NAVWEPS OO-BOT-80  STABILITY AND CONTROL  IST MODE OR PHUGOID  ANGLE OF ATTACK AT EACH  INS%;  ,,“L&blSG$~,lGH~  &  5  LoNG  PERIOD  ------I  kw  a0  f 2  -  g:  *a  2  0  2ND MODE OR SHORT PERIOD OSCILLATION  MOTION OCCURS AT ESSENTIALLY CONSTANT SPEED  L TIME TO DAMP TO  HALF AMPLITUDE  Lb--  TIME  /  /  -6.HORT  PERIOD -  UNSTABLE OSCILLATION  Figure 4.20. Longiitudinal Dynamic Sttxbility  280 