787 first flight
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787 problems
Seeing the Varsity and the Anglia does remind one about the questionable aesthetic design capability of some. And I don’t think anyone can seriously claim these designs were necessary to allow function over form. At least Boeing is not afflicted with that malaise, as far as I can remember.
The 787, or dreamliner as some still call it (although I thought that appellation is more correctly used when describing the extra fast but subsonic effort that nobody wanted, except perhaps passengers) has a pleasing appearance. It is unfortunate for Boeing that they have run into the present crop of difficulties; and the most difficult to overcome would appear to be the elimination of “hard spots”.
As I understand it, CFRP wings, like their aluminium brothers, are required to flap, and flap they do. The problem comes at the join to the fuselage, which is too stiff. So instead of dissipating the flapping energy smoothly throughout the length of the structure of the fuselage, it comes up against one or more of these immovable “hard spots”, and the structure starts “crazing” and delaminating. In other words, it all comes unstuck. The description of the ‘fix’ is simple: make everything more flexible. In practice this looks as though it may be rather difficult, as modification to the structure of the wingbox may be required. If so, this goes right to the heart of the aircraft.
I am neither a structural engineer nor a CFRP wallah and it would be really nice and comforting if some such person could say that my suppositions are all wrong. It would be even nicer if someone from Boeing’s PR Department could help me, and probably many thousands of others, reconcile their statements or comments at the Paris Air show, with the reality of what now appears to be the case. Boeing is, or was, one of those companies, about which one felt that whatever ‘happened’ as reported by the media, they would pull through, and everything would be fine. I look on various sites, hoping that I might come across the essence of this, but so far, I have not seen that glimmer of hope. Maybe tomorrow? Or is that mañana.
The 787, or dreamliner as some still call it (although I thought that appellation is more correctly used when describing the extra fast but subsonic effort that nobody wanted, except perhaps passengers) has a pleasing appearance. It is unfortunate for Boeing that they have run into the present crop of difficulties; and the most difficult to overcome would appear to be the elimination of “hard spots”.
As I understand it, CFRP wings, like their aluminium brothers, are required to flap, and flap they do. The problem comes at the join to the fuselage, which is too stiff. So instead of dissipating the flapping energy smoothly throughout the length of the structure of the fuselage, it comes up against one or more of these immovable “hard spots”, and the structure starts “crazing” and delaminating. In other words, it all comes unstuck. The description of the ‘fix’ is simple: make everything more flexible. In practice this looks as though it may be rather difficult, as modification to the structure of the wingbox may be required. If so, this goes right to the heart of the aircraft.
I am neither a structural engineer nor a CFRP wallah and it would be really nice and comforting if some such person could say that my suppositions are all wrong. It would be even nicer if someone from Boeing’s PR Department could help me, and probably many thousands of others, reconcile their statements or comments at the Paris Air show, with the reality of what now appears to be the case. Boeing is, or was, one of those companies, about which one felt that whatever ‘happened’ as reported by the media, they would pull through, and everything would be fine. I look on various sites, hoping that I might come across the essence of this, but so far, I have not seen that glimmer of hope. Maybe tomorrow? Or is that mañana.
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Remember, the whole fuselage is made of CFRP. Has its durability to the rigours of commercial flight been tested, esp as some operators would be using it on short hops increasing its landing and pressurization cycles. Has the idea of CFRP fatigue ever been studied, like the Aloha 737 ?
And what about the electric brakes, thermal heating strips, and electric packs ? Have all this been tested to the rigours of commercial flights as well ? It would be interesting to see the dispatch reliability of the B787 in its first year. I sincerely hope Boeing can prove me wrong.
BTW, what's the propeller a/c in the pic ? Is it a pax or a freighter ?
And what about the electric brakes, thermal heating strips, and electric packs ? Have all this been tested to the rigours of commercial flights as well ? It would be interesting to see the dispatch reliability of the B787 in its first year. I sincerely hope Boeing can prove me wrong.
BTW, what's the propeller a/c in the pic ? Is it a pax or a freighter ?
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Hey Folks,
Spare some pellets in your shotguns !!!, boeing is a "Alma mater" as far as Aircrafts are concerned, glitches notwithstanding I am sure they would have considered all pros and cons before assembling the aircraft, or have you guys forgotten about different softwares being used by Airbus on A380, specially when it was supposed to be a coordinated venture between various production facilities ? which eventually resulted in top dog being escorted out of premises and Mr Leahy losing half his weight.
Nothing against A380, I think its aesthetically pleasing, given its mammoth proportions, they have done an excellent job.
Spare some pellets in your shotguns !!!, boeing is a "Alma mater" as far as Aircrafts are concerned, glitches notwithstanding I am sure they would have considered all pros and cons before assembling the aircraft, or have you guys forgotten about different softwares being used by Airbus on A380, specially when it was supposed to be a coordinated venture between various production facilities ? which eventually resulted in top dog being escorted out of premises and Mr Leahy losing half his weight.
Nothing against A380, I think its aesthetically pleasing, given its mammoth proportions, they have done an excellent job.
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787
Hi Boe 777. Re your comment “…glitches notwithstanding I am sure they would have considered all pros and cons before assembling the aircraft……” it does not look like it to me, and I doubt that it looks like that to anyone. The main point is surely not that it is late, or how it’s lateness compares with the development of other aircraft past or present; the main point is surely why it is late. In short, they cannot get the wings to stick on properly without damaging the rest of the aircraft. This is a problem of a different order of magnitude involving the main structure of the aircraft, as can be seen from this video KIRO 7 Eyewitness News Video, Seattle, Western Washington
It does not look like it is going to fly anytime soon. It is a sitting duck, and no one needs to waste pellets on that.
It does not look like it is going to fly anytime soon. It is a sitting duck, and no one needs to waste pellets on that.
or dreamliner as some still call it (although I thought that appellation is more correctly used when describing the extra fast but subsonic effort that nobody wanted, except perhaps passengers)
BTW, wasn't the Dreamliner name for the 787 thought up by some school kid in a Boeing "name that plane" competition?
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Groundloop, Hi, and thanks for straightening that out for me. I remember now. Here is the link http://www.boeing.com/commercial/news/feature/dreamliner.html
Great PR in those days.
rgds, pf
Great PR in those days.
rgds, pf
