Boeing 787 Dreamliner Represents Composites Revolution

www.designnews.com ^ | June 4, 2007 | Doug Smock

[RockinRight]

Well, less than 5’10 I am, but I’m well over 110 pounds! I find that if someone is next to me, that my entire lower region is sore, cramped, and uncomfortable for hours after flying.

[Abathar]

Thank you very much, that did answer all my questions on the repair of the composite structures vs their aluminum counterparts. Being able to bolt on patches during their heavy maintenance schedule looks like that will be a lot easier than what they do now, I also found the lightning strike info very interesting. I know how much work it is to replace cracked aluminum support frames, if they can reduce that as much as they say that alone will save so much time in hanger repair time that the cost per mile will drop considerably. They are expensive and all new, but I would fly on this bird any day now.

[r9etb]

Well, less than 5’10 I am, but I’m well over 110 pounds! I find that if someone is next to me, that my entire lower region is sore, cramped, and uncomfortable for hours after flying.

OOOooooooohhhhh, you must be a very discrete and yet remarkable person to be able to perform like that for hours on a plane..... ;-)

[RockinRight]

Um...not for that reason. More because my legs are smashed together diagonally and my manhood flattened between them for hours.

[Moonman62]

Something else I came across is that the 787 will have a gust compensation system for the vertical and horizontal planes. The 777 only has one for the horizontal plane. That should make for a very smooth ride.

[RJL]

Well, there are several 380's flying

I thought it was only a couple, can you point me to information showing "several" A380's flying?

[diogenes ghost]

It appears as though there are 7 or 8 flying so far, not sure how up-to-date the lists I saw are.

I did see a photo of a 3 ship formation.

Google "A380 production list" for those that are flying, A380 photos" for the pics.

[steveyp]

Clearly a triumph of European Engineering and Ingenuity.

Viva La France and all that.

[Thermalseeker]

That is another question, repairing the carbon fiber vs. aluminum skin. Since it is baked and essentially one big solid piece lets say some moron runs the forks of a forklift through the body of the plane, what is the repair cost and structural integrity afterwords compared to just replacing and re-riveting the aluminum skin of aircraft now?

Not a problem. Although carbon is a bit harder to work with than fiberglass, it isn't hard to repair at all. As a material, it's harder to work with, mostly because it's hard on tools such as drills and cutting implements. It also conducts, so static can be an issue.

One problem with carbon is when it is bent to the point of failure, it very often fails almost explosively. If, for incidence, you take a carbon tube, such as a windsurfer mast, and bend it to the point of breaking, it doesn't just snap like a twig. It explodes and delaminates. The result is very often not repairable. OTOH, if you punch a hole in a carbon sheet, such as a wing section or fuselage side, it's easy to repair.

[Abathar]

Thanks - I own a tool and die shop so fixing metal I know all about, but I have never worked with carbon fiber before.

[Thermalseeker]

Since the composites are inherently non-conductive, lightning damage prevention systems are incorporated into them... i.e. They run wire in the matrix during the fabrication process

Not all composites are nonconductive. Carbon is conductive.

Not sure about what Boeing is doing with the 787, but embedding conductive wire mesh is in the structual laminate to dissapate static charge is common practice in several composite homebuilts I'm aware of. Most notably, the Lancair, has been using this technique for about 10 years after some rather catastrophic failures after lighting strikes in flight.

[Thermalseeker]

Thanks - I own a tool and die shop so fixing metal I know all about, but I have never worked with carbon fiber before.

No problem. Although I'm an electrical engineer by trade, my partner and I do composite sailplane repair and refinish nowadays. I also built a composite Europa XS touring plane, completed last year. I don't have the mesh in my Europa and I'm very careful about flying near convective weather.

Composites, and in particular epoxy/carbon or epoxy/fiberglass, are great materials to work with.