Aircraft Stability Analysis Including Unsteady Aerodynamic Effects

used to find the model parameters were published as a function of φ () t . For each fixedvalue of the wing pitch angle θ 0, the local sideslip angle time history βi() t can bedetermined through φ () t and ( t)i60α time-histories by using Eqs. (1-22) and (1-28),derived in Appendix A.2. However, for a general type of motion where the pitch angle isnot fixed, those relations are no longer valid.In this postulated model, the equations used to represent the unsteady aerodynamics forgeneral flight conditions in each panel of the airplane are:dxdydvidtidtidt() t() t() t===f1, iff2,i3,i( α , & α )i( φ , & φ )( φ , & φ)i(2-8)(2-9)(2-10)( x , y , α , & α , φ,& φ)C = g(2-11)N , i i i i iwhere the subscript i stands for each lifting panel, i.e., i = l (left) , r (right).The value of the normal force coefficient for the whole slender delta wing is found alsothrough Eq. (2-3).As shown in Section 1.1.6, we can calculate the rolling moment coefficient for theaircraft through Eq. (1-33), which in the particular case of the slender delta wing reducesto:ClN ll( φ) − C y ( φ)= C y