text: TRANSONIC AND SUPERSONIC CONFIGU- 
  
  RATIONS 
  
  PHENOMENA OF SUPERSONIC FLIGHT. 
  While many of the particular effects of super- 
  sonic flight will be presented in the detail of 
  later discussion, many general effects may be 
  anticipated. The airplane configuration must 
  have aerodynamic shapes which will have low 
  drag in compressible flow. Generally, this will 
  require airfoil sections of low thickness ratio 
  and sharp leading edges and body shapes of 
  high fineness ratio to minimize the supersonic 
  wave drag. Because of the aft movement of the 
  aerodynamic center with supersonic flow, the 
  increase in static longitudinal stability will 
  demand effective, powerful control surfaces to 
  achieve adequate controllability 
  for super- 
  sonic maneuvering. 
  
  It should be ob- 
  vious that airfoils 
  for high speed subsonic 
  flight should have high critical Mach num- 
  bers since critical Mach number defines the 
  lower 
  for shock wave formation and 
  subsequent force divergence. An additional 
  complication 
  this 
  speed range is that 
  the airfoil should have 
  a high maximum lift coefficient and sufficient 
  lift 
  thickness to allow application of high 
  devices. Otherwise an excessive wing area 
  would be required to provide maneuverability 
  and reasonable takeoff and landing speeds.  As a corollary of supersonic flight the shock 
  wave formation on the airplane may create 
  special problems outside the immediate vicinity 
  of the airplane surfaces. While 
  the shock 
  waves a great distance away from the airplane 