text: define the maximum 
  turning performance. 
  The acrodynomic limir describes the minimum 
  radius available to the airplane when 
  operated at C,,,,. When the airplane is at the 
  stall speed in level flight, all the lift 
  is neces- 
  sary to sustain the aircraft in flight and none 
  is available to produce a steady turn. Hence, 
  the turn radius at the stall speed is infinite. 
  As speed is increased above the stall speed, the 
  is able to develop lift greater 
  airplane at C,,, 
  than weight and produce a finite turn radius. 
  For example, at a speed twice the stall speed, 
  the airplane at CL,,,,= is able to develop a load 
  factor of four and utilize a bank angle of 75.5’ 
  (cos 75.~~ = 0.25). Continued 
  increase in 
  speed increases the load factor and bank angle 
  which 
  is available aerodynamically but, be- 
  cause of the increase in velocity and the basic 
  effect on turn radius, the turn radius approaches 
  an absolute minimum value. When C,,, 
  is 
  unaffected by velocity, the aerodynamic mini- 
  mum 
  radius approaches this absolute 
  value which is a function of C,,,,,,,, W/S, and 6. 
  Actually, 
  the one common denominator of 
  aerodynamic turning performance is the wing 
  level stall speed. 