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The 787 Dreamliner lifts its nose during taxi run  (Source: Boeing)
Boeing's 787 Dreamliner inches closer to its first flight

Boeing's highly anticipated 787 Dreamliner is more than two years late, but things are finally starting to kick into high gear with the aircraft's development. Over the weekend, Boeing test pilots taxied the jet down the runway at 150 mph and managed to lift its nose off the ground [video].

"Our pilots told me the airplane performed beautifully," said 787 chief project engineer Mike Delaney. "We're going through and analyzing the data to ensure we're ready for first flight. From evaluations we've done so far, everything looks good."

While this may seem like a small step to some, this is just the precursor to the big event which is scheduled for Tuesday. On Tuesday at 10 am PST -- if all goes according to plan -- Boeing's 787 will take to the air for the first time. According to HeraldNet, the composite-bodied aircraft will remain aloft for more than five hours as critical systems and flight performance/handling characteristics are carefully monitored.

3News reports that roughly 600 engineers and 400 mechanics will be on hand for the exhaustive nine-month flight testing phase of the program. During this phase, six aircraft will be flown on a regular basis to work out any problems that are bound to crop up during typical flight testing.

The 787 has been plagued with problems during its prolonged development. Most recently, problems with the aircraft's wingbox were discovered. It was found that composite sheets covering the wings were delaminating under stress.

Many of the problems surrounding the 787, however, have come from the fact that much of the production of key components of the aircraft have been farmed out to different contractors around the world.

Boeing Commercial Airplanes CEO and president Scott Carson noted in early 2008, "The fundamental design and technologies of the 787 remain sound," said Boeing Commercial Airplanes CEO and president Scott Carson. "However, we continue to be challenged by start-up issues in our factory and in our extended global supply-chain."

For those that haven't been keeping up with the program, the 787's airframe is composed of 50 percent composites, 20 percent aluminum, 15 percent titanium, and 10 percent steel. The 787 can cruise at Mach 0.85 and uses 20 percent less fuel than a comparable Airbus A330. For those that like to stay connected while in the air, the 787 also features built-in wired networking.

Boeing has 840 firm orders for its sleek 787 Dreamliner as of November 2009.



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Many of the problems surrounding the 787....
By Amiga500 on 12/14/2009 4:59:27 AM , Rating: -1
quote:
Many of the problems surrounding the 787, however, have come from the fact that much of the production of key components of the aircraft have been farmed out to different contractors around the world.


Thats balls!

Many of the problems are simply due to us not fully understanding composite behaviour in a whole realm of situations*. Infact, the lack of understanding and the cavalier approach to getting them onto aircraft right now is scary.

PR is dictating to engineering how to build the things, and that is not a good situation IMO.

*Boeing have yet to do the ultimate limit load testing on the wing. The aircraft is not certified, and will not carry passengers until that has been achieved.




RE: Many of the problems surrounding the 787....
By axias41 on 12/14/09, Rating: -1
By martinrichards23 on 12/14/2009 6:59:46 AM , Rating: 5
Linking to a google search?

Oh great, point proven!


RE: Many of the problems surrounding the 787....
By axias41 on 12/14/2009 3:48:10 PM , Rating: 2
Did you disprove my statement? 787 original design was flawed, this is a fact. Can you refute that?


By axias41 on 12/14/2009 3:50:40 PM , Rating: 2
Oh, right, I forgot that american designs can't be flawed. They are American!


RE: Many of the problems surrounding the 787....
By invidious on 12/14/2009 10:55:24 AM , Rating: 4
Flight testing is part of the certification process. If you are implying that it is an unsafe design simply because it is not certified yet that would be a poor assessment.

Unless you have information it is not fair to assume that PR is dictating anything to engineering. The only statements you hear are from PR people, not from engineering. I am not familiar with the 787 program but I can assure you FAA certification is not achieved through a lack of understanding.

Certification standards on new aircraft are tougher than ever and must be considered from the ground up. You don't just make an unsafe aircraft and then fix it afterwords to get it certified, it adds years and millions of dollars onto the developement. Boeing has certified enough aircraft to know what they are doing.


RE: Many of the problems surrounding the 787....
By Amiga500 on 12/14/09, Rating: -1
RE: Many of the problems surrounding the 787....
By DougF on 12/14/2009 4:01:48 PM , Rating: 1
quote:
Talk to any stresser and they will moan about the stupidity of putting composites into wing spars (and even worse - ribs) right now. Or fuselages.
They said the same thing when aircraft switched to aluminum...

quote:
In the room I'm in, you'd be doing very well to find even 5% of the engineers would willingly fly on a 787/A350/CSeries within the first 5 years of its introduction.
In the room I'M in, you'd be doing very well to find even 5% of the mechanics would willingly fly on any aircraft...


RE: Many of the problems surrounding the 787....
By Amiga500 on 12/14/2009 4:24:47 PM , Rating: 2
quote:
They said the same thing when aircraft switched to aluminum...


Erm... as opposed to spruce?

I don't think there were many arguments over the move to Aluminium/Duralumin to be honest. Although from what I've read there were numerous manufacturing issues going to stressed skins... is that what you meant?


By DougF on 12/14/2009 5:18:41 PM , Rating: 2
quote:
Although from what I've read there were numerous manufacturing issues going to stressed skins... is that what you meant?
Yes, but maintenance issues as well (ref Aloha Air 243).


RE: Many of the problems surrounding the 787....
By MozeeToby on 12/14/2009 11:19:40 AM , Rating: 2
You make it sound like there is A) No reason to move to a composite airframe and B) No composite airframes flying today. Neither of which are true and besides that there is a reason that flight testing happens before passengers are flown.

