# 7.2: Stability and control

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In Section 7.1 we have studied the performances of the aircraft, modeling the aircraft as a 3DOF solid and studying the point mass model movement due to external actions. In this section we study the fundamentals of stability and control, considering the aircraft as a 6DOF6 model, so that we must take into consideration the geometric dimensions, the distribution of mass, and thus we study the external forces and torques which define the movement of the center of gravity and the orientation and angular velocity of the aircraft.

Figure 7.10: Diagram showing the three main cases for aircraft pitch static stability, following a pitch disturbance: Aircraft is statically stable (corrects attitude); Aircraft is statically neutral (does not correct attitude); Aircraft is statically unstable (exacerbates attitude disturbance). © User:Ariadacapo / Wikimedia Commons / CC0-1.0.

6. Please refer to Appendix A for the deduction of the 6-DOF equations.

7.2: Stability and control is shared under a CC BY-SA 3.0 license and was authored, remixed, and/or curated by Manuel Soler Arnedo via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.