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Engineers on the project say wing design flaw will prevent test flight in 2009

Boeing's 787 “Dreamliner” has been more of a nightmare for many at Boeing as the project has cost significantly more than expected and is still two-years late (and counting).

Another problem in the 787's design has been found, this time in the wings. During tests to certify the aircraft, damage to the wings and wing box of the 787 was found. The damage was delamination of the composite sheets covering the wings under stress.

The Seattle Times reports that the structural flaw in the Dreamliner was discovered in May during ground tests that bent the wings upwards to simulate stress during flight. The stress at the end of rods used to stiffen the upper wing skin panels caused the composite plastic material used in the wings to delaminate.

The damage to the wing occurred just beyond the Dreamliner's load limit, described as the maximum weight the wing is expected to bear in service. The Seattle Times mistakenly reported last week that the damage occurred just over the wing's ultimate load, which is 50% higher than the in-service limit load the wing is expected to endure. The limit load is the FAA test target and proves that the problem with the design of the wing is worse than originally believed.

The plane could have flown after the wing damage, but the test flights would reportedly have been severely restricted. The damage the wing sustained is reportedly not severe enough to have caused any sort of catastrophic failure had it happened in flight.

The design flaw and time needed to devise and implement repairs on the fleet means that the test flight will not likely happen this year according to one engineer on the project. The test flight was delayed in late 2008 to Q2 2009.

The damage to the wings extends inside the fuselage of the aircraft as well making repairs more difficult. The failure in the wing and the wing box is not the fault of Fuji Heavy Industries, who manufactures the components for Boeing. That means Boeing is solely responsible for any cost overruns and time delays because of the issue.

The fix has yet to be certified but could involve engineers creating a U-shape cutout in the end of the upper wing skin stringer and then refastening the reshaped stringer ends with new titanium fittings.



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Confused...?
By Amiga500 on 7/31/2009 11:17:30 AM , Rating: 2
Is this not old news?

News that the wing failed long before ultimate limit load was reported weeks ago on flightglobal.

http://www.flightglobal.com/blogs/flightblogger/20...

Tellingly the fact that Boeing were not willing to fly the thing at all for flight testing reveals how poor the wing performed. Ultimate limit load is the equivalent of 4.5g and limit load the equivalent of 3g, far beyond what normal airliners experience... even in virtually all the test flights.

A 2g turn is heavy, unheard of in 99.9999% of flights, and extremely easy for test pilots to avoid. That is 67% of limit load. Yet boeing were unwilling to let the plane get into the air to learn vast amounts about the control systems etc and also take the heat off. Says it all really.

The problem is bigger than they let on.

Anyhow. They've decided on how to fix it... allegedly.

http://www.flightglobal.com/articles/2009/07/23/33...




RE: Confused...?
By Gyres01 on 7/31/09, Rating: -1
RE: Confused...?
By Jedi2155 on 7/31/2009 11:33:55 AM , Rating: 5
It seems like everyone is calling them idiots, but no one really seems to care that this is a completely new plane with lots of design challenges. With a body made composed primarily of composite materials, I would think the design challenges are probably complex and more difficult to fix than many of the people lambasting them.

In either case, mistakes were made and some heads should be rolling.


RE: Confused...?
By bdot on 7/31/2009 11:43:50 AM , Rating: 5
All DT commenters are Aeronautical Engineers Duh..


RE: Confused...?
By Mclendo06 on 7/31/2009 10:33:56 PM , Rating: 1
yep...


RE: Confused...?
By 91TTZ on 8/2/2009 3:38:31 AM , Rating: 3
No, we're just critics. There's a difference. We're not offering to help fix the problem, we're only blasting Boeing for not doing it right.


RE: Confused...?
By MozeeToby on 7/31/2009 11:49:34 AM , Rating: 3
If you were in the industry, you'd understand. For 2 years we heard nothing but how amazing and revolutionary the airplane was. How their partnerships with other companies were going to make delays a thing of the past. How the airplane would literally change the way airlines do business.

Now, they've just got 3/4 of the industry pissed off at them because everyone has a hand in this plane. The company I work for, for instance, will eventually have $1.5 million in revenue for each dreamliner that leaves the factory. While waiting for the 787 to fly, we've had to lay off people.

In other words, there's a lot of frustration, both because of the lost income as well as the fact that they didn't deliver like they said they were going to. I'm not saying it's fair, like you said, a new plane is a hugely complex piece of machinery, the dreamliner in particular.


