787 grounding not “safety-of-flight” issue

The temporary grounding of the Boeing 787 flight test airplanes to deal with the latest assembly issues is not a safety-of-flight issue and was not sought by the flight test crews, says Scott Fancher, program manager.

The Seattle Times reported the cessation of flight tests yesterday. Boeing disputes the term “grounded” and says the flights are discontinued until inspections and repairs are completed.

In a telephone press conference this morning, Fancher says the problem with shims and fasteners in the horizontal tails assembled by Italy’s Alenia stem from improper gaps surrounding the shims and too much torque on the fasteners.

There are 25 tailplanes that require inspections, not all of which are on airplanes. Fancher refused to specify if any of the five operational test airplanes have been found with defective workmanship. The sixth airplane is still in the Everett hangar and is scheduled to fly in July.

It takes a day per plane to inspect the tailplane and up to eight days to make repairs, if needed. Two test airplanes were in flying mode when the decision came down to suspend flight testing. The other three were in planned “lay-ups,” which means scheduled ground testing and maintenance. These airplanes now are undergoing concurrent tailplane inspections.

Test airplane #2 was scheduled to fly today but is grounded pending inspection and possible repairs. Test airplane 3, the other currently flying airplane, is also grounded for inspection and potential repair.

“We made the decision to prioritize the inspections before flying airplanes 2 and 3,” Fancher said. “This is not a design issue. This is a straight-forward workmanship issue. As we went through the day we made the prudent decision to hold off flying 2 and 3, which are ones flying now.”

The shim issue emerged last week and flight restrictions were imposed over the weekend. Fancher said the flight test crews were informed but the decision to terminate flight testing pending inspections and repairs was made by the engineers.

“Gaps were larger than design allows. Put in TOL (temporary operating limitation),” Fancher said. “During the day yesterday began getting information about the torque [of the fasteners], and we wanted time to understand it. I’m not telling you it was a safety of flight issue. We reacted conservatively. The process here works. In this situation, this was a build quality and an engineering issue.”

There are two shims and 24 fasteners, equally divided on both sides.

Fancher said despite any repairs and interruption in the flight test schedule, first delivery to All Nippon Airways is still scheduled by the end of the year.

Fancher also announced that there will another re-sequencing of the delivery flow through the global production system, similar to that which occurred in May for 24 days but on a different scale and scope. The May re-sequencing involved major fuselage components. This re-sequencing involving other systems.

The result will be that some customers in 2010 and 2011 may see deliveries delayed but the total number of airplanes delivered in the year will remain as projected.

14 Comments on “787 grounding not “safety-of-flight” issue

  1. This doesn’t sound like as big an issue as the body join section problem was. It should not effect sending ZA-003 to Farnborough next month, either.

  2. The saga continues !

    This is just a Farce now, and of course that is not Boeing fault.

  3. Sure would be nice if BA got its PR facts in order, and gave out a consistent story..

    Supposed to be ahead of the PR and stories by the press

    but since miss- management has yet to figure out that post it notes and power point rangers and fresh MBAs do not understand about the facts of life in aerospace- and that faster -better-cheaper is rarely ALL three or even two. the beatings will continue until morale and PR improve.

    When not outsource the rest of the executive suite, keep and pay the real workers and engineers who have to fix the bad decisions by mr post it ??

  4. Shimming or packing is a totally standard procedure when aligning two pieces of equipment to each other.
    Its used all the time when coupling engines to generators or pumps as an example.
    What disturbs me about the Seattle times article is the suggestion that the shims became distorted during the tightening procedure.
    Without a drawing or sketch to assist, it infers that two surfaces were bolted together that were not parallel to each other.
    If so, that is bad!

  5. what bothers me more are the comments in a few articles that the shims are composite and compressible.

    Given various material compatibility problems with composites such as aluminum and graphite or graphite epoxy ( makes a swell battery ) , and recalling many many years ago that shim stock was usually brass or stainless steel, I admit to being puzzled by the compressible comments

    So called Overtorquing of fasteners involved indicates they are not using a variation of either huck process ( swaged collar ) or hi lok fasteners for which the collar torques off at a load defined by the collar manufacturing process. And the common problem there is to have excess protrusion ( grip ) ( too long a fastener for the stack ) for the parts. So the collar bottoms out on the end of the threads on the shank, torque increases and hex portion twists off ( torgue ) before the part(s) are properly pulled together, leaving a gap.

