7 Flight Mystery and Aerodynamic Principles
577
Fig. 7.178 Winglet lift increment and pull effect
Fig. 7.179 Wasp waist body design of H-6
by the longitudinal distribution of its cross-sectional area, and is the same as
the revolutionary body with the same cross-sectional area distribution. That
is to say, the shape of the cross-sectional area of the aircraft in the longitudinal position has no effect on the wave drag. What has an effect is the
change mode of the size of the cross-sectional area in the longitudinal direction. When the traditional straight fuselage passes through the wing, the wave
drag will increase obviously. If the wasp waist structure is adopted, the wave
drag can be greatly reduced. Therefore, the transonic area law is proposed to
reduce the zero-lift wave drag by modifying the fuselage. It is found through
experiments that the area law can reduce the zero-lift drag by 25–30%, but
with the increase in Mach number, the drag reduction effect of the area law
577
Fig. 7.178 Winglet lift increment and pull effect
Fig. 7.179 Wasp waist body design of H-6
by the longitudinal distribution of its cross-sectional area, and is the same as
the revolutionary body with the same cross-sectional area distribution. That
is to say, the shape of the cross-sectional area of the aircraft in the longitudinal position has no effect on the wave drag. What has an effect is the
change mode of the size of the cross-sectional area in the longitudinal direction. When the traditional straight fuselage passes through the wing, the wave
drag will increase obviously. If the wasp waist structure is adopted, the wave
drag can be greatly reduced. Therefore, the transonic area law is proposed to
reduce the zero-lift wave drag by modifying the fuselage. It is found through
experiments that the area law can reduce the zero-lift drag by 25–30%, but
with the increase in Mach number, the drag reduction effect of the area law