Originally Posted by ronstory
...Do "newer" airstreams no longer use a one-piece rib? If so... any idea when Airstream did the tranistion to no doubt the less expensive assembly?
yes, they are now 3 pieces.
actually the side and top rib sections and channels are "skinned" together with the outer panels, taped and riveted...
then the top, sides, and end caps are assembled into a shell.
so the shell is really 5 segments combined into 1, before mounting onto the floor/frame assembly.
the jigs used for the 3 semi flat sections are MUCH easier for workers to build on...
they can essentially stand or use short ladders and work without bending over much or in other odd positions.
this started around the wide body transition and really the REVISED curve/radius, but not exactly all at once.
there is NO suggestion ANYWHERE that this has to do with IMPORT of parts or that it's LESS expensive (which may be true)....
a/s CLAIMS using this technique is STRONGER than the previous approach with continuous one piece ribs...
a key part of this transition was the design of different RIB profiles, C channels, joiner bits, and other cad designed small parts...
but i don't buy the strength claim and others don't either. but the a/s engineers say otherwise.
an a/s assembly really is NOT semi-monocoque any more.
instead it is 5 fabricated sections, connected then mounted 2 a frame/floor/running gear unit.
i've posted detailed close up pictures of the 3 piece ribs, lower channels, skin and how they are joined together in past threads...
will dig 'em up later.