Transitional lift results from which of the following?

Transitional lift is a phenomenon experienced by helicopters and other rotary-wing aircraft during flight, particularly when transitioning between forward flight and hovering. It occurs when the rotor blades begin to generate more lift as airspeed increases, allowing for a more efficient lift generation.

Increased rotor efficiency is primarily responsible for transitional lift because, as the rotor blades move through the air at higher speeds, they can harness more of the available airflow to produce lift. This is due to the angle of attack of the blades changing favorably at higher speeds, which enhances lift without a corresponding increase in drag.

The other factors, while they play roles in flight performance and dynamics, do not primarily cause transitional lift. Reduced drag contributes to overall efficiency and might help in achieving smoother transitions, but it is not the direct mechanism behind transitional lift. Aerodynamic stall deals with a loss of lift when the angle of attack exceeds a critical point, which is opposite to what occurs during transitional lift. Wind shear refers to sudden changes in wind speed or direction that can impact flight stability but does not specifically account for the generation of transitional lift itself.