Originally Posted by
N6279P
Are you kidding? The weight and added drag of a larger fuselage for a second aisle is why you don't see any passenger 767-200 aircraft around anymore. It had the highest CASM for that reason alone.
The two aisles is designed to have an airplane with over 200 seats that doesn't take 45+ minutes to board and deboard. You'd need over 90 minutes to switch crews with a single-aisle 200+ seat plane. Certainly getting the plane to turn an hour is not going to happen unless they are 2 aisles with 230 seats.