747-8F begins flutter testing as stringers get inspected (and other 787 items)


Boeing’s first 747-8F – RC501 – began flutter testing today from Moses Lake, after being inspected earlier in the week after Boeing and Vought Aircraft Industries discovered defective stringers supplied by a sub-tier supplier.

The stringers in question are near the aft of the 747′s iconic hump and are mounted on the inside of the aircraft’s skin and run the length of the aircraft. The concern centers around the thickness of the stringer flange, which can crack under certain loads. Boeing says the 747-8F test fleet was inspected earlier this week and cleared for flight, though two program sources I spoke with say that g loading limitations were likely to be in place until the full extent of the defective stringers could be known.
More importantly, aircraft in production are being checked for this similar problem and could prompt a time consuming repair to that would see the stringers removed and replaced. 
Meanwhile, RC522 is still carrying out Flaps 30 testing as Boeing continues to identify a permanent solution to eliminate the buffet at the maximum flap setting with the landing gear down.
Additionally, Boeing is studying adding a fourth flight test aircraft to conduct engineering test flights. RC503, the second production aircraft, the fifth 747-8F, the 1424th 747 built is the likely candidate to take part in flight test, though the company says no final decision has been made yet.
On the 787 front, ZA003 and ZA002 are set to rejoin flight test after being in ground tests and layup respectively. Following its post-Victorville maintenance, ZA002 will flight test its new software load this weekend and ZA003 testing will focus on Environmental Control System testing. ZA001 is still progressing through high speed stability & control testing, as the flight test team moves closer to the yet-achieved Type Inspection Authorization, original targeted for February.

19 Responses to 747-8F begins flutter testing as stringers get inspected (and other 787 items)

  1. HaHaHa April 10, 2010 at 5:57 am #

    My confidence in Boeing products is almost gone now. If loose wings on the 787 don’t get you, a gaping flange on the 747-8 just might. I think i’ll go by Airbus thanks!

  2. Luke (Wichita) April 10, 2010 at 9:23 am #

    I’m sure that Airbus will welcome your next purchase of a commercial aircraft, and Boeing execs are drowning their sorrows at the loss of your custom.
    Why would your confidence in Boeing suffer? Problems identified and fixed, seems like a major failure. I’m sure no other OEM has ever had a defective part in their history.

  3. Boeing Cheerleader April 10, 2010 at 9:56 am #

    Seems as if the the love child of Keesje and Zeke has crawled out of mommies basement again.

  4. empire37 April 10, 2010 at 11:03 am #

    Loss in confidence? Wait till Boeing tries delivering Charleston built 787s to customers.

  5. CM April 10, 2010 at 1:57 pm #

    HaHaHa is a wonderful provocateur, but his lack of understanding for things technical (including the products he holds a preference for) really mean none of you should take offense to the things he says here.

    Failure of the 787 SOB joint is a natural consequence of pressing technology to the bleeding edge. It was discovered in a test program that was designed to capture precisely that type of problem. It is now successfully resolved and the whole world except HaHaHa has moved on. It’s not so different from the A380′s failure of its wing ultimate load test; It’s an accepted risk when developing an efficient structure which is designed very close to zero margin. Like the 787, the A380 problem has been successfully resolved and we’ve all move on except the most embittered Boeing fanboys.

    The failure of a supplier to deliver parts produced on spec, and the failure of the quality system to capture the parts before they were installed on an airplane are without question real problems. However, anyone’s fantasy that this is a reality faced by only by one OEM is utter nonsense. To even suggest it represents a complete lack of familiarity with the industry. Anyone working in the business can recite numerous examples for any manufacturer. One reason is because (at least where systems are concerned) the whole industry is using the same supply-base.

    So, whether it’s…

    -flutter in flight test (A380 fairing / 747-8 gear door)
    -design flaws discovered the hard way (777 Fuel-Oil Heat Exchangers / A330 pitot tubes)
    -structural failures during certification tests (A380 wing / 787 wing)
    or
    -mandatory inspection and replacement of parts after aircraft are flying (747 stringers / A320 MLG door actuator fittings)

    …these are all problems which are attributable in very even ways to both Boeing and Airbus.

    Cheers!

    CM

  6. enigneer April 10, 2010 at 2:58 pm #

    HaHaHa said:
    on April 10, 2010 5:57 AM | Reply
    My confidence in Boeing products is almost gone now. If loose wings on the 787 don’t get you, a gaping flange on the 747-8 just might. I think i’ll go by Airbus thanks!

    I wondered why you call yourself HaHaHa! I see you are quite the HaHaHa on this blog yourself. I deeply sympathize.
    Even with the discount that Airbus will give you, it wil still leave burn marks on your pants because it is out of your league to afford a commercial jetliner. HaHaHa………….

  7. Anonymous April 10, 2010 at 3:28 pm #

    Before we start to lose too much confidence, let’s read Joe Sutter’s (the father of the 747) autobiography: “747: Creating the World’s First Jumbo Jet”.

    Some very interesting design and flight test issues during the -100 days are written about in this book. It puts the problems of the -8 in perspective, and they seem minor in comparison. An example for the -100 was the appearance of flutter at high speeds – an issue that required a complete redesign of the outboard nacelle struts to de-tune the frequencies of an outboard nacelle and wing vibration mode.

