Patent ID: 6308913
Filing Date: 2001-10-30
Classification: B64D,Y02T

Abstract:
A method for reducing a wave resistance in an airplane, which comprises disposing a substantially cylindrical engine nacelle covering a gas turbine engine within a main flow above a rear portion of an air flow on an upper surface of a main wing of an airplane, for generating a negative pressure on the upper surface of the main wing of the airplane cruising at a transonic speed, superposing a decelerated region of the main flow generated in front of the engine nacelle onto the air flow on the upper surface of the main wing to decelerate the air flow on the upper surface of the main wing, defining the negative pressure when the air flow on the upper surface of the main wing becomes sonic speed, as a critical pressure coefficient, establishing on the wing chord a reference point at which the profile of pressure on the upper surface of the main wing is changed from a state equal to or larger than the critical pressure coefficient to a state smaller than the critical pressure coefficient, and disposing a front end of the engine nacelle to the rear of a position in front of the reference point by 5% of the length of the wing chord, thereby reducing the negative pressure on the upper surface of the main wing to inhibit the generation of a shock wave.