text: the airspeed corresponding to point A, the 
  power or thrust required curves define a par- 
  ticular value of thrust or power that must be 
  made available from the powerplant ~to achieve 
  equilibrium. Some different airspeed such as 
  that corresponding to point B changes the 
  value of thrust or power required to achieve 
  equilibrium. Of course, the change of air- 
  to point B also would require a change 
  
  The various items of airplane performance 
  result from the combination of airplane and 
  powerplant characteristics. The aerodynamic 
  characteristics of the airplane generally define 
  the power and thrust requirements at various 
  conditions of 
  the powerplant 
  characteristics generally define the power and 
  thrust available at various conditions of flight. 
  The matching of the aerodynamic configura- 
  tion with the powerplant will be accomplished 
  to provide maximum performance at the speci- 
  fic design condition, e.g., range, endurance, 
  climb, etc. 
  
  speed 
  
  in angle of attack to maintain a constant lift 
  equal to the airplane weight. Similarly, 
  to 
  establish airspeed and achieve equilibrium at 
  point C will require a particular angle of attack 
  and powerplant thrust or power. 
  In this case, 
  flight at point C would be in the vicinity of 
  the minimum flying speed and a major portion 
  of the ,thrust or power required would be due 
  to induced drag. 