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Calculate forces used by fourth-order point mass

**Library:**Aerospace Blockset / Equations of Motion / Point Mass

The 4th Order Point Mass Forces (Longitudinal) block calculates the applied forces for a single point mass or multiple point masses. For more information on the system for the applied forces, see Algorithms.

The flat Earth reference frame is considered inertial, an approximation that allows the forces due to the Earth motion relative to the "fixed stars" to be neglected.

The applied forces [F_{x} F_{z}]^{T }are in a system defined as follows:
*x*-axis is in the direction of vehicle velocity relative to air,
*z*-axis is upward, and *y*-axis completes the
right-handed frame. They are functions of lift (*L*), drag
(*D*), thrust (*T*), weight
(*W*), flight path angle (*γ*), angle of attack
(*α*), and bank angle (*μ*).

$$\begin{array}{l}{F}_{z}=(L+T\mathrm{sin}\alpha )\mathrm{cos}\mu -W\mathrm{cos}\gamma \\ {F}_{x}=T\mathrm{cos}\alpha -D-W\mathrm{sin}\gamma \end{array}$$

4th Order Point Mass (Longitudinal) | 6th Order Point Mass (Coordinated Flight) | 6th Order Point Mass Forces (Coordinated Flight)