Drag Reduction Effect of a Variable Camber Wing of a Transport Aircraft Based on Trailing Edge Flap Deflection of Small Angles

摘要

The improvement of the lift to drag ratio (L/D), and the decrease of the required power for flight, are important measures to enhance the range and endurance of propeller aircrafts. The research investigates the effect of variable camber wing on the flight performance of a transport aircraft based on wind tunnel tests. The wing camber is altered by deflect the trailing edge flap in small angles. The tests reveal that the maximum L/D reaches its peak when the flap deflects 6°, and is 4.0% higher than the configuration with flap retracted. With flap deflecting 6°. the lift coefficient for the maximum L/D is 16.1% higher. The flight performance analysis shows that the range and the endurance increase by 4.0% and 13.7% respectively at the selected flap angle. By flying at larger lift coefficient and larger L/D. the required power for endurance flight decreases significantly, which is the reason for the improvement of the range and endurance performance.