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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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Shane can piss off
By rudolphna on 7/31/2009 11:44:43 AM , Rating: -1
Oh shane you are such an airbus fanboy. You talk like these aren't normal occurences when a company designs an ENTIRELY new type of construction, on something as massive and complex as a commercial airliner. Think about it. I'll use toyota so people don't bite my head off about the reliability thing. (Personally I think ford is best but I don't want to get into that now) Take a Camry. Brand new. Drive it all day, everyday for years and years. Give it about a year and a half, and its going to probably start falling apart. Planes do that All the time.

Nobody should be surprised that faults show up. This is completely different than what they have ever done before. Shane makes it sound like "How dare they mess up and it's not perfect". Well that kind of thinking from a supposed "Tech writer" is unacceptable. Airbus, Bombardier and more all have problems and kinks to work out in new airplanes. The 787 will likely have more because of the nature of the project. Frankly I'm glad they are finding the flaws NOW, as opposed to later after a couple years of service. Anyone who expects something as massively complicated as a commercial airliner to be absolutely trouble, defect, free before even ever flying, needs to go dunk his/her head in a bucket of ice water.

RE: Shane can piss off
By FaaR on 7/31/2009 12:19:31 PM , Rating: 2
Airbus fanboy... El-oh-el, I never thought I'd see that particular accusation being used. If you want to name anyone as a fanboy, I'd look in a mirror pally, considering how defensive you act in your post, heh.

One might wonder what's even the point of pontificating over particular aircraft manufacturers anyway, considering A: we as passengers have absolutely no control over which make of airplane we get to travel in, the airliner takes care of that. And, B: nobody except the stupidly rich could afford to buy one of these babies to begin with.

As for Dreamliner being an 'entirely new' design, no it isn't. Not even close. For starters, it follows the same basic concept passenger planes have used since roughly the 1930s, and even more closely related, other jet airplanes from the 1960s.

It's a traditional airplane, with composite materials used in the airframe. Composites btw aren't new tech either I might add, they've been used for decades in the aircraft industry.

RE: Shane can piss off
By rudolphna on 7/31/2009 12:31:20 PM , Rating: 2
I'm not a fanboy. I would be defending airbus or bombardier or Lockheed if they had these problems too. You CAN pick the plane you fly in. You can pick your airline, and it tells you for each flight the planes. You can pick and choose as you want. Also, it IS a new design. This is the first time a commercial airliner, or any large aircraft has EVER used composite materials for the entire airframe construction. That means nobody truly knows what to expect, and guesses are pretty much the best that can be done.

RE: Shane can piss off
By brybir on 7/31/2009 3:02:11 PM , Rating: 2
You seem pretty frantic about this issue. Somehow you read into this article that the implication is that the Dreamliner should be trouble free, and then go on and on about how unrealistic it is that this amazing new aircraft should not have any problems.

Best I can tell from the article is that it says:

1. The project is delayed well past Boeing's own internal schedule of development
2. The delays are attributed to defects found in the design during testing
3. Repeated delays of this kind are not good in a very competitive industry.

I fail to see how any of this represents "fanboyism". I also do not see where it appears the author is advocating anything. I think its a pretty good short article about the problems Boeing is having, the context and history of other problems of the plane, and the possible implications this could have in the industry that Boeing competes in.

I didnt even know people could be "fanboys" for an airline. Seems kinda silly to me unless perhaps you work for the company or are directly impacted by it.

RE: Shane can piss off
By Belard on 7/31/2009 4:38:57 PM , Rating: 2
Geez people... both of you don't know what a fanboy is.

Rudolphna defends Boeing on equal footing as any other airplane maker.

A fan boy does this: "AIRBUS SUCK IT DOWN!! BOEING ROCKS! Say anything wrong with Boeing, I'll knife you!"

The delays in the 787 are not good, but nothing shocking. That is what the stress tests are for. Hopefully Boeing doesn't get to much problems from the Airliners... each delay costs Boeing money in not making their deliveries and the penalties by the Airliners. ie: Each plane delayed could cost Boeing thousands of dollars per day.

RE: Shane can piss off
By FPP on 8/3/2009 7:22:45 PM , Rating: 2
nonsense! With far fewer design tools, an earlier generation of engineers took less time and got a far better result, while taking far larger risks.

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