemed it an important safety issue..."

Much of what Airbus says, does and publishes is for Airbus' sake, first and foremost. Any consequent positive industry-safety repercussions are therefore a side-effect and it would be naïve in the extreme to delude oneself into thinking otherwise.

[fr8tmastr]

I think many are missing the point of FBW as it concerns AB/Boeing. Its not the FBY that's limiting anything, the electric wire just replaces the cable going to the actuator.
The AB/Boeing philosophy differs when it comes to the red button, to disconnect the computer, not the FBW.
I have also read about all the protections AB gives you, like stall over g etc. But nobody has mentioned it also limits roll rate and pitch rate. So say for instance the hypothetical flock of birds is dead ahead. A pilot given enough time might try to sharply turn to avoid. The airbus will turn just fine, but only at a certain roll rate, you want more? too bad. Is that a major concern? heck no, but its there, and that IMO is one of the reasons why the stick and rudder pilots are less happy with the AB FBW compared to the Boeing FBW.

[Clandestino]

Either I read you wrong or you're wrong : The Gulf Air 320 off the coast of Bahrain and the Armavia IMO qualify for these characteristics.

Ermmm.. nope, they don't. In spiral dive aeroplane attains severe nose down attitude either through massive sideslip towards the lower wing or by banking through 90 deg and pitching up (relative to aeroplane's coordinate sys, not ground) - example is Flash air accident. Airbus limits bank to 67 deg, but sidestick has to be out of neutral for banks greater than 33. Pitch is limited to 15 AND and 30 ANU. What Gulf Air and Armavia tought us is that disoriented pilots can stay within the limits and yet drive the fully serviceable aeroplane into water. Now there is food for thought for those who advocate "I-have-full-control" button. And Aquadealte, we we been here before just a couple days ago. Please do read your FCOM and understand it. I have expressed myself imprecisely first time, my apologies, but I do maintain that speed stabilities in altn law with reduced protections are not worthy of being called protections as they can be overriden. Your proposed red button would leave pilot able to overbank aeroplane, attain severe pitch-up or pitch down, stall it or overspeed it. In my book this isn't "maintaining a great deal of protections" at all.