text: value all oblique portions of the waves incline 
  more greatly and the detached normal shock 
  portion of the bow wave moves closer to the 
  leading edge. 
  
  shock wave forms as the boundary between 
  the supersonic flow and the subsonic flow on 
  the aft portion of the airfoil surface. The 
  acceleration of the airflow 
  from subsonic to 
  supersonic is smooth and unaccompanied by 
  shock waves if the surface is smooth and the 
  transition gradual. However, the transition 
  of airflow 
  from supersonic to subsonic is 
  always accompanied by a shock wave and, 
  when there is no change in direction of the 
  airflow, 
  is a normal shock 
  wave. 
  
  Of course, all components of the aircraft 
  in a manner 
  
  are affected by compressibility 
  that of basic airfoil. 
  somewhat similar 
  The tail, fuselage, nacelles, canopy, etc. and 
  interference between the 
  the efkct of 
  the aircraft must be 
  various surfaces of 
  considered. 
  
  to 
  
  The airflow sepa- 
  ration induced by shock wave formation can 
  the aerody- 
  create significant variations 
  namic force coefficients. When the free stream 
  speed is greater than critical Mach number some 
  typical effects on an airfoil section are as 
  follows : 
  
  FORCE DIVERGENCE. 