text: in supersonic 
  flow 
  facts. AS 
  shown in figure 3.18, Mach cones form at the 
  tips of the rectangular wing and affect t~he 
  the 
  pressure distribution on the area within 
  cone. The vortex develops within 
  the tip 
  cone due to the pressure differenti,al and the 
  resulting average pressure on the area within 
  thecone is approximately one-half the pressure 
  between the cones. Three-dimensional flow 
  on the wing is then confined to the area within 
  the area between the 
  the tip cones, while 
  cones experiences pure two-dimensional flow. 
  the three- 
  dimensional flow on the rectangular wing in 
  supersonic flight differs greatly from that of 
  subsonic flight. A wing of finite aspect ratio 
  in subsonic flight experiences a three-dimen- 
  includes the tip vortices, 
  sional flow which 
  downwash behind the wing, upwash ahead of 
  the wing, and local induced velocities along 
  the span. Recall that the local induced veloc- 
  ities along the span of the wing would incline 
  the section lift aft relative to the free stream 
  and result in “induced drag.” 
  Such a flow 
  condition cannot be directly correlated with 
  the wing in supersonic flow, ~ The flow pattern 
  for the rectangular wing of figure 3.18 dem- 
  is 
  onstrates that 
  confined to the tip, and pure two-dimensional 
  flow exists on the wing area between the tip 
  cones. 
  flow 
  outside the tip cones, the entire wing 
  would correspond to the two-dimensional (or 
  section) conditions. 