RE: Confused...?
By brybir on 7/31/2009 3:07:22 PM , Rating: 3
Seems like if you are in the industry you would know that long delays were and are a real possibility. Happens quite a bit, most notably on the defense side when dealing with new tech.

Perhaps your company should ask Boeing to front some cash. If your contribution is important enough, and the delays at Boeing threaten your ongoing operations, I am guessing they will prop you up to avoid causing any more problems. Then again, if your entire company was depending on one plane and it being executed properly I would say that is just a bad business decision or one that was not planned out well.


RE: Confused...?
By Einy0 on 7/31/2009 6:54:39 PM , Rating: 2
I think you are misplacing your frustrations on people being laid off. We are in a Global recession people are getting laid off everywhere. Things are turning around, but it will take time. You should be happy Boeing is proceeding carefully. What if they sold lemons instead? I suppose your company could cancel it's orders and buy some Airbus planes. Then again Airbus planes have had a tendency to just fall out of the sky as of late...


RE: Confused...?
By bjacobson on 7/31/2009 12:21:39 PM , Rating: 2
Even with all the design hurdles to overcome, this is one heck of a plane. 20% fuel savings over the 767...


RE: Confused...?
By BZDTemp on 7/31/2009 4:50:53 PM , Rating: 5
1. Lets see that come to life - so far it is just computer predictions.

2. Advancement in engine tech is likely to account for big savings. Maybe even more than the optimized weight and aerodynamics.

The A380 uses less fuel that the current 747's so of course Boeing should be able to make the Dreamliner use less than a 767 - after tech has moved a long nicely these last years.


RE: Confused...?
By knutjb on 8/1/09, Rating: -1
RE: Confused...?
By Amiga500 on 8/1/2009 7:33:06 AM , Rating: 1
quote:
Even with all the design hurdles to overcome, this is one heck of a plane. 20% fuel savings over the 767...


You might be interested to know that if a propfan engine were used, fuel savings would be 50% over a 767!

(and that is from the 1980s NASA propfan tests... wait and see how the updated tests perform)


RE: Confused...?
By knutjb on 8/2/2009 4:26:52 AM , Rating: 1
I was too noisy in that application. Some of the blade tech made it's way into turbo props. Turning at lower speeds on turbo props, the noise difference wasn't an issue. I haven't seen if they have revisited it. It was prettycool looking.


RE: Confused...?
By ikkeman2 on 8/7/2009 2:00:20 AM , Rating: 2
and a cessna citation uses even less fuel, while going only a few hundred instead of a few thousand miles at only a few hundred instead of almost a thousand miles an hour...

- what's your point.


RE: Confused...?
By Masospaghetti on 8/7/2009 10:02:33 AM , Rating: 2
There are other very significant issues with using a propfan - and while ultimate efficiency is better, noise is an issue and so is safety -- I wouldn't want to be in that plane when you have a prop blade separation.

To give you an idea of how much energy these blades would have if they separated, a traditional turbofan with a kevlar-reinforced cowl sometimes cannot contain a separated turbine blade - there have been instances where the blade has literally severed the entire fuselage of the plane in half and wedged into the other engine. Now imagine what would happen if there was no cowl at all...

Personally I would love to see more competing technologies for engines, everything uses turbofans now and its kind of boring - bring back the supercharged 28-cylinder Wasp Major radial!!


RE: Confused...?
By sxr7171 on 7/31/2009 7:39:02 PM , Rating: 3
Wasn't that what all the new-fangled computer simulation was supposed to be for? Anyway, certainly people are being way too harsh, but insiders at Boeing say the problem started with the proclamation by the CEO that "Boeing is no longer an engineering company". So what are they now? A marketing, logistics and outsourcing company that orders parts engineered by everyone but themselves to put together somewhere?

It's a real sad scene how we've made real engineering so "unglamorous" and actually boast that we don't do any real engineering. Just let them do it Japan, Taiwan, China and India. Maybe people would be inclined to do a Ph.D in engineering if companies thought about getting some quality in-house engineering talent for a change.


RE: Confused...?
By knutjb on 8/1/2009 5:22:21 AM , Rating: 2
If you want to sell to most markets those countries need to have a part of production to keep them sold on buying your product over someone else.

quote:
It's a real sad scene how we've made real engineering so "unglamorous"

So you and who are taking credit for the "unglamorous" part? Just curious...


RE: Confused...?
By ikkeman2 on 8/7/2009 2:03:05 AM , Rating: 2
that should only be true for military stuff- but you're right. Ab builds 320's in china for a reason, and japan/italy invested heavily in the 787 for a reason.

ofcourse Engineering is still Glamorous - have a look at my xls sheets and be awestruck!


