text: where 
  
  A&, = moment about the aerodynamic center, 
  
  a.c., ft.-lbs. 
  
  CMa.c,=coefbcient of moment about the a.c. 
  
  q= dynamic pressure, psf 
  
  S=wing area, sq ft. 
  
  c=chord, ft. 
  
  The moment coefficient used in this equation is 
  the dimensionless ratio of the moment pressure 
  to dynamic pressure moment and is a function 
  
  ML3.C. 
  %.c. = p- 
  
  of. the shape of the airfoil mean camber line. 
  Figure 1.22 shows the moment coefficient, 
  
  49 