If you cannot meet the rules, change them
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While this does paint the FAA as a bunch of cowboys, there are (as always) unstated/unanswered questions that may indicate this action isn't unreasonable.
- What are the EASA standards for this subject - are they more or less stringent than what the FAA a) currently imposes, and b) what they intend to regress to?
- The statement "To this day, we have not had one manufacturer that has been able to demonstrate compliance with that rule" is made. That surprised me, until I saw that even the A380 was certified before this rule came into force - given that a fair amount of the A380 is made (like the Dreamliner) of composites, the two probably aren't that far apart in terms of lightning protection
Ka?l wrote:
Planes made of aluminum are Faraday cages and are very safe against lightning, when planes made of composite materials are not. When a lightning strikes a carbon-made section, it makes a hole in it.
Composite parts have been flying for a long time. Can you really make that statement with 100% confidence? Are you a materials/aeronautical engineer?
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
Stuart Dootson wrote:
given that a fair amount of the A380 is made (like the Dreamliner) of composites, the two probably aren't that far apart in terms of lightning protection
These planes are very different. A380[^] is mostly made of aluminum when the B787[^] is mostly made of composite.
Stuart Dootson wrote:
Composite parts have been flying for a long time.
We are not talking about models or fighter jets with a high attrition ratio but of commercial jets. We are not talking about small parts but about entire jets.
Stuart Dootson wrote:
Can you really make that statement with 100% confidence?
Yes.
Stuart Dootson wrote:
Are you a materials/aeronautical engineer?
I'm an engineer with a background in mechanics, materials and structure calculations - I am not the only one to claim these planes are less safe: Weldon, a 46-year veteran of Boeing and a pioneer in aerospace design, talks about major safety problems affecting the brand new Boeing 787 Dreamliner. [...] Weldon believes it will be very difficult for Boeing to make the 787 as safe as an aluminum plane and he adds that Boeing management repeatedly ignored his concerns and those of his colleagues about the plane's design.[^]
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
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Ka?l wrote:
. Building such planes using massively composite materials is an argument for commercials, it is not an engineer choice.
Bullshit, Karl. You are no expert here, and are, as usual, talking out your ass. [edit] carbon-composite is the material of choice for modern aircraft construction because it has a much higher strength to weight ratio than any other material available, and resists damage from corrosion and fatigue much longer than any metal [/edit]
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Stuart Dootson wrote:
given that a fair amount of the A380 is made (like the Dreamliner) of composites, the two probably aren't that far apart in terms of lightning protection
These planes are very different. A380[^] is mostly made of aluminum when the B787[^] is mostly made of composite.
Stuart Dootson wrote:
Composite parts have been flying for a long time.
We are not talking about models or fighter jets with a high attrition ratio but of commercial jets. We are not talking about small parts but about entire jets.
Stuart Dootson wrote:
Can you really make that statement with 100% confidence?
Yes.
Stuart Dootson wrote:
Are you a materials/aeronautical engineer?
I'm an engineer with a background in mechanics, materials and structure calculations - I am not the only one to claim these planes are less safe: Weldon, a 46-year veteran of Boeing and a pioneer in aerospace design, talks about major safety problems affecting the brand new Boeing 787 Dreamliner. [...] Weldon believes it will be very difficult for Boeing to make the 787 as safe as an aluminum plane and he adds that Boeing management repeatedly ignored his concerns and those of his colleagues about the plane's design.[^]
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
KaЯl wrote:
I'm an engineer with a background in mechanics, materials and structure calculations
Similar to most mechanical and structural engineers - still doesn't qualify them to speak authoritatively about the specifics of that subject.
KaЯl wrote:
Weldon, a 46-year veteran of Boeing and a pioneer in aerospace design
Who, according to various sources never worked on composites. Way to stay up with the state of the art. Oh, and he might just have an axe to grind, given he was fired from Boeing for "threatening the life of a supervisor". Still, we wouldn't want to let anything get in the way of a good conspiracy theory, would we.
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
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Ka?l wrote:
Building such planes using massively composite materials is an argument for commercials, it is not an engineer choice
It is absolutely an engineering choice - the weight advantage is very significant, which improves fuel burn significantly.
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
Stuart Dootson wrote:
the weight advantage is very significant
This advantage will disappear when you will have to add all the extras to compensate for all the lost properties of metal-based designs.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
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Cite your source. I believe you are speculating from utter ignorance here.
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Good.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
As I thought. You have no source to cite, and are indeed just sharing your usual ignorance of the facts with us.
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KaЯl wrote:
I'm an engineer with a background in mechanics, materials and structure calculations
Similar to most mechanical and structural engineers - still doesn't qualify them to speak authoritatively about the specifics of that subject.
