6th Order Point Mass Forces (Coordinated Flight)

Calculate forces used by sixth-order point mass in coordinated flight

Library

Equations of Motion/Point Mass

Description

The 6th Order Point Mass Forces (Coordinated Flight) block calculates the applied forces for a single point mass or multiple point masses.

The applied forces [Fx Fy Fh]T are in a system is defined by x-axis in the direction of vehicle velocity relative to air, z-axis is upwards and y-axis completes the right-handed frame and are functions of lift (L), drag (D), thrust (T), weight (W), flight path angle (γ), angle of attack (α), and bank angle (μ).

Fx=TcosαDWsinγFγ=(L+Tsinα)sinμFz=(L+Tsinα)cosμWcosγ

Dialog Box

Inputs and Outputs

InputDimension TypeDescription

First

 Contains the lift in units of force.

Second

 Contains the drag in units of force.

Third

 Contains the weight in units of force.

Fourth

 Contains the thrust in units of force.

Fifth

 Contains the flight path angle in radians.

Sixth

 Contains the bank angle in radians.

Seventh

 Contains the angle of attack in radians.

OutputDimension TypeDescription

First

 Contains the force in x-axis in units of force.

Second

 Contains the force in y-axis in units of force.

Third

 Contains the force in z-axis in units of force.

Assumptions and Limitations

The block assumes that there is fully coordinated flight, i.e., there is no side force (wind axes) and sideslip is always zero.

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

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