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[QUOTE=Captain_Rightfoot;1000977]Despite the high percentage of Carbon Reinforced Plastic they reckon it passes all the lightening test standards.
I understood the fuselage was a ali fibre/glass resin layer.
5 0r 10 mm ali with fibre glass matting bonded by resin ....is that not so chief?
[quote=lardy;1001053]Look.. I only have info available to the public but I'd be very surprised if they were using fibreglass. It's my understanding that the a380 uses aluminium with fibreglass reinforcement though.Quote:
Originally Posted by Captain_Rightfoot
That's what makes the 787 so special and "new". It has a predominately CRP body and the worlds first (for an airliner) carbon fibre wings. From wiki...
"The 787 features lighter-weight construction. Its materials (by weight) are: 50% composite, 20% aluminum, 15% titanium, 10% steel, 5% other.[79] Composite materials are significantly lighter and stronger than traditional aircraft materials, making the 787 a very light aircraft for its capabilities.[80] The 787 will be 80% composite by volume.[81] Each 787 contains approximately 35 tons of carbon fiber reinforced plastic, made with 23 tons of carbon fiber.[82] Composites are used on fuselage, wings, tail, doors, and interior. Aluminum is used on wing and tail leading edges, titanium used mainly on engines with steel used in various places.[79]"
"Composite fuselage
Disassembled fuselage section of the Boeing 787 Dreamliner
The 787's all-composite fuselage makes it the first composite airliner in production. While the Boeing 777 contains 50% aluminum and 12% composites, the numbers for the new airplane are 15% aluminum, 50% composite (mostly carbon fiber reinforced plastic) and 12% titanium. Each fuselage barrel will be manufactured in one piece, and the barrel sections joined end to end to form the fuselage. This will eliminate the need for about 50,000 fasteners used in conventional airplane building. According to the manufacturer the composite is also stronger, allowing a higher cabin pressure during flight compared to aluminum"
You can read lots about it at [ame="http://en.wikipedia.org/wiki/Boeing_787"] the wikipedia site.[/ame]
Big thanks at DB for the pics :)
This was the criticism of the 747 when it was introduced - but the 747 is the aircraft that made long distance air travel affordable for most people. And the same % figure is true for any aircraft, depending of course on the level of fares you can charge. The cost per seat comes down with increased size almost regardless of anything else. To give an example - simply because of size of aircraft (resulting from amount of traffic) it is cheaper to fly from Sydney to NZ than it is from Sydney to Dubbo.Quote:
Originally Posted by Captain_Rightfoot
John
Last time I flew Brisbane-Winton I could have gone to Singapore for less.Quote:
Originally Posted by JDNSW
Here is an excellent article on pitot icing which may be one of the causes of AF447.
It is looking increasingly as though this aeroplane broke up in flight. There is a good roundup here.
Well... it's been delayed as part of the body side requires reinforcement.
See here.
:(
Actually, as I understand it, it is worse than that - it is the wing attachment. And what is even worse, testing on the actual structure has shown up errors in the structural design. (Software coding errors I wonder?) It is very late in the process to be finding this sort of problem, although obviously better than after it goes into service!Quote:
Originally Posted by Captain_Rightfoot
John
No, the 787 fuselage is almost 100% CFRP. There are Al parts used, but not much - only 20% of the entire aircraft. There's a video somewhere on the net of them making a fuselage section, from start (Carbon Fibre 'yarn') to the finished product.Quote:
Originally Posted by lardy
Here's a pic of a fuselage section prior to removal of the mold:
http://www.voughtaircraft.com/galler...ction1_med.jpg
I think the Airbus A350 will have similar construction, but I could be wrong.
Oh dear. It could be years until we see this thing in the air.Quote:
Originally Posted by JDNSW
The problem of errors in software is, I suspect a sleeping monster in a lot of areas. I ran across one of these in the 1990s, in a piece of navigational software that had been used by one of our contractors for twenty years (with the code lifted from one set of software to new systems without rewriting). Increasing precision of work showed a worrying systematic degradation of data that eventually was traced to a navigational problem. This in turn was eventually found to be a software error that only operated in the southern hemisphere in changing from grid north to true north. The error was that the programmer explicitly changed the sign of a cosine function for negative angles, forgetting that the cosine is negative for negative angles.
More recently, my brother, who is a US resident, advised me of a New York court case where a drink driving case has successfully managed to get the code for a breathalyser to be opened for the court, and has found that there was a simple error in the method of determining an average of readings - instead of summing figures and dividing by the number of figures, the code added each additional figure to the previous sum and divided by two. Which does not give the same answer!
A well documented case was an unmanned space mission, one of the Mars landers, I think it was, where a mission failure was tracked down to an incorrectly handled change of units from imperial to metric.
What I am talking about is errors which do not affect whether the software runs reliably, but gives incorrect results. In most software, testing ensures that no serious errors exist for normal ranges of input, but most software today is so complex that it is impossible to test all possible routes through the software, and there is a real risk that results can be either slightly wrong a lot of the time, or wildly wrong on rare occasions, or both. And they can continue a long time like that.
In very critical systems, such as Airbus fly by wire software, they use triplicated systems, with different hardware, different software teams (not allowed to talk to each other) and different operating systems.
Any reasonable view of the software that is pervasive today in everything we do must come to the conclusion that there are a lot more of this sort of problem lurking to bite us.
John