[paully dub]

Originally posted by Mastrap:
There's an interesting difference between Boeing and Airbus, one that makes me personally prefer flying in Boeing aircraft - in an emergency situation Airbus tends to trust the computer overriding the pilot, Boeing tends to trust the pilot overriding the computer. I know this might sound weird, but I tend to go with Boeing on this one.

Perhaps for a collision avoidance system, the override might make a certain amount of sense.

[PacHead]

Originally posted by Mastrap:
1. The Airbus 380 is by far the most advanced plane in production today. That is not to say that Boeing builds bad planes, far from it, but currently they don't have anything to compete with the 380.
Their current official line 'smaller is better' is a rearguard action which I predict will be changed the second their own super large airline will hit production in about five years from now. By which time the A380 will have been in service for years.

2. The idea of the wing only aircraft was developed in 1920's Germany. So much for being futuristic and innovative.

3. Airbus is NOT a French company, but don't let your ignorance stand in the way of your prejudices. Airbus is a pan European company, with the major stake-holders being located in the UK, France and Germany and now also in the US.

There's an interesting difference between Boeing and Airbus, one that makes me personally prefer flying in Boeing aircraft - in an emergency situation Airbus tends to trust the computer overriding the pilot, Boeing tends to trust the pilot overriding the computer. I know this might sound weird, but I tend to go with Boeing on this one.

1. Advanced in what way ? Among commercial planes ? It is certainly not more advanced compared to various military aircraft. As for larger aircraft, I'm not so sure about that. I remember taking way more 747s back in the day. It seems that most airlines are going for smaller planes now, and certain airports (not huge, major ones of course) in various countries don't even allow 747's to land. Are they going to keep this airbus plane as some sort of luxury airliner like the pictures show or are they going to stuff hundreds of people in there like cattle ?

2. You are thinking about WWII I assume. The "german flying wing" America bomber. They didn't have any jet engines in WWI of course.

3. I know it's not just french, the french need to be picked on a little bit though, because of their evil foreign policies.

I agree with your last paragraph.

[driven]

Originally posted by ambush:




Except when the "pilot" is a terrorist

Are you referring to the Egypt Air plane that took a dive into the Atlantic?

[Disgruntled Head of C-3PO]

Originally posted by PacHead:

3. I know it's not just french, the french need to be picked on a little bit though, because of their evil foreign policies.

Most would say 9/11 was because of America's "evil foreign policies".

Or do you really think they hate you because of your freedom?

[paully dub]

Originally posted by PacHead:

3. I know it's not just french, the french need to be picked on a little bit though, because of their evil foreign policies.

I thought we had a political lounge for that kind of discussion. Oh wait, were you banned from there?

And actually, as I understand it there are more and more long distance routes, as Randman mentioned, and basically connecting Australia and Southeast Asia with the rest of the world. I fly long routes semi often and those big beasts are always full.

[driven]

Originally posted by PacHead:
Also, since none of these planes are finished yet, I'll put my money on the Boeing plane. It looks futuristic. Americans innovate, the french immitate.

What the hell is that thing?
(Is this on Boing's web-site?)

[Mastrap]

Originally posted by PacHead:
1. Advanced in what way ? Among commercial planes ? It is certainly not more advanced compared to various military aircraft. As for larger aircraft, I'm not so sure about that. I remember taking way more 747s back in the day. It seems that most airlines are going for smaller planes now, and certain airports (not huge, major ones of course) in various countries don't even allow 747's to land. Are they going to keep this airbus plane as some sort of luxury airliner like the pictures show or are they going to stuff hundreds of people in there like cattle ?

We are talking civilian airliners. (Although the Eurofighter does give the best of what the US have currently on offer a fair run for it's money.) But that's not the discussion we're having here.
You're wrong about that current commercial realities in the airline industry. All of the major airlines are desperate for larger capacity airliners for their intercontinental routes. The A380 offers a unique opportunity to move larger numbers of passengers while at the same time improving space and comfort in economy class.

2. You are thinking about WWII I assume. The "german flying wing" America bomber. They didn't have any jet engines in WWI of course.

