text: moment coefficient results. Thus, when the 
  relative wind comes from 
  (+-a>, 
  a rolling moment to the left (-Cl> should be 
  created which 
  the airplane to 
  tends to roll 
  the left. 
  Lateral stability will exist when 
  the curve of C1 versus p has a negative slope 
  and the degree of stability will be a function 
  of the slope of this curve. 
  If the slope of the 
  curve is zero, neutral lateral stability exists; 
  is 
  if the slope is positive 
  present. 
  
  to sideslip. If an airplane has favorable rolling 
  moment due to sideslip, a lateral displacement 
  from wing level flight produces sideslip and 
  the sideslip creates rolling moments tending 
  to return the airplane to wing 
  level flight. 
  By this action, static lateral stability will be 
  evident. Of course, a sideslip will produce 
  yawing moments depending on the nature of 
  the static directional stability but the consid- 
  involve 
  rations of static lateral stability will 
  only the ‘relationship of rolling moments and 
  sideslip. 
  
  the right 
  
  is desirable to have lateral stability or 
  favorable roll due to sideslip. However, the 
  required magnitude of lateral stability is deter- 
  mined by many factors. Excessive roll due to 
  sideslip complicates crosswind 
  takeoff and 
  landing and may lead to undesirable oscil- 
  latory coupling with the directional motion of 
  the airplane. 
  In addition, a high lateral sta- 
  bility may combine with adverse yaw to hinder 
  rolling performance. Generally, favorable han- 
  dling qualities are obtained with a relatively 
  light-or weak positive-lateral 
  
  It 
  
  DEFINITIONS. 