RE: Confused...?
By Sazar on 8/3/2009 11:23:11 AM , Rating: 2
Not to mention that like the 777, this plane was designed completely on computer/paper and not modeled like older planes, even through the A340 era Airbus aircraft.

Seeing the variety of issues with both the big-kahuna Airbus and now Boeing, it is clear that looking for better, longer range, more fuel efficient, more miles per passenger at lower cost is indeed taking it's toll and not so easy to implement.

The upside is, we will have more fuel-efficient aircraft that can travel further and provide greater comfort :)


RE: Confused...?
By Samus on 7/31/2009 11:50:10 AM , Rating: 3
quote:
Boeing design idiots should spend some time in France......Billions down the drain is becoming the new American way.....


You've got to be fucking kidding...Boing aircraft have a FAR superior flight record compared to Airbus, AND Boing is substantially better at keeping to design and delivery schedules. The A370 has been delayed for YEARS, and now all the sudden everybody is throwing a fit over a 12-18 month delay to the TEST flight?

These are AIRCRAFT and they must have a 0.00001% chance of failure in every single component. LET THEM GET IT RIGHT. Especially because nobody is losing money except for them. It's not like your tax dollars have anything to do with the Boing engineering program. Go complain about NASA somewhere, you know, something we all have at least some insignificant investment in.


RE: Confused...?
By BrgMx5 on 7/31/09, Rating: 0
RE: Confused...?
By ClownPuncher on 7/31/2009 1:45:50 PM , Rating: 5
Boeing receives "public funds" for defense contracts, NASA projects, and a number of other government contracts. The public isn't paying for commercial airliners in the United States.


RE: Confused...?
By Jeffk464 on 7/31/2009 2:15:39 PM , Rating: 1
I'm not so sure about that one. I think boeing tends to rip the government off to help the bottom line. That being said, the 747 also had a lot of problem when it was in this stage and I would say that it was definitely a success.


RE: Confused...?
By PandaBear on 7/31/2009 2:24:42 PM , Rating: 2
So does every single aerospace company toward its own government. Every one of them are semi-nationalized industry due to the national security, foreign trade, and the shear size of the industry. There is no way to get politics and public funds 100% out of it.


RE: Confused...?
By BrgMx5 on 8/1/2009 6:45:14 PM , Rating: 2
Oh yes it is.

Advanced programs funded by the military will produce tech that will eventualy be integrated in comercial products.

And i'm not saying it is wrong, just saying that it is not that black and white


RE: Confused...?
By PandaBear on 7/31/2009 2:22:35 PM , Rating: 2
But they also bring in a lot of foreign revenue. Do you want them to burn some tax dollar while generating a lot of foreign sales (hence tax dollar)? or do you want to abandon Boeing and start buying all planes from Airbus?


RE: Confused...?
By homebredcorgi on 7/31/2009 3:33:36 PM , Rating: 2
Boeing receives funds from the US government from direct military contracts (commercial and military funds can't mix - they are literally separate companies), indirect research through NASA or academic universities and tax breaks.

Airbus on the other hand received a multi-billion dollar non-recourse loan to build the A380. Non-recourse means that if they can't pay up, the European governments are stuck with the bill, not Airbus. Boeing on the other hand used their own money (and that of some of the major suppliers) to develop the 787. If Boeing's 787 is truly screwed and never flies, there is a very good chance the company would go bankrupt (and probably be purchased by another defense contractor). So yes, they both receive public funds, but not exactly in the same way. If the Europeans hadn't been giving out free money to develop commercial transports, I would say both companies are about even in terms of subsidies...but that is not the case.


RE: Confused...?
By rippleyaliens on 7/31/09, Rating: -1
RE: Confused...?
By MrBlastman on 7/31/2009 12:58:47 PM , Rating: 2
I was with you until you started bashing the geeks. What's wrong with being a nerd or a geek? By even being at this site there is a high likelihood that you are part geek yourself...


RE: Confused...?
By rippleyaliens on 7/31/09, Rating: -1
RE: Confused...?
By BrgMx5 on 7/31/2009 1:23:34 PM , Rating: 5
FYI

Planes crash mainly due to improper maintenance and human error (usually poor decisions in the face of unusual circumstances).

Design flaws are not that usual, and it is perfectly natural that the development of aircraft that push the envelope, like the airbus A380 due to size, the Concorde due to its speed or the 787 due to the use of composites will be delayed as tests and assembly reveal trouble spots in something that wasn´t tried before.