KaЯl wrote:
Weldon, a 46-year veteran of Boeing and a pioneer in aerospace design
Who, according to various sources never worked on composites. Way to stay up with the state of the art. Oh, and he might just have an axe to grind, given he was fired from Boeing for "threatening the life of a supervisor". Still, we wouldn't want to let anything get in the way of a good conspiracy theory, would we.
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
I don't see any moral hazard here on the part of the aircraft companies, either. If they were to allow lightning susceptible aircraft onto the market, they would lose their business after the first lightning related disaster. There would be no logic behind producing an aircraft that is vulnerable to a lightning strike, not even for short-term profit motives. Doesn't make any sense - it's not like they could divest themselves from such a problem and just ignore it. It would threaten their existence. I also think it is a problem that has already been solved through the incorporation of laminated aluminum mesh. No conspiracy here that I see.
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I think it would, and because of the use of a composite material, the total weight of aluminum mesh + composite would still be less than that of solid aluminum construction. Grounding could easily be done by fixing electrical equipment at designated grounding points on the mesh. It is a process that is already used on military aircraft - I believe they laminate the mesh onto the composite.
73Zeppelin wrote:
because of the use of a composite material, the total weight of aluminum mesh + composite would still be less than that of solid aluminum construction
Good luck with the metallic meshing when you'll have to do some maintenance after a lightning strike.
73Zeppelin wrote:
. Grounding could easily be done by fixing electrical equipment at designated grounding points on the mesh
There is way to much current to use the metallic meshing - It would not be able to dissipate the power, and it would be good for the carbon around. There's around 1MW of electricity produced in today's aircrafts, and it's growing.
73Zeppelin wrote:
I believe they laminate the mesh onto the composite.
It can be also coated on the surface. New technologies are also develop to 'chemically' depose a metallic layer on top of the carbon panel.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
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As I thought. You have no source to cite, and are indeed just sharing your usual ignorance of the facts with us.
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I would like to see the design of the future A350 first. Nowadays everything is driven by marketing. Building such planes using massively composite materials is an argument for commercials, it is not an engineer choice.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
Ka?l wrote:
composite materials is an argument for commercials, it is not an engineer choice.
Bollocks. Fibre composites are extraordinary (and BTW I was a mechanical engineer before I decided to waste my life in computers). While dural is damn tough, you just cant beat FRPs.
Morality is indistinguishable from social proscription
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While this does paint the FAA as a bunch of cowboys, there are (as always) unstated/unanswered questions that may indicate this action isn't unreasonable.
- What are the EASA standards for this subject - are they more or less stringent than what the FAA a) currently imposes, and b) what they intend to regress to?
- The statement "To this day, we have not had one manufacturer that has been able to demonstrate compliance with that rule" is made. That surprised me, until I saw that even the A380 was certified before this rule came into force - given that a fair amount of the A380 is made (like the Dreamliner) of composites, the two probably aren't that far apart in terms of lightning protection
Ka?l wrote:
Planes made of aluminum are Faraday cages and are very safe against lightning, when planes made of composite materials are not. When a lightning strikes a carbon-made section, it makes a hole in it.
Composite parts have been flying for a long time. Can you really make that statement with 100% confidence? Are you a materials/aeronautical engineer?
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
Just a side note --- the B-2 bomber is an all-composite (I believe) aircraft. To date, AFAIK, there have been no lightning tragedies regarding this aircraft. And it has been flying for a number of years.
AF Pilot
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73Zeppelin wrote:
because of the use of a composite material, the total weight of aluminum mesh + composite would still be less than that of solid aluminum construction
Good luck with the metallic meshing when you'll have to do some maintenance after a lightning strike.
73Zeppelin wrote:
. Grounding could easily be done by fixing electrical equipment at designated grounding points on the mesh
There is way to much current to use the metallic meshing - It would not be able to dissipate the power, and it would be good for the carbon around. There's around 1MW of electricity produced in today's aircrafts, and it's growing.
73Zeppelin wrote:
I believe they laminate the mesh onto the composite.
It can be also coated on the surface. New technologies are also develop to 'chemically' depose a metallic layer on top of the carbon panel.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
I think the problem has already been solved. 1. http://www.compositesworld.com/articles/lightning-strike-protection-for-composite-structures.aspx[^] 2. http://www.newscientist.com/article/mg18625061.600-striking-planes.html[^] 3. http://www.youngeagles.org/questions/afmviewfaq.asp?faqid=566[^]
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KaЯl wrote:
I'm an engineer with a background in mechanics, materials and structure calculations
Similar to most mechanical and structural engineers - still doesn't qualify them to speak authoritatively about the specifics of that subject.