    Or they are using the wrong collars which could cause a very high torque- and pulling the couuntersink or flat tension head into or thru the composite part.

    IF then latter that issue should have been caught almost immediately on assembly inspection or long before installation on an aircraft.

    Somehow the boeing PR story doesn’t quite hang together.

    • They’re talking about the attachment of the horizontal stabiliser to the fuselage… these are not little Huck-bolts – they are likely to be inch-thick monsters.

      Likewise, the shim – which is probably composite precisely because that’s the most compatible with the outer skin panels (rather than the metal tail-to-fuselage fitting that everything’s being bolted to here), is also going to be in the order of centimetres thick rather than millimetres.

      What’s interesting to me is that this sounds like an extreme example of stress-relaxation due to resin-creep of the composites… an issue even for properly-torqued joints.

  6. How is it that Boeing only now is finding this out? How many of these horizontal stabilizers are attached to planes or aft sections which have already been built and which Boeing desperately wants to deliver in deliver in 2011? (Albaugh said in his recent investors presentation that Boeing had to start getting all their burgeoning 787/747-8 inventory off the lot and into the hands of customer so they could stary making some money.) Will these belated findings affect those deliveries negatively? How much will it cost to repair the defects?

    Once again, the awful stench of Boeing incompetence and an inability or refusal to supervise suppliers wafts our way. If Boeing cannot until now spot a problem that is physically observable (as opposed to one that is concealed within a structure), how can anyone rely on their claims that all the 787’s composite related problems or conserns have been solved? Not me. I am just disgusted with them, yet again.

  7. It would be better to understand the nature and scope of the stabilizer issue before drawing any conclusions.

    The press has distorted the story and Boeing has refuted some points and indicated that there was a need to do some inspections before coming to any resolution.

    I hope Boeing will be forthcoming and this matter. It has clearly stated that it will not interfere with the testing schedule or the delivery dates

    • It is imho not clear _where_ the distortion field has been activated 😉

  8. Uwe,

    As I followed the story, the first news was that Boeing had “grounded” the test planes. I believe this came from a Seattle paper.

    Given that as a starter, it fueled all sorts of speculation…including comments on the bloggers pages.

    Boeing and Randy Tinseth finally issued a refutation and indicated that a stabiizer issue had been located on one of the planes being completed and this would result in inspections of all planes , especially and with priority, the test planes.

    The question still remains to my mind as to the extent of the problem. That question has not been determined yet or , at least, not clarified. I also suspect that since this involves the test planes, Boeing will not make further comments but will do the necessary work during layovers and ground testing thus minimizing any further attention to this matter.

    So the real question is who is distorting the information…Beoing or the press

    • Mr. Tinseth gets paid for doing that blog.( by Boeing, I guess 😉
      And Boeing is not exactly known for giving away neutral and factual
      information.

      As it is they seem to be rather good at “gilding the lily”
      sometimes by posting unconnected information with insinuated
      interconnections or vice versa.

      Very interesting to observe.

      If as explained the problem was found in the FAL my guess would be
      that at least a second frame exhibited similar issues before any hasty
      inspections would be triggered. ( just too easy to have a peek at the other
      two dozend frames standing around. )

      Another probable explanation might be that a different more pressing
      ( but publicly unknown) issue was fixed during the “inspections”.

      The duck will have its “Swan Test” at Farnborough : present or not present ?

      • Oh, I am sure it will be there. Even if they have to stick it on a barge and haul it across the pond.
        Not that I believe such measures shall be necessary!

  9. Both planes are flying although with some limitations.

    The scope has not been determined yet and the repairs, if necessary, will take approximately a week.

    This is not a calamity. It will be attended too.

    It is the skeptics who wish to make a bigger deal of this and exaggerate the progress being made.

    Jon Ostrower is at the Alenia factpry this week and we will be hearing more about it from there. I am sure ZA2003 will be at Farnborough

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