The issue isn't the bank angle exactly, it is the acceleration of the roll. Pilots will need to be careful not to throw people or drinks around, but I think it would be doable.
That said there is a fair about of wiggle room so I doubt it’s a significant issue in practice.
I even have a cool name word to describe it: "lid"!
But even beyond that feeling like you’re falling out of your seat is unpleasant.
You do sometimes see cup holders on private airplanes, but in commercial aviation the efficient solution is to avoid needing them.
Similarly, adding decent cupholders to airplanes is not going to reduce passenger space.
As to why no cup holders, people aren’t going to use them most of the time and they don’t even help that much in turbulence.
You could for example more slowly enter a higher bank angle to have an equally fast turn though passengers would feel more pressed into their seats etc.
Turbulence causing roll upsets seems like it could be a larger issue.
The ground is whatever you accelerate towards.
https://www.boldmethod.com/learn-to-fly/aerodynamics/the-aer...
A coordinated turn with 60 degrees bank should be achievable by any airworthy airplane (it requires pulling 2g), and the maximum bank angle for a steady-state coordinated turn depends on how many g you can pull before you run out of control authority, cause an accelerated stall, or reach the airframe's structural limit.
Next time you fly, get a beverage of your choice and observe how it behaves. Here's an example, courtesy of the great test pilot Bob Hoover:
At least it's never happened to me, but I am only a passenger.
The point is that air currents powerful enough to appreciably affect a large plane are large scale and therefore you're unlikely to have enough differential pressure from one wing to the other to impart much torque.
I'm not certain about this and I'd love to be corrected if I'm wrong.
It would work if all turns were managed via controls to be a 1/4g, otherwise riding the outside would be like a roller coaster.
I'd prefer to go back to the MD-80. Very high wing loading, fast and never broke down. Skated through turbulence.
Anyway, the resulting company is too large to fail, and thus, too large to exist. We're at a point where we could really use the competition we had in aerospace companies back in the 80s, when there were enough competitors in both military and commercial aviation for competitive pressures to keep the players working to provide innovation and value. (Rather than milking the market with intentionally poor designs a la Boeing's 737MAX.) Modern airlines have only two vendors to choose from now that Boeing and Airbus have gobbled up even their second-tier competitors.
Personally, I'd love to see what the old Convair, LTV, pre-Martin Lockheed, or pre-McDonnell Douglas might come up with in this competition...
A new aircraft development is a $15B+ R&D investment, for the price and fuel efficiency and safety required. McDonnell-Douglass and more recently Bombardier messed up their bets and it cost them their independent existence.
closest modern aircraft to it is the 717/MD90, which Delta is still flying, but not for much longer iirc
But on the other hand, I've never experienced turbulence that's made me more than barely uncomfortable in any plane.