The singular perturbations method is used to find a simplified solution of the longitudinal aircraft dynamics. The variables are devided into slow and fast. Then the steady state fast variables are used as input to the slow subsystem. The obtained simplified solution of the short period mode is the same as previously known solution of this mode. The obtained solution of the phugoid mode is basically different from the well known appro-ximate solution of this mode. Calculations proved that the obtained appro-ximate solution is very near to the exact one.