Quoting Prebennorholm (Reply 36): When things are cleverly designed (and both the 787 and the 350 will turn out as some of the most fantastic structure designs in the world), then every joint will add weight. And the barrel design simply has fewer joints. |
Where are the joints?
http://www.premium-aerotec.com/Binaries/Binary4181/IMG_8171.jpg
Nobody can claim that the actual A350 barrel has more fasteners than the 787.
Quoting ArabAirX (Reply 28): Where is Ben's examination of the fact that the reason Airbus has the panel approach is because it couldn't circumvent the patents Boeing had for the one-piece fuselage design used on the 787? |
Where is your demonstration that this is a fact? Until you present sources please spare us with your facts...
Very few patents prevent competitors really to do something very similar or something as effective. Normally the patented solution can be improved or slightly changed to overcome the patent protection. Even the Airbus patent for a CFRP bulkhead did not prevent Boeing from using one for the 787 (even built by EADS!). See:
http://www.google.com/patents/about?id=kTQDAAAAEBAJQuoting XT6Wagon (Reply 37): No, Its been explained to people here time and time again that replacing a panel is *NOT* like replacing a fender on a car. |
This is correct. Replacing a barrel or a panel would only be the last measure barring scrapping.
Quoting XT6Wagon (Reply 37): Looking at the whole aspect of replacement, the panel has a tiny advantage in a D check situation where you might want to replace an extensively patched (and thus heavy) panel with a new one while the plane is gutted. |
Quoting XT6Wagon (Reply 37): The barrel has the advantage that massive damage contained to one barrel is far easier and cheaper to repair given the ability to build and stuff a whole new barrel section to swap in. |
No. Normally you want to reuse a lot of the existing undamaged material (interior, ducts, systems, sensors, avionics). And just there any cost advantage goes. With a barrel it means that you empty the existing barrel completely.
You go from this:
to this...
to this...
and if you don't want to throw away the floor to this...
(probably you have to throw away the floor anyway because otherwise the barrel's self supporting capability is no longer given).
After that you separate the barrels, rejoin the barrels (b.t.w. joining barrels requires skills that some people claim can nowhere be found unless in Seattle
WA!).
You then install the inner life of that barrel again (consult above picture series in reverse order).
........ or ........
You throw away all the inner life of the damaged barrel and simply fit in a new one! If that's what you proposed there goes any cost advantage too.
How would it work with panels:
75% of the inner stuff can stay in place... The advantage is obvious. No need to explain more.
Quoting XT6Wagon (Reply 37): Airbus talks about it being easier, but where is the massive amount of specialized equipment, planning and support for it? |
Do you still think that in the light of above picture? Just check the facts: replacing barrels requires more infrastructure that currently is in place in Boeings Final Assembly Line (FAL) in Everett. Simply because the FAL "only" joins pre-stuffed barrels. Replacing barrels on the other hand means considerable dealing with systems and interior unstuffing&stuffing.
Quoting Tdscanuck (Reply 40): To claim that it's an "advantage" on the A350 (which has panels far larger than anything currently flying) is the pinacle of irony. |
Nobody said it would be a everyday solution. It would only be an option to not scrap the plane. But in that case the panel offers advantages. I am convinced that my prediction will turn out true:
- The first written off 787 will be very premature and a case that would have been repaired in case of a metal or composite-panel plane.
But not impossible. I would say flying in the jigs is easier than to deal with the interior. At least the A350 will stay in one piece while the panel is replaced.
Quoting ArabAirX (Reply 41): Quoting Keesje (Reply 33):
The technology is not that new.
Who cares about technology, I referred to the patents! |
Which is meaningless because in fact technology gives the pace. Once a technology exists it can no longer be patented. Simple public evidence of a technology excludes a future patent because the solution fails to give the "new" aspect. From the day I present "new" technology (unproteced by patent or a application for a patent) to the public realm this technology can never be patented anymore by anyone. It is just free.
Sometimes it is better not to issue a patent anyway because the patent reveals:
- What you are researching
- Contains an exact description how you achieve something
- Reveals aspects about product strategy
- A patent delivers freely your current state of know how to the competition
- A patent allows the competition to leapfrog you by starting at your knowledge level with improvements that overcome (a.) the protection and the (b.) shortcommings of your patent.