No, read the thread and look at the images posted. I am talking about the 1929 Junkers G38, the first plane ever planned and developed as a wing only plane, albeit without commercial success. This was purely due to the low power output of the engines available at the time, the idea of the wing only aircraft is nothing new and certainly wasn't developed by Boeing.

[PacHead]

Originally posted by Disgruntled Head of C-3PO:
Most would say 9/11 was because of America's "evil foreign policies".

Or do you really think they hate you because of your freedom?

That's a load of crap. It was because 19 degenerate lowlifes decided to sacrifice their worthless, primitive lives to some silly god they worship.

[PacHead]

Originally posted by paully dub:
I thought we had a political lounge for that kind of discussion. Oh wait, were you banned from there?

And actually, as I understand it there are more and more long distance routes, as Randman mentioned, and basically connecting Australia and Southeast Asia with the rest of the world. I fly long routes semi often and those big beasts are always full.

I didn't bring it up.

[Augie50]

Great, the project is already $2,000,000,000 over budget two whole years left before its finished! Gotta love government sponsored mediocrity!!

http://www.reuters.co.uk/newsArticle...k/businessNews

[PacHead]

Originally posted by driven:
What the hell is that thing?
(Is this on Boing's web-site?)

It was on the link from the first post.

[Mastrap]

Originally posted by Augie50:
Great, the project is already $2,000,000,000 over budget two whole years left before its finished! Gotta love government sponsored mediocrity!!

http://www.reuters.co.uk/newsArticle...k/businessNews

Calling the A380 mediocre just highlights your own ignorance. As pointed out before it is easily the most advanced civilian airliner currently in development and production.

Also, Airbus isn't any more 'government sponsored' than Boeing or any other major plane manufacturer.

[itistoday]

[PacHead]

Originally posted by Mastrap:
We are talking civilian airliners. (Although the Eurofighter does give the best of what the US have currently on offer a fair run for it's money.) But that's not the discussion we're having here.
You're wrong about that current commercial realities in the airline industry. All of the major airlines are desperate for larger capacity airliners for their intercontinental routes. The A380 offers a unique opportunity to move larger numbers of passengers while at the same time improving space and comfort in economy class.



No, read the thread and look at the images posted. I am talking about the 1929 Junkers G38, the first plane ever planned and developed as a wing only plane, albeit without commercial success. This was purely due to the low power output of the engines available at the time, the idea of the wing only aircraft is nothing new and certainly wasn't developed by Boeing.

So you're saying the airbus is not going to look all fancy like the pictures, but it will indeed be used to shuttle people like cattle from point a to b. Taking a full 747 with annoying babies crying and kids is bad enough, I'd hate to be on some cattle flight with many more people. You may be right in that it will be a success, time will tell I suppose. It seems as if it's been pretty expensive so far.

I didn't claim Boeing invented the wing aircraft. I was aware of the German one from WW2. I didn't know about the 1929 junkers plane. Interesting.

[FulcrumPilot]

Thanks tooki.

On the blended wing design. It looks cool no doubt. But let me just say that the future for that concept looks pretty bleak. IMHO, I dont think we will see that design come through in the near future. Why? two problems:

1. Pressurization of an non-circular fuselage is a big problem. Because up there at say 35,000 ft the pressure inside will want to make the fuselage circular. So structural integrity is a hurdle for that design.

2. If passengers are going to be placed about 60-80 ft from the central longitudinal axis expect them to spill their drinks everytime the a/c makes course corrections by banking!! You dont feel as much in traditional circular fuselage design because you sit pretty close to that axis.

[Mastrap]

Originally posted by PacHead:
So you're saying the airbus is not going to look all fancy like the pictures, but it will indeed be used to shuttle people like cattle from point a to b.

I suggest looking at some of the sites of the airlines that have ordered the A380. The general consensus appears to be that economy class will get a fair bit more space, which I personally am looking forward to.
A bar for those who wish to stretch their legs will be available in business, with first class seating being as spacious and luxurious as anyone could wish for. Last time I looked Singapore Airlines was experimenting with individual cabins for first class passengers, containing private bathrooms and showers. Which would be incredibly cool.

