Another thing I tried to include open rotors. That not easy in terms of noise, fibration, wing-engine interference, maintenance access, ground clearance, down wash and blade containment / safety.
In the end I "ducted" the open rotor, adding drag, weight . Live is full of compromises..
The canard seems is nearly inevitable when moving on to very high BPR's / big rotors / pushers ..
Cannot see why. Most big turboprops do without canards.
But high bypass rotors would still do well if they are not blanked by the wing. The conventional props do interact with wing airflow, but this is at rather slow speeds...
I observe that Pratt and Whitney want to make a geared turbofan with 203 cm fan diametre. Producing 30 000 pounds thrust.
What plane is it meant for? A320 engines are smaller.
An existing plane which does have about 200 cm fan diametre is B757. But those engines give well over 40 000 pounds of thrust each.
Now imagine a plane which has 3 geared turbofans, 30 000 pounds thrust each. 2 underwing, the third in the tail. The MTOW is restricted by 1 engine out climbout case, 2 engines out of 3 gives more total thrust than 1 of 757... so you could support a greater MTOW than 757. And more fuel efficient, because of GTF.
What would the range be like?