text: The pitch damping of the airplane is obvi- 
  ously related to air density. At high altitudes, 
  the high true airspeed reduces the change in 
  tail angle of attack for a given pitching velocity 
  and reduces the pitch damping. Thus, a de- 
  crease in maneuvering stick force stability can 
  be expected with increased altitude. 
  
  TAILORING CONTROL FORCES. The 
  control 
  forces should reflect the stability of 
  the airplane but, at the same time, should be 
  of a tolerable magnitude. The design of the 
  surfaces and control system may employ an 
  infinite variety of techniques to provide satis- 
  factory control forces. 
  
  Aerodynamic balance must be thought of in 
  two different senses. First, the control surface 
  must be balanced to reduce hinge moments due 
  to changes in angle of attack. This is necessary 
  to reduce the floating tendency of the surface 
  which reduces the stick-free stability. Next, 
  aerodynamic balance can reduce the hinge 
  moments due to deflection of the control sur- 
  face. Generally, it is difficult to obtain a high 
  incurring 
  degree of deflection balance without 
  a large overbalance of the surface for changes 
  in angle of attack. 
  
  Some of the types of aerodynamic balance 
  are illustrated in figure 4.16. Thesimple horn 
  type balance employs a concentrated balance 
  area located ahead of the hinge line. The 
  balance area may extend completely to the 