What struck me when I went aboard a part-stripped 747 was the massive space above the false ceiling
I can't help wondering if you're thinking about this the wrong way around?
If I were designing an airliner cabin from scratch (which I'm not, because I'm not in the slightest bit qualified to do so!) then I might be inclined to start off building a shape which was comfortable. It would have to have flat floors so people could walk on them, and a flat-ish ceiling because that's what pax expect.
Then, I'd build around that basic box shape to make it aerodynamic. So if a flat ceiling is too draggy, I'd add a rounded section on top of it. After all, I'm not space-constrained in this direction, am I?
After that, I'd think about construction, and I might realise that it's cheape to build my design with a false ceiling. The false ceiling may make it appear that a box shape has been artificially constructed within the constraints of the fuselage, but actually it's the other way around.
I have no idea how accurate this is, it's just a discussion point. I'm not even sure if it's relevant!
FFF
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