KaЯl wrote:
Weldon, a 46-year veteran of Boeing and a pioneer in aerospace design
Who, according to various sources never worked on composites. Way to stay up with the state of the art. Oh, and he might just have an axe to grind, given he was fired from Boeing for "threatening the life of a supervisor". Still, we wouldn't want to let anything get in the way of a good conspiracy theory, would we.
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
Stuart Dootson wrote:
still doesn't qualify them to speak authoritatively about the specifics of that subject.
Please, what are your qualifications?
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
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Just a side note --- the B-2 bomber is an all-composite (I believe) aircraft. To date, AFAIK, there have been no lightning tragedies regarding this aircraft. And it has been flying for a number of years.
AF Pilot
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Ka?l wrote:
composite materials is an argument for commercials, it is not an engineer choice.
Bollocks. Fibre composites are extraordinary (and BTW I was a mechanical engineer before I decided to waste my life in computers). While dural is damn tough, you just cant beat FRPs.
Morality is indistinguishable from social proscription
fat_boy wrote:
Fibre composites are extraordinary
Who said they are not? They are just suited yet to build entirely a commercial aircraft, they are way too many problems not faced to make a safe design for now. I'm not claiming that their mechanical properties are not interesting, even if one could raise question about the studies related to fatigue - for instance how can you preemptively detect micro-cracks in carbon? I say that carbon based materials are not ready to replace aluminum in commercial flights because some other aspects (electrical, thermal, maintenance) are not prospected enough.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
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Thanks for your comment, it add a lot to the talk as usual. Now please take your pills.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
Ka?l wrote:
it add a lot to the talk as usual
It certainly did. Rob answered the single-most important question that would have occurred to anyone after your rant.
Jon Smith & Wesson: The original point and click interface Algoraphobia: An exaggerated fear of the outside world rooted in the belief that one might spontaneously combust due to global warming.
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Stuart Dootson wrote:
the weight advantage is very significant
This advantage will disappear when you will have to add all the extras to compensate for all the lost properties of metal-based designs.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
Ka?l wrote:
This advantage will disappear when you will have to add all the extras to compensate for all the lost properties of metal-based designs
All these stupid American designers. So easy for you to show them up.
Jon Smith & Wesson: The original point and click interface Algoraphobia: An exaggerated fear of the outside world rooted in the belief that one might spontaneously combust due to global warming.
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Don't forget to tale the blue one.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
Ka?l wrote:
Don't forget to tale the blue one.
Just like Heinze. You had a dream and when you woke up you needed to share your new 'reality.'
Jon Smith & Wesson: The original point and click interface Algoraphobia: An exaggerated fear of the outside world rooted in the belief that one might spontaneously combust due to global warming.
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fat_boy wrote:
Fibre composites are extraordinary
Who said they are not? They are just suited yet to build entirely a commercial aircraft, they are way too many problems not faced to make a safe design for now. I'm not claiming that their mechanical properties are not interesting, even if one could raise question about the studies related to fatigue - for instance how can you preemptively detect micro-cracks in carbon? I say that carbon based materials are not ready to replace aluminum in commercial flights because some other aspects (electrical, thermal, maintenance) are not prospected enough.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
Ka?l wrote:
I say that carbon based materials are not ready to replace aluminum in commercial flights because some other aspects (electrical, thermal, maintenance) are not prospected enough.
That's ridiculous. They're used in military grade aircraft.
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73Zeppelin wrote:
because of the use of a composite material, the total weight of aluminum mesh + composite would still be less than that of solid aluminum construction
Good luck with the metallic meshing when you'll have to do some maintenance after a lightning strike.
73Zeppelin wrote:
. Grounding could easily be done by fixing electrical equipment at designated grounding points on the mesh
There is way to much current to use the metallic meshing - It would not be able to dissipate the power, and it would be good for the carbon around. There's around 1MW of electricity produced in today's aircrafts, and it's growing.
73Zeppelin wrote:
I believe they laminate the mesh onto the composite.
It can be also coated on the surface. New technologies are also develop to 'chemically' depose a metallic layer on top of the carbon panel.
The law, in its majestic equality, forbids rich and poor alike to sleep under bridges, to beg in the streets, and to steal their bread Fold with us! ¤ flickr
Provide a site where these declarations can be checked - or a book - anything. . .I guess you can't.
Jon Smith & Wesson: The original point and click interface Algoraphobia: An exaggerated fear of the outside world rooted in the belief that one might spontaneously combust due to global warming.
