text: typical only of a wing planform of extremely 
  high (infinite) aspect ratio. When a wing of 
  some finite aspect ratio is constructed of this 
  basic section, the principal differences will be 
  in the lift and drag characteristics-the mo- 
  ment characteristics remain essentially the 
  same. The effect of decreasing aspect ratio on 
  the lift curve is to increase the wing angle of 
  attack necessary to produce a given lift co- 
  efficient. The difference between the wing 
  angle of attack and the section angle of attack 
  
  greatest importance at low speeds and prac- 
  tically insignificant in flight at high dynamic 
  pressures. For example, a typical single en- 
  gine jet airplane at low altitude and maximum 
  level flight airspeed has an induced drag which 
  is less than 1 pcrccont of the total drag. How- 
  ever, this same airplane in steady flight 
  just 
  above the stall speed could have an induced 
  drag which is approximately 75 pnrcnt of the 
  total drag. 
  
  EFFECT OF ASPECT RATIO.  The effect 
  
  of aspect ratio on the induced drag 
  is the induced angle of attack, orit18.24 L 
  
  AR’ 
  which increases with decreasing aspect ratio. 
  The wing with 
  the lower aspect ratio is less 
  sensitive to changes in angle of attack and re- 
  quires higher angles of attack for maximum 
  lift. When the aspect ratio is very low (below 
  3 or 6) the induced angles of attack are not 
  accurately predicted by the elementary equa- 
  tion for 01~ and the graph of C, versus 01 develops 
  distinct curvature. This effect is especially 
  true at high 
  lift coefhcients where the lift 
  is 
  curve for the very low aspect ratio wing 
  very shallow and CL- and stall angle of attack 
  are less sharply defined. 