The change in force in the horizontal direction, often referred to as the “X-direction,” is related to the aerodynamic behavior of an aircraft’s drag due to changes in angle of attack and other parameters.
- is the change in force in the horizontal direction (newtons, N).
- is the dynamic pressure (pascals, Pa).
- is the reference area of the aircraft (square meters, m²).
- is the mass of the aircraft (kilograms, kg).
- is the equilibrium velocity (meters per second, m/s).
- is the coefficient of drag with respect to angle of attack ().
- is the coefficient of lift at equilibrium velocity (u).