The Flight Path Angle (FPA) is the angle between an aircraft’s velocity vector and the horizontal plane. It represents the trajectory of the aircraft in three-dimensional space. Positive Flight path angle indicates a climb, negative FPA denotes a descent, and zero Flight path angle corresponds to level flight. FPA is a crucial parameter for understanding an aircraft’s vertical movement during flight. The flight path angle formula is derived from the forces acting on gliding flight. The formula to calculate flight path angle is as follows:
Where:
- D is the Drag force in N,
- L is the Lift Force in N.