Video: Cause of Air France Crash

[Admin]

CBS Report on Air France flight number 447: In response to the release of the final report on the crash, Captain Chesley "Sully" Sullenberger comments on the event and what brought the airliner down.

 

 

 

[Gentreau]

Unfortunately that comes across as a bit of a promotion for Boeing at the expense of Airbus, but then it's from an Americam news channel.....

 

Interestingly they completely overlook the fact that under "Normal Law" an Airbus is impossible to stall as the primary and secondary control computers intervene to avoid excessive AoA.

 

It seems that in the case of flight 447 the failure of the pitots put the computers into "Alternate Law" where the computers do not avoid all dangerous conditions, as they don't have enough information. They may even have passed into "Direct Law".

 

It is concievable that a relatively inexperienced pilot could have the mantra fixed in his mind that you can't stall it, so it's OK to pull on the stick if you want to go up, the computers will make it happen.

 

The different "Laws" are explained here: http://en.wikipedia.org/wiki/Flight_control_modes_(electronic)#Normal_law

 

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[Sapphire]

Interesting, but why could they not recover from 10,000 feet when the captain took over the controls? Earlier the stall warning came on and the stick was being held back-even a first solo pilot work that out.

 

 

[Yenn]

Have alook at "QF32" by Richard de Crespigny. He nearly stalled it on landing, but the fact that it was still flying is a good advert for Airbus.

 

 

[Gentreau]

Interesting, but why could they not recover from 10,000 feet when the captain took over the controls? Earlier the stall warning came on and the stick was being held back-even a first solo pilot work that out.

I think it's important to remember that ATPL training is largely based on procedures, systems, teamwork and resource management. The basics of flying are much clearer in the mind of a first solo pilot than in that of a newly frozen ATPL, unless he/she also flys GA at weekends, which is not always the case. Some of those guys and girls are struggling financially to get their qualifications, they probably can't afford to go flying for fun too.

 

The public demand ever cheaper airfares, which leads the airlines to reduce or stop sponsored training. The result is that people in their early 20's have to take on mortgage sized debt to get qualified for a job which pays less and less each year.

 

At some point we (the travelling public) have to stop the madness and accept that you can't fly safely for free.

 

 

[Gnarly Gnu]

Unfortunately that comes across as a bit of a promotion for Boeing at the expense of Airbus, but then it's from an Americam news channel.....

So you disagree with the premise of what they claim - that the linked yoke is more visible to both pilots than an unlinked side-shift?

 

 

[facthunter]

GG there would be arguable advantages either way. The CM1 position over-rides the CM2 . With a linked yoke there is a lot of wasted space and the possibility of being over-ridden by force. ( I don't particularly like the sidestick, but that doesn't matter.) The sidestick is little more than a lever inputting an autopilot with the appropriate microprocessors not allowing an input that would in theory endanger the aircraft. When sensors fail, "normal " indications/warnings are corrupted. Flying a plane affected that way at high altitude, doesn't have a lot of relation to flying a basic 3 axis plane visually. Nev

 

 

[Gnarly Gnu]

Thanks, I am aware that many pilots (including American ones I've spoken to) quite like the feel of the Airbus side shift etc but of course that was not the question I asked Gentreau.

 

 

[Gentreau]

I'm saying that the premise of the article is targeted on that one fact that the sidesticks are not connected, and "it wouldn't have happened in a Boeing".

 

That is only one part of the story. Pilots are trained to fly the type and the sidesticks are part of that type.

 

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[facthunter]

Being aware of the logic of the system is critical. I think both systems are made by Honeywell but that doesn't mean much. Individual airlines may order different "features" some of which may not work well in practice. If you are not endorsed on it ( and I'm not) it would be hard to get specific.

 

As far as "feel" is concerned I think you pressure the sidestick rather than significantly move it. "Feel" in most control systems is artificially generated to prevent over movement at high speed, which would impose excessive structural loads. These planes are a long way away from the basic cable/pushrod type of control. They invariably have differential spoilers as well as ailerons, and hand flying them at cruise altitude is quite demanding. Nev

 

 

[Gnarly Gnu]

What Sully said and demonstrated seems very logical to me so I was just wondering if you were able to refute it, seems not so just a bit of anti-Boeing / anti-American eh. Most Airbus technology is copied from Boeing, this is one of the exceptions and they got it wrong by not linking the controls.

 

 

[Ultralights]

deleted post. nothing of interest, pretty drunk..

 

 

[facthunter]

Sully has made a point that he is entitled to do. I don't accept that I have to refute anything To go deeply into this matter on a forum like this is not appropriate as most of us do not have the specialist knowledge to indulge in serious debate. Also beyond some "interest" factor it has little to do with the aircraft we fly. Trying to apply "conventional flying logic" from our point of view is is not productive beyond a certain point, as we just don't know enough about the way these planes are operated. It is best left to those with current knowledge of the pertinent factors. Nev

 

 

[Gentreau]

I agree Nev, and the same applies to 7 minute TV reports.

 

 

[Gnarly Gnu]

I don't accept that I have to refute anything

Quite right, you don't FH as the question wasn't even directed at you!

 

I was just point out a bit of racism / nationalism that had nothing to do with the A330 flight controls.

 

 

[facthunter]

I did make an assumption there GG as I could see no one else that it was directed to, and I thought it might be rude to ignore it.

 

There is plenty of "rivalry' between Boeing and Airbus Industrie and there has been for a long time. It is a big dollar market and there is only the two of them left. They don't always play fair either.. Nev

 

 

[Gnarly Gnu]

Got that right, Airbus is government subsidised which distorts the market. Pity there isn't at least a third big player but government subsidies kill that opportunity.

 

 

[Gentreau]

Quite right, you don't FH as the question wasn't even directed at you! I was just point out a bit of racism / nationalism that had nothing to do with the A330 flight controls.

Frankly that's a bit strong GG. I request you withdraw your accusation of racism.

 

Post reported.

 

 

[ahlocks]

....Post reported.

Gnu to that corner, Gentreau over there. Now stay there until you've sorted it out (via PM) if you must.

 

 

[facthunter]

Ah, Locks , You're the best. I hope if I ever get banned, you will be the one who does it. Nev

 

 

[Gentreau]

Sorry Ahlocks, but I consider accusations of racism to be offensive.

 

Nationalist, fair enough, but not racist, big difference.

 

All I am tryng to do here is discuss this video in an adult manner, and I find myself accused of being racist.

 

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[Gnarly Gnu]

Well #2 comes over that way Gentreau, denigrating the explanation as unworthy as it was from an 'American news channel'. Is a linked yoke more visible to both pilots than an unlinked side-shift control? Yes or no? Discussing the actual claims of the video was the point, you are free to disagree with it of course but surely you would agree this needs to be on something more substantial than nationality to be adult.

 

 

[Gentreau]

Why should I disregard an accusation that in other circumstances I could make a police complaint about ?

 

Fair enough to have a 'robust conversation' but certain terms are over the mark, and I don't see why I should accept them.

 

I again request Gnarly Gnu to retract the accusation of racism.

 

 

[ahlocks]

Why should I disregard an accusation that in other circumstances I could make a police complaint about ?

The thread is about the cause(s) of the Airfrance crash, not about you and how you see fit to interpret racial vilification legislation Gentreau. Gnu has provided an explanation for his comment and obviously is not going to remove the original.

 

 

[Gentreau]

Off topic - Removed by moderator