Aerodynamic forces formulation for aircraft aeroservoelasticity studies

An important aspect of aeroservoelastic interactions studies is the common aerodynamic forces formulation for servo -control studies on rigid aircraft and for aeroelastic studies on flexible aircraft. Aerodynamic generalized forces are calculated for aeroelasticity studies on a flexible aircraft from purely oscillatory mot ion of each mode for a range of reduced frequencies and Mach numbers. Aerodynamic forces are calculated for servo -control studies on six degrees of freedom rigid aircraft by use of Newton’s equations of motion. For aeroservoelasticity studies, we replace a erodynamic forces calculated in aeroelasticity studies for rigid / control interactions with forces calculated by rigid body Newton’s theory for servo -control analysis. In aircraft stability and control analysis, we observe the dependency of small variatio ns on parameters defining aircraft’s motion around the trim point, such as linear and angular coordinates, velocities and accelerations. Calculation of forces implies calculation of longitudinal and lateral stability and control derivatives. The relationsh ip between generalized force coefficients in the inertial axis system and aircraft body axis non dimensional stability and control derivatives is here summarized. Longitudinal (symmetric mode) and lateral (anti -symmetric mode) stability and control coeffic ients are here calculated for the generalized stiffness and damping matrices.