turboliner
I am sure that this is not the sort of feedback that you are looking for but it may nevertheless be useful. Speaking as a passenger, I used to commute regularly between Lagos/Ibadan/Kaduna/Benin, over a period of 4 years, some time ago.
The workhorse of these routes was the F27 but occasionally an F28 was used.
There was a huge difference in ‘comfort’ between these two. The noise/vibration/harshness of the F27 was not something that one looked forward to. But more importantly, IMO, it was the limited service ceiling or cruising ceiling that made the F27 particularly uncomfortable because most of the time it could not rise above the bumpy air. The type of discomfort I am talking about is not just a regular jolt or two that people nowadays seem to refer to as turbulence. No, this was the real difficult stuff that could pin the cabin staff to the ceiling for a good few seconds, and leave one's hips bruised and chaffed by the seatbelt. I therefore developed an aversion to the F27 and their ilk. In the F28, I could often see the weather well below, and could walk straight when I got off.
Would your design be better than this for comfort? If not, passengers will eventually shun it. The answer is to design one that can get above the weather, easily. Is a 25,000ft service ceiling enough? Wasn't that the service ceiling of the Bristol Britannia in the 1950s? Surely engine and propeller technology has improved since then.
I follow your posts with interest, on Airlinersnet as well, if I am allowed to say that.
rgds