From footage I've seen about the A350 fuselage panel construction, this looks like a really time-consuming labor and machining intensive proces. Thus really expansive.
Here is an example: https://m.youtube.com/watch?v=6_R54EVDdf0
And another one that shows another eliminatable logistics step: Example 2
If they swap tap laying for 2D fabrics the cost will most likely reduce a lot. The winding proces Boeing uses is most likely also faster.
But I can't undo myself from the impression that fuselage can beter be made from Alu-Li sheets and extruded profiles joined by stirfriction welding. The weightsavings on 2D-omnidirectional loaded parts from CFRP compared to Alu is minimal. I expect lower CFRP content on new clean sheet designs. This also leads to production cost savings.
I'm also far from convinced there isn't degredation in CFRP parts. If degradation occurs CFRP parts don't show it, while alu does, leading to spontaneous failures. I hope I'm wrong because this could become really ugly. Aka 737MAX trouble squared.
thanks for finding the videos.. yes they are time consuming and worse yet when one attaches all the panels to the section frame, you have edge imperfections that lead to two other problems, hand working to fit and fair.. and water penetration leading to delimitation if not sealed correctly. Airbus justifiably prides itself of owning and using the latest technology and robotics, the problem is these advances are not always used to improve production processes or costs and frequently are gee whiz publicity moments. Question why are the wing skins made in Spain the transported to Wales.. this removes problem correction from the simple category to the complex. By comparison, the 777x wing skins are made adjacent to the wing assembly line, and the engineers, tech, and support personal are within walking distance (although many use bicycles) to resolve issues quickly. For process improvement the skins should be manufactured in Wales, as well as other post assembly processes so the wing can be shipped directly to the installation point with a minimum of touches.
Firstly as a fellow manufacturing engineer I have huge respect for your knowledge and experience.
I need to make some comments with respect to your post, though.
The set of videos I watched, and then compared to videos of the 787 barrels being manufactured suggested that there are no major differences besides the obvious one (panel vs barrels). I also struggled to see the panel manufacture itself as "labour intensive" when the only thing you see is a robot laying machine.
Multi site/multi nation manufacturing is a regular feature of modern major programmes required to establish the partnering demanded by scale.
And Boeing do it in much the same way Airbus do - perhaps not to the same extent.
The problems it brings demand their own set of countermeasures.
Amongst the foremost of these are stricttly governed "condition of supply" criteriea relating to the effective management of key design or build features through the lifecycle, together with advanced 3D predictive metrology.
A colleague I work with is a senior metrology specialist (as am I), and came to us from Airbus via another "multi-national programme".
He has an advantage over me as his specialisation is exclusively aerospace.
The electronic 3D predictive metrology processes that were implemented in this instance on the A350, across continents, guarantee fit ups as close as 0.02mm, or 1/1300 of an inch, which is adequate to guarantee first time fit up in the downstream assembly. It is a discipline (alongside the strict condition of supply criteria) that has to be grown in order to successfully execute distributive manufacturing.
Developing those disciplines, to quote your own phrase back at you, removes the problem correction from the complex to the simple.
All I can say is that if Boeing are experiencing "hand fit and fair" on these types of assembly, in this day and age then they are doing something wrong.
I do wonder if, say for example, in the 777 manufacture, where the assembly processes are alongside each other, it can appear that you actually have the option of "travelling the fix" because it is easy. Also as an older design it won't be embedded in the digital thread to the same extent as the 787 or A350
If you are manufacturing in different nations, or even continents, that travelled fix problem as you say would be more complex..
The best way to deal with a complex problem is not to have it in the first place.
Which is how the controls I describe have evolved.
I would rely on you to tell me, but I would be surprised if Boeing were travelling fit up fixes on the 787 barrels which are manifactured all over the place.
That's the best way to completely ruin the advantages of pre-stuffing, which have (rightly) been touted on this forum.
Believe me I know. I've been there
Last edited by astuteman
on Wed Jun 26, 2019 3:40 am, edited 1 time in total.