The dynamic pressure at the vertical tail refers to the aerodynamic force exerted by the air on the tail surfaces of an aircraft during its motion. It is a measure of the airspeed-related impact on the tail and plays a crucial role in determining the aerodynamic forces and moments that affect the stability and control of the aircraft. As dynamic pressure increases, the true airspeed changes, impacting the aircraft’s yawing behavior. The formula to calculate dynamic pressure as follows:
Where:
- S is the wing area in m2.
- b is the wingspan in m.
- Qw is the Wing dynamic pressure in Pa.
- Cn is the  Yawing moment coefficient
- lv is the Vertical tail moment arm in m.
- Sv is the Vertical tail area in m2.
- Cv is the Vertical tail Lift curve slope in 1/rad.
- β is the Sideslip angle in radian.
- σ is the Sidewash angle in radian.