That's correct, essentially you can apply Newton's law (F = dp/dt): the propellers over wings can produce a strong downward momentum flux (air flux) that by rea

That's correct, essentially you can apply Newton's law (F = dp/dt): the propellers over wings can produce a strong downward momentum flux (air flux) that by reaction generates lift (upward force). Without this flux being directly controllable by the wings (or steerable in other ways), you need to rely on the vehicle's airspeed to generate sufficient airflow on the wings to produce lift (so you'd expect greater takeoff speed/distance necessary). You might wonder also about efficiency. Generally the energy efficiency of an aircraft is dictated by 1) friction losses 2) outgoing airstream velocity. The lower the friction and the slower you can push an air stream the more efficient the aircraft ((2) is because the kinetic energy imparted on the air is quadratic on speed, while the momentum, and force, is only linear in speed). That's why high-bypass turbofans are now the norm (more air at slower speeds). And why you want a large propeller surface of low speed (I expect at very large propellers you get diminishing/negative returns due to additional drag), which can be few large props or many smaller props (which have the previously discussed advantages).