    What is interesting about designing airplanes in the days of the internet is the amount of information related to problems on current programs that is proliferated. It’s not a bad thing, and in many ways it’s good that the internet provides more information to the average person. But context is important- the problems aren’t new, they are just more visible. To the Boeing engineer (and yes, even the Airbus engineer), however, it’s just another day at the office.

    But despite its early problems, no one can deny that the 747 is a solid plane. By the time Boeing is done with the 747-8, I think it will continue to carry with it that reputation.

  8. Sutter Fan April 11, 2010 at 9:04 am #

    Before we start to lose too much confidence, let’s read Joe Sutter’s (the father of the 747) autobiography: “747: Creating the World’s First Jumbo Jet”.

    Outsourcing major and key components may look good on the balance sheet, but it doesn’t pay off in the long run.

    How’s that outsourcing working for you, Boeing?

  9. tom edwards April 11, 2010 at 11:54 am #

    Sutter Fan seems to have experienced a bit of flutter.

  10. HaHaHa April 11, 2010 at 12:02 pm #

    Interesting how engineer has taken ‘go by Airbus’ to mean ‘go buy Airbus’.

    Hmm!

    At no point have I said I’ll buy an Airbus that’s ridiculous – almost as ridiculous as engineers understanding of the English Language. I sympathise that your education was so under-rated.

    CM wrote…
    “HaHaHa is a wonderful provocateur, but his lack of understanding for things technical (including the products he holds a preference for) really mean none of you should take offense to the things he says here.”

    Yet people still have to try and justify in their own minds that the concurrent cock-ups of a once great Boeing are all par for the course. If Boeing can’t even get a derivative aircraft right, how can you even trust them with a ‘so-called’ revolutionary aircraft?

    The 787 is going to be bitterly disappointing to the many Boeing fan boys out there. At the end of the day, all the 787 is, is a glorified 767.

    You’ll have bigger windows (hooray!) but you’ll still be crammed in like cattle and if you think for one minute that airlines will retain the wide open, spacious interiors shown off by Boeing in their mock ups you couldn’t be more wrong. The test interior at 9 abreast is proof of that.

    I mean did you know that if airlines utilise a 9 abreast seating configuration in the 787, which many are bound to do the seat width would be comparable to that of a 737 – hardly very revolutionary comfort wise is it especially on the longer flights the 787 is designed for.

    Or maybe you weren’t aware of the fact that the 787′s much touted pressure improvements are in fact poorer than those employed in the A380 – 6,000 feet for the 787 compared with 5,000 feet for the A380.

    I think its time to accept that the more revolutionary aircraft (A380) is already in service today and a recent poll on the Flight Global website also put the A380 way ahead of the 787.

    If and when Boeing ever deliver the 787 I’m sure people won’t enjoy it as much as people who fly in the A380!

  11. The Ghost of Bill Boeing April 11, 2010 at 12:42 pm #

    No worries, folks. This actually represents an opportunity to demonstrate how good we can react to issues!

  12. Karl April 11, 2010 at 4:21 pm #

    It seems that some of us really wish Boeing bad things, including people from the State of Washington, which really does not make sense to me seems Boeing is the biggest employer of the state. I visit this blog quite often to find the latest interesting new things in aviation. I guess others are just interested in seeing what new bad things happened to some plane makers. May the entrepreneur engineering spirit prevail!!!

  13. snogglethorpe April 11, 2010 at 7:44 pm #

    This site acquired a lot of rather dim trolls around the time of the the last strike at Boeing, who have a tendency to just randomly spew bile in the comments.

  14. snogglethorpe April 11, 2010 at 10:29 pm #

    (sorry for the dup — got a “Server error” after posting and made the mistake of trying again…)

  15. Cartoons and airplanes April 12, 2010 at 9:10 am #

    If only the little stick figure was a guy http://xkcd.com/726/

  16. Jon Ostrower April 12, 2010 at 9:34 am #

    Thanks, Cartoons and airplanes. That’s pretty awesome. XKCD always comes through. Still disappointed I didn’t get to pick my seat on this one: http://bit.ly/c9k2kD

    -Jon

  17. Todd April 12, 2010 at 10:37 am #

    HaHaHa

    Whether your reaction is to travel via or buy an airbus is irrelevant. HC does a good job of articulating that your inflammatory reaction was based upon a lack of information.

  18. Paulo M April 12, 2010 at 12:56 pm #

    You come with no reason. The purpose of the extensive tests on aircraft (and everything else) is to validate & verify. And where necessary, make amendments to the design.

    This particular stringer issue on the 747-8 is testament to how much the design process changed for the 747 – and, indeed, how much of a change the 747-8 is over the 747-400. But I’m just following all this as the 747 moves from paper to CAD.

    Do view Plastic Fantastic in full stretch pose with regards that SOB trouble you’re having.

    ———

    With regards the English Language, it is underrated not under-rated. ;)

  19. UncleRon January 19, 2011 at 2:16 pm #

    HaHaHa to you too. Sure, I’d stack ANYTHING Boeing has put in the air in the last 30 years against EVERYTHING Airbus has put up. Go on over to Airbus. More room for us on well designed, carefully engineered Boeing products.

    Uncle Ron