As per usual, the level of service you'll receive will depend on the money you're prepared to spend on your ticket. I thought that that way of thinking would be in agreement with your own political affiliations.

[Augie50]

Originally posted by Mastrap:


Also, Airbus isn't any more 'government sponsored' than Boeing or any other major plane manufacturer.

Whose ignorant? Let me know when the U.S. has given Boeing billions of dollars to lessen the financial risk of developing new products as European countries do for Airbus. Hell, the only thing Airbus claims the U.S. gov't gives Boeing is money for actual PRODUCT, a rather odd complaint.

http://www.realcities.com/mld/krwashington/10487272.htm

Perhaps you should questions the garbage that comes from your own city's fine newspaper: http://www.thestar.com/NASApp/cs/Con...d=970599119419

[PacHead]

Originally posted by Mastrap:
As per usual, the level of service you'll receive will depend on the money you're prepared to spend on your ticket. I thought that that way of thinking would be in agreement with your own political affiliations.

Oh, no doubt. I'm sure 1st class is awesome on that plane, and so is the pricetag. If somebody has that kind of money then go for it. Me, I'd rather buy 2 G5s or something instead of the price of a 1st class ticket, if I had that sort of disposable cash.

Unfortunately, I'm usually stuck in "economy" class, which should be renamed cattle class. Call it for what it is. I'm tall also, and it doesn't help that some seats are designed for midgets.

[Mastrap]

Originally posted by Augie50:
Whose ignorant? Let me know when the U.S. has given Boeing billions of dollars to lessen the financial risk of developing new products as European countries do for Airbus. Hell, the only thing Airbus claims the U.S. gov't gives Boeing is money for actual PRODUCT, a rather odd complaint.

http://www.realcities.com/mld/krwashington/10487272.htm

I suggest that you read your own article:

the United States alleges $15 billion in illegal EU subsidies to Airbus while the European Union claims $23 billion in unfair U.S. government aid to Boeing

Both the US and the EU governments have been quietly helping their plane manufacturers.


PS: And it's 'who's' as in 'who is', not 'whose'.

Edit: The Star article is a direct reprint of a statement made by Tom Downey, Vice President Communications, Boeing Commercial Airplanes. I am not entirely sure what you're trying to say.

[Mastrap]

Originally posted by PacHead:


Unfortunately, I'm usually stuck in "economy" class, which should be renamed cattle class. Call it for what it is. I'm tall also, and it doesn't help that some seats are designed for midgets.

Same here. I always make sure to be at the airport at least two hours before take off so I can get a seat at the emergency exit. Anything else is just torture.

[Augie50]

Originally posted by Mastrap:
I suggest that you read your own article:

the United States alleges $15 billion in illegal EU subsidies to Airbus while the European Union claims $23 billion in unfair U.S. government aid to Boeing

Both the US and the EU governments have been quietly helping their plane manufacturers.


PS: And it's 'who's' as in 'who is', not 'whose'.

Let's clarify what that "aid" is. In Boeing's case, its the U.S. gov't ordering military equipment from Boeing--the world's largest defense contractor headquartered in the country with the world's largest defense budget. And this is for items like missiles and bombers, things that impact the commercial segment very little.

Aid in Airbus's case is direct money from Eurpean government's to Airbus to develop new commercial products that needn't be repaid unless the product makes enough money to pay back those loans--essentially eliminating much or all of the commercial risk to the company.

[PacHead]

Originally posted by Mastrap:
Same here. I always make sure to be at the airport at least two hours before take off so I can get a seat at the emergency exit. Anything else is just torture.

It's pure discrimination against tall people by the airlines. Somebody should sue 'em.

They'll make all these extra, expensive accomodations for somebody in a wheelchair for example, but who gives a crap about torturing a segment of society that is over 6' ?

[Mastrap]

Originally posted by Augie50:
Let's clarify what that "aid" is. In Boeing's case, its the U.S. gov't ordering military equipment from Boeing--the world's largest defense contractor headquartered in the country with the world's largest defense budget. And this is for items like missiles and bombers, things that impact the commercial segment very little.

