The transverse flow effect results in what from the rear portion of the rotor disc?

The transverse flow effect is a phenomenon observed primarily in rotorcraft aerodynamics, particularly in helicopters. It occurs when the rotor blades experience a change in airflow patterns as they move through their circular path.

When considering the rear portion of the rotor disc, the transverse flow effect leads to a reduction in lift. This is primarily due to the difference in angle of attack and the airflow velocity around the rotor blades as they traverse through various parts of the rotor disc. At the rear of the disc, the blades are operating in a region where the induced flow and resultant lift characteristics are altered. The forward-moving blades are encountering a more uniform airflow, while those at the back are subjected to disturbed airflow patterns, resulting in a loss of effective lift generation.

Therefore, understanding the transverse flow effect is crucial for flight safety and performance, particularly during maneuvers that involve changes in flight speed or direction. This insight is essential for pilots in understanding how lift is influenced by rotor disc dynamics.