12.4: Point mass model
- Page ID
- 77999
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The translational equations (12.3.1.10)-(12.3.1.12) are uncoupled from the rotational equations (12.3.1.13)-(12.3.1.15) by assuming that the airplane rotational rates are small and that control surface deflections do not affect forces. This leads to consider a 3 Degree Of Freedom (DOF) dynamic model that describes the point variable-mass motion of the aircraft.
Under this hypothesis, the translational problem (performances) can be studied separately from the rotational problem (control and stability).