Now to your bullsh*t comment, Airbus might be European and Boeing American, but the amount of American and European subcontractors that work for them makes you look like an idiot


RE: Confused...?
By MrPoletski on 8/4/2009 6:37:20 AM , Rating: 2
quote:
but the amount of American and European subcontractors that work for them makes you look like an idiot


...oh it was THAT that made him look like an idiot to you, ok...


RE: Confused...?
By Exedore on 7/31/2009 12:28:48 PM , Rating: 1
Boeing contracts out a lot of the engineering on the 787. I know one of the engineering team leaders on this project (stress analysis), and he has some European engineers working under him. I won't say what country they are from. He said he constantly has to re-do their work because it is not done correctly.
It may be Boeing's fault for not catching this mistake, but be careful who you blame for the actual source of the flaw.


RE: Confused...?
By bhieb on 7/31/2009 12:52:46 PM , Rating: 1
Yeah we all know how smart they are trucking plane parts across the country...riiighhhttt.


RE: Confused...?
By dav115 on 7/31/2009 4:27:25 PM , Rating: 1
Yeah, and while they are there maybe they can teach the French how to coordinate CAD packages between their design offices, thus avoiding the problem of not being able to add design changes to the master mockup...


RE: Confused...?
By cochy on 7/31/2009 4:44:44 PM , Rating: 1
Umm ya cause the A380 is on-time and on-budget.


RE: Confused...?
By Mclendo06 on 7/31/09, Rating: 0
RE: Confused...?
By Mclendo06 on 7/31/2009 10:32:01 PM , Rating: 2
Even if a plane will pretty much never see that load, you have to design to the FAR specifications. Period.

I'm honestly not very surprised by these issues. The 787 is the biggest leap in commercial aircraft design since the Concord. No plane has ever used composites for so much of the structure. The design is completely different. Delamination is going to be an issue with laminated composites, but they are generally better understood than woven composites, not to mention that techniques for their manufacture are further along, both of which make them a lower-risk choice overall.

The 787 is only the start in the world of composite aircraft. Once Boeing gets these kinks worked out they are going to be lightyears ahead of any other producer of commercial air transports.

One other thing - the 777 failed at 154% of maximum design load in its static test - http://www.youtube.com/watch?v=pe9PVaFGl3o - an overdesign of only 2.7%. Boeing knows how to analyze complicated structures just as well as anyone. The only problem is that failure of composites is an order of magnitude more complicated than the failure of metal...


RE: Confused...?
By Amiga500 on 8/1/2009 7:29:48 AM , Rating: 1
You think I don't know all about the FARs and JARS?

For test aircraft (i.e. not going to be used to carry passengers!), they do not have to meet the FARS/JARS. If you could guarantee meeting the regs prior to a test program, why have a test program at all? ;-)

Boeing were scared to even get the thing into the air with a restricted envelope of >2g. Says enough to me.

Oh, and you don't have to tell me about the complexity of modelling composites. Been, seen and done. I am of the opinion the 787, A350 and CSeries are a generation too early. Composites are simply not ready for the big time yet... too many unknowns, and too many inherent manufacturing problems with current processes.


RE: Confused...?
By Mclendo06 on 8/1/2009 8:00:26 PM , Rating: 2
Oh, I'm sure you do know about the FARs. Sorry, I wasn't trying to infer that you didn't. My comment was meant to be more tongue-in-cheek. I should have worded it differently.

I disagree that it's too early for a composite airplane. From discussions I've had the 787 is designed pretty conservatively overall. Yes, there will be growing pains, but everything I have seen indicates that Boeing is going to great lengths to ensure that these growing pains don't lead to catastrophic failures. The lessons they learn and the expertise their engineers are gaining will make the next composite aircraft that much better.


RE: Confused...?
By ikkeman2 on 8/7/2009 2:19:24 AM , Rating: 2
so you'd prefer a "potemkin" first flight (copyright leelaw) like their roll-out.

remember they rolled out a shell some two years ago and the uppper echelon claimed their (wet)dreamliner would be "structurally complete" in mere weeks... I guess even Boeing couldn't allow for another pr stunt like that.
They identified an error, tried to find a solution - found they had no option but a repair and decided (to do the right thing and) to implement the repair befor going forward.
Kudo's to Boeing for doing the right thing, instead of the looking good option.


"I modded down, down, down, and the flames went higher." -- Sven Olsen

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