Aid in Airbus's case is direct money from Eurpean government's to Airbus to develop new commercial products that needn't be repaid unless the product makes enough money to pay back those loans--essentially eliminating much or all of the commercial risk to the company.

The way I understand it:

Airbus has received technology development loans and grants from the EU. That is standard practice in both the EU and the US. (My own (small) company is currently investigating if we qualify for any of these.)

Boeing, as far as I know, has received guaranteed gov't orders that were made without having been tendered on the open market. That amounts to direct aid.

I am not saying that Airbus is in any way better than Boeing. Both companies are out to pocket whatever help they can get. But calling the A380 a 'government sponsored mediocrity' is a statement you can't possibly back up.

[Thilo Ettelt]

Originally posted by Mastrap:
3. Airbus is NOT a French company, but don't let your ignorance stand in the way of your prejudices. Airbus is a pan European company, with the major stake-holders being located in the UK, France and Germany and now also in the US.

i have to slightly correct you:
"Airbus is jointly owned by EADS (80%) and BAE SYSTEMS (20%)." from here


- Thilo

[chabig]

Originally posted by driven:
But: One of the drawbacks of this airplane is the fact that many airports will have to be retro-fitted to accomodate it. Runways and bridges that the plane will traverse will have to be reenforced to handle the extra weight of this big bertha. New gates will have to be built to accomodate it's size.

Partly right. The airplane is being built to operate at existing airports. To do otherwise would ensure its failure in the marketplace. Airport modifications should be minimal and may be limited to some gate modifications and maybe some taxiway intersections. But that's all.

Chris

[ambush]

Originally posted by Augie50:
Let's clarify what that "aid" is. In Boeing's case, its the U.S. gov't ordering military equipment from Boeing--the world's largest defense contractor headquartered in the country with the world's largest defense budget. And this is for items like missiles and bombers, things that impact the commercial segment very little.

Aid in Airbus's case is direct money from Eurpean government's to Airbus to develop new commercial products that needn't be repaid unless the product makes enough money to pay back those loans--essentially eliminating much or all of the commercial risk to the company.

Bravo. You just VSed interventionism VS and the US' economic policies.

[chabig]

Originally posted by PacHead:
This airbus plane is midget sized compared to the hercules planes the military already uses, so your genius suggestion is not too bright.

No. The Airbus 380 is bigger than anything in the sky.

Chris

[chabig]

Originally posted by Mastrap:
There's an interesting difference between Boeing and Airbus, one that makes me personally prefer flying in Boeing aircraft - in an emergency situation Airbus tends to trust the computer overriding the pilot, Boeing tends to trust the pilot overriding the computer. I know this might sound weird, but I tend to go with Boeing on this one.

I'm not sure what you're referring to. I fly the Airbus 320 and have flown Boeings in the past. I can do everything in the Airbus that I could do in the Boeing except intentionally break it. I have never thought that being able to intentionally break the airplane is a design plus.

Chris

[OreoCookie]

Originally posted by PacHead:
1. Advanced in what way ? Among commercial planes ? It is certainly not more advanced compared to various military aircraft. As for larger aircraft, I'm not so sure about that. I remember taking way more 747s back in the day. It seems that most airlines are going for smaller planes now, and certain airports (not huge, major ones of course) in various countries don't even allow 747's to land. Are they going to keep this airbus plane as some sort of luxury airliner like the pictures show or are they going to stuff hundreds of people in there like cattle ?

2. You are thinking about WWII I assume. The "german flying wing" America bomber. They didn't have any jet engines in WWI of course.

3. I know it's not just french, the french need to be picked on a little bit though, because of their evil foreign policies.

I agree with your last paragraph.

1. No, the A380 doesn't have any stealth technology. The larger 747 (dubbed 747X got canned, AFAIK) got canned, no demand, I guess.

2. You are correct that 1929 is after WW1, but before WW2, hence no jet engines.

3. I don't even need to comment on that, except that I'll be in Paris for New Year. Those evil bastards

[ambush]

pil0t pwn4g3

[Mastrap]

Chris, I am no pilot, but what I have always understood is that there is what could best be called a 'cultural difference' between Airbus and Boeing. Whereas Boeing likes to give final responsibility to the pilot, my understanding has been that Airbus likes to give that responsibility to the computer?

