text: where 
  
  Si = landing distance resulting from certain 
  values of landing velocity, Vi, and 
  acceleration, 6zi 
  
  S2=landing distance resulting from some 
  
  different values of landing velocity, 
  V2, or acceleration, a2 
  
  With this relationship, the effect of the many 
  variables on landing distance can be apptoxi- 
  mated. 
  
  The effect of gross wclght on landing distance 
  is one of the principal items determining the 
  landing distance of an airplane One effect 
  of an increased gross weight is that the airplane 
  require a greater speed to support the 
  will 
  airplane at 
  landing angle of attack 
  and lift coefficient. The relationship of land- 
  ing speed and gross weight would be as 
  follows: 