A nearly 100% composite airframe reduces weight considerably, saving on fuel costs and indirectly saving on maintenance. It also allows for larger windows and a higher cabin pressure, since composite doesn't suffer from fatigue stress damage as much as aluminum does.

Saying that it isn't certified and trying to assert that therefore the Boeing engineers don't understand the physics and materials science does a discredit to engineering. Do you really think that Boeing would put as much money as they have into this plane without knowing if it would fly without tearing itself apart?

Composites have been used in airframe construction since the 80's. The nearly all composite airframe is the result of more than 30 years of R&D on a wide variety of airframes. It's going to fly just fine.


RE: Many of the problems surrounding the 787....
By Amiga500 on 12/14/09, Rating: -1
By Oregonian2 on 12/14/2009 1:14:38 PM , Rating: 2
Overweight compared to the design target weight or overweight compared to the more conservative alternative?


RE: Many of the problems surrounding the 787....
By Amiga500 on 12/14/09, Rating: -1
By rangerdavid on 12/14/2009 2:29:53 PM , Rating: 2
I'm not starting a flame war, I'm just calling "BS" on you on you for this:

quote:
For the moment, composites are heavier, harder to design, quite unknown in terms of impact tolerance, environmental degradation, lightening strike attenuation, crack propagation...


Please explain this further. Are you suggesting that Boeing used composites solely to reduce the part count for ease of manufacturing? Are you talking about extruded or intruded plastics?

If Boeing says it has used such a high proportion of composite materials in this airframe to reduce weight, what evidence do you have to the contrary (both of some ulterior motive, and (what I consider a very strange assertion) that composites are "heavy" and untested?


By rangerdavid on 12/14/2009 2:22:05 PM , Rating: 2
quote:
Composites have been used in airframe construction since the 80's. The nearly all composite airframe is the result of more than 30 years of R&D on a wide variety of airframes. It's going to fly just fine.


Amen. I was going to post the same comment...

Composites have been seeing use in a variety of modern airframes, many used in the military (where wing load can be quite extreme) and engineers from Boeing, McDonald Douglas, and others have quite a lot of experience with this material.


RE: Many of the problems surrounding the 787....
By Suntan on 12/14/2009 12:33:27 PM , Rating: 2
Enough with your silly "I know more than everyone at Boeing" insinuations and half comments.

You seem to want everyone to think of you as a real smart engineer based on the comments you make, fine then. As one engineer to another, lay out your actual proof to back up what you say or shut yer yapper. Or are you just a guy who took a comm-college course in Pro-E and now you call yourself a "deisgner?"

-Suntan


RE: Many of the problems surrounding the 787....
By Amiga500 on 12/14/09, Rating: 0
RE: Many of the problems surrounding the 787....
By Suntan on 12/14/2009 2:25:17 PM , Rating: 2
quote:
[as you can prob guess, its not Boeing I work for - and Im not going to start listing off design allowables on here]


Pretty much what I thought.

More unfounded blathering with nothing of substance to back it up…

-Suntan


RE: Many of the problems surrounding the 787....
By Amiga500 on 12/14/09, Rating: 0
By Suntan on 12/14/2009 4:32:35 PM , Rating: 2
Now you are throwing out completely wild assumptions about which you know nothing… not very “engineering-like.”

I hope you aren’t prone to doing that at your day job.

…In any case, just more hot air from you with nothing of substance.

-Suntan


By Reclaimer77 on 12/14/2009 1:11:48 PM , Rating: 3
You are an idiot. Please show me your credentials. Because I'm pretty sure Boeing engineers have forgotten more about designing planes than you will ever know.


RE: Many of the problems surrounding the 787....
By DBRfreak on 12/14/2009 1:25:08 PM , Rating: 3
I would be interesting in hearing your credentials as a composite materials engineer. They may be better than mine, but I'm skeptical. You realize that the use of fiberglass panels (yup, those are composites) and other composites goes back for decades?

Also, PR doesn't dictate anything to Engineering, Marketing does - they decide the size, the mission profile and sometimes the subcontracted components (engines, etc.) - but to say that Engineering simply rubber-stamps everything is a bit silly.

As has already been pointed out, FAA, EASA and Transport Canada certification (only ones I'm familiar with) is not a short or simple process. Boeing was talking to the cert. bodies well before the product roll-out. To think that any OEM would develop a new platform without understanding how the ship would be certified is simply naive.

Today, ships are designed specifically around the cert requirements and if something is very questionable, it won't make it on board.


RE: Many of the problems surrounding the 787....
By DougF on 12/14/2009 4:12:00 PM , Rating: 1
quote:
Many of the problems are simply due to us not fully understanding composite behaviour in a whole realm of situations
That may be the cause of some of the problems, but most of the problems are from trying to fit together large structures with clearance tolerances in the thousandths of inches. On any older production line, aircraft were jammed and jimmied together; and if there were two production lines, it was probable that panels/doors/windows could not be swapped between aircraft from different lines. It's gotten a lot better, but trying to get 20-30ft pieces to fit together like a glove when manufactured at separate facilities is still a minor miracle.


By Amiga500 on 12/14/2009 4:21:09 PM , Rating: 1
quote:
That may be the cause of some of the problems, but most of the problems are from trying to fit together large structures with clearance tolerances in the thousandths of inches.


Especially when the components often warp by some quite massive amounts in manufacture.

Hence all the shimming.


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