Do you remember when the Airbus went down on take off in New York shortly after 9/11? That, if I remember rightly, was due to the pilot moving the rudder in a way that was beyond the manufacturing specs. The accident happened because the pilot overrode the computer and that brought the plane down. In a Boeing the pilot would not have been able to make the same mistake as all possible rudder movements would have been within the specs.

Please feel free to correct me if I am wrong about any of the above.

[PacHead]

Originally posted by chabig:
No. The Airbus 380 is bigger than anything in the sky.

Chris

We're both wrong it seems. The airbus 380 is bigger than the hercules, but it's smaller than the an 225 cossack. And the airbus isn't exactly "in the sky" yet, since it's not due until 2006.

[driven]

Originally posted by chabig:
Partly right. The airplane is being built to operate at existing airports. To do otherwise would ensure its failure in the marketplace. Airport modifications should be minimal and may be limited to some gate modifications and maybe some taxiway intersections. But that's all.

Chris

Please cite references. I'd love to be corrected (seriously), but I've read numerous articles that state the contrary.

[driven]

Originally posted by Mastrap:
Chris, I am no pilot, but what I have always understood is that there is what could best be called a 'cultural difference' between Airbus and Boeing. Whereas Boeing likes to give final responsibility to the pilot, my understanding has been that Airbus likes to give that responsibility to the computer?

Do you remember when the Airbus went down on take off in New York shortly after 9/11? That, if I remember rightly, was due to the pilot moving the rudder in a way that was beyond the manufacturing specs. The accident happened because the pilot overrode the computer and that brought the plane down. In a Boeing the pilot would not have been able to make the same mistake as all possible rudder movements would have been within the specs.

Please feel free to correct me if I am wrong about any of the above.

Didn't a terrorist group claim responsibility for that action?

[Mastrap]

Originally posted by driven:
Didn't a terrorist group claim responsibility for that action?

No. It was a very unfortunate pilot error in a difficult cross wind situation, no terrorist action involved.

[Mastrap]

Originally posted by driven:
Please cite references. I'd love to be corrected (seriously), but I've read numerous articles that state the contrary.

The only issue I know about is that some airports need to strengthen their runways because of the high impact weight of the Airbus. Everything else should fit just fine.

PS: Interestingly enough, the Discovery Channel is just now running a programme about the Airbus and the Boeing.

[chabig]

Originally posted by Mastrap:
Chris, I am no pilot, but what I have always understood is that there is what could best be called a 'cultural difference' between Airbus and Boeing. Whereas Boeing likes to give final responsibility to the pilot, my understanding has been that Airbus likes to give that responsibility to the computer?

Do you remember when the Airbus went down on take off in New York shortly after 9/11? That, if I remember rightly, was due to the pilot moving the rudder in a way that was beyond the manufacturing specs. The accident happened because the pilot overrode the computer and that brought the plane down. In a Boeing the pilot would not have been able to make the same mistake as all possible rudder movements would have been within the specs.

Please feel free to correct me if I am wrong about any of the above.

Mastrap,

I appreciate the opportunity to talk about different design philosophies.

The philosophical difference in Airbus' fly-by-wire design versus Boeing's is that the Airbus system enforces hard limits, so that the pilot cannot fly the airplane outside of its safe operational envelope. Boeing, when they designed the 777, decided to implement a system with a soft limit, so the pilot can fly to the limit, but then override the limit if desired. Let me stress that by overriding the limit you are taking the airplane into unsafe territory which may even include the in-flight breakup of the airframe due to over-stress.

The merits of each system are forever being debated. Generally, I think it's safe to say that older pilots, with no experience in fly-by-wire airplanes are opposed to hard limits because they don't appreciate the benefits. Younger pilots, and those with experience in fly-by-wire airplanes appreciate the control and protection afforded by hard limits. Airplane manufacturers build airplanes for customers. When Boeing built the 777, their first fly-by-wire transport, it was the customers who asked for the soft limit system. It was those same customers who asked for a yoke between the legs rather than a side-stick controller. This, in my opinion was a mistake, but remember that it was the old guys who made that decision. Now the 777 is 10 years old, and those pilots have retired. I think it's safe to say that Boeing will never build another transport airplane with a yoke. All new airplanes will have side-sticks because the benefits are so enormous.

Historically, there are few instances where a pilot "saved" the airplane by over-stressing it. And there are large advantages to designing in the the hard limits, since it is known in advance how the airplane will be flown. In the USAF, I flew both the F-16 and the F-15. The F-16 has a hard G limit, which cannot be overridden. The F-15 requires continual care by the pilot not to exceed G limits. It's safe to say that more F-15s were destroyed by over-G than F-16s. And when it was needed, the F-16 could be G'd up quicker than the F-15 because all you had to do was pull the stick to the stop and let the flight control system give you the G as fast as it could. In the F-15 you had to approach the limit with care so as not to overshoot.

So let's just say there are advantages and disadvantages to both approaches.

By the way, the A300 loss was due to pilot misapplication of rudder, plain and simple, not control philosophy. Generally, rudder inputs aren't processed by the computer, except that the magnitude of the rudder movement is limited as a function of airspeed. That same pilot in a Boeing airplane would have broken the vertical tail off too. All transport airplanes are built to the same certification requirements. The certification requirements are predicated on expected pilot control inputs. Unfortunately, the requirements didn't anticipate the grossly inappropriate rudder input made by that pilot.

Chris

[FulcrumPilot]

Originally posted by Mastrap:

Do you remember when the Airbus went down on take off in New York shortly after 9/11? That, if I remember rightly, was due to the pilot moving the rudder in a way that was beyond the manufacturing specs. The accident happened because the pilot overrode the computer and that brought the plane down. In a Boeing the pilot would not have been able to make the same mistake as all possible rudder movements would have been within the specs.

Please feel free to correct me if I am wrong about any of the above.

American 587 was an A300 and the flight controls on those are not digitally controlled, so I think you got it all wrong on that one. I don't think it even had the FADEC on it.

[TETENAL]

Why did the pilot do a grossly inadequate rudder input?

[chabig]

Originally posted by PacHead:
We're both wrong it seems. The airbus 380 is bigger than the hercules, but it's smaller than the an 225 cossack. And the airbus isn't exactly "in the sky" yet, since it's not due until 2006.

You're right. The AN225 is bigger, both in size and weight. It has a max takeoff weight of 600,000 Kg versus the A380s max takeoff weight of 590,000 Kg.

Chris

[Mastrap]

To Chris and Fulcrum:

What safeguards do exist on a plane to let the pilot know that his/her actions are putting the plane at risk, like in the instance of the A300 in NYC? And shouldn't these mistakes been overridden by a monitoring system?

[chabig]

Originally posted by TETENAL:
Why did the pilot do a grossly inadequate rudder input?

That's the million dollar question. It was done in response to a wake turbulence encounter. But why? Probably due to improper training. I believe American was training their pilots to use rudder to try to roll the airplane.

[TETENAL]

Originally posted by chabig:
That's the million dollar question. It was done in response to a wake turbulence encounter. But why? Probably due to improper training. I believe American was training their pilots to use rudder to try to roll the airplane.

What is a "wake turbulence"? And why must you roll the airplane?

Was it improper training or was the plane designed disregarding psychological limitations of a pilot?

[chabig]

Originally posted by driven:
Please cite references. I'd love to be corrected (seriously), but I've read numerous articles that state the contrary.

I'm working on it. Here is a reference that states the weight per wheel on the A380 is less than the weight per wheel of the 747. It's the weight on each wheel that really matters where surface weight bearing capacity is being discussed.

http://www.pbs.org/kcet/chasingthesun/planes/a380.html

Here is another reference that talks about the A380 is terms of size but points out that weight is not a problem:

http://oregonstate.edu/instruct/hsts421/doel/onA380.htm

This one talks specifically about accommodations being made at Paris' Charles de Gaulle airport. Again, size, not weight is the issue:

http://64.233.161.104/search?q=cache...ications&hl=en

Finally, here's pretty good paper about the new larger aircraft:

http://www.ifalpa.org/Interpilot/2004/NLA.pdf

Chris

[chabig]

Originally posted by Mastrap:
To Chris and Fulcrum:

What safeguards do exist on a plane to let the pilot know that his/her actions are putting the plane at risk, like in the instance of the A300 in NYC? And shouldn't these mistakes been overridden by a monitoring system?

In the case of improper rudder use, there is what is known as a rudder limiter. This limits the achievable rudder deflection at high speed. But it's designed to meet the certification requirements, which again, didn't anticipate the type of rapid, rudder reversals used by the American pilot. The rudder limiter is supposed to provide some (limited) protection from inadvertent rudder inputs, not total protection from gross inappropriate rudder inputs.

Chris

[chabig]

Originally posted by TETENAL:
What is a "wake turbulence"? And why must you roll the airplane?

Was it improper training or was the plane designed disregarding psychological limitations of a pilot?

Wake turbulence is the disruption of airflow that is left behind after an airplane flies through a piece of sky. It's similar to the wake that a boat leaves behind it. But behind an airplane the wake turbulence is three dimensional and includes a strong rolling component. So an airplane encountering the wake turbulence behind another airplane may experience a strong rolling upset. To counter that roll, you would attempt to roll in the opposite direction. Roll is primarily accomplished with lateral stick or yoke inputs. Rudder primarily controls yaw, and secondarily-roll, in certain circumstances. The American pilot tried to use rudder to control roll, and his inputs resulted in structural failure of the vertical tail.

Chris

[FulcrumPilot]

Originally posted by chabig:
That's the million dollar question. It was done in response to a wake turbulence encounter. But why? Probably due to improper training. I believe American was training their pilots to use rudder to try to roll the airplane.

Must have been some crazy **** turbulence. Check this reconstuction out.
It is easy to blame it on pilot error but these guys go through pretty serious training I would like to believe. Also I'm pretty sure the airbus engineers would have tested extreme rudder stresses, so I'm perplexed how it could just rip off due to excessive rudder inputs. Must have been some mofo of a wake turbulence.


http://www.ntsb.gov/events/2001/AA58...path_web01.wmv

[TETENAL]

It sounds like a design mistake to me. Pilot input should never allow a structural failure. Also a plain should be able to withstand these wake turbulences since they can be sort of expected.

[chabig]

Originally posted by FulcrumPilot:
Must have been some crazy **** turbulence. Check this reconstuction out.
It is easy to blame it on pilot error but these guys go through pretty serious training I would like to believe. Also I'm pretty sure the airbus engineers would have tested extreme rudder stresses, so I'm perplexed how it could just rip off due to excessive rudder inputs. Must have been some mofo of a wake turbulence.


http://www.ntsb.gov/events/2001/AA58...path_web01.wmv

I have some knowledge of what American's training was like, and they emphasize the use of rudder to control roll. This training was out of line with accepted industry practices and when the litigation is over I predict that American will take the brunt of the blame.

As for rudder stresses, I will repeat that vertical tail surfaces are not designed to withstand the type of stress placed on them by this pilot's inappropriate input. It's that simple. The plane can handle full rudder. It can handle moving the rudder from one side to the other. It cannot handle repeated, rapid, rudder reversals. Another way to view this is that jet transports have been around for about 50 years. They've all been designed to the same basic certification standards. And to my knowledge, no pilot has ever applied the type of rudder reversals this pilot did. Had he done nothing with the rudder the airplane would have been OK.

It wasn't the wake turbulence that destroyed the airplane. It was the pilot's response to the turbulence that destroyed the airplane. Still, in our industry, airplanes of the future are built upon the lessons learned and lives lost in the past. It's probably safe to say that future airplanes will be designed with this mishap in mind.

Chris

[chabig]

Great video, by the way. The red lines on the rudder indication show how the rudder limiter shrinks the allowable rudder deflection as airspeed increases. Still, not how many times he stepped on full left, full right rudder...that was the improper and unnecessary control input. Airplanes just aren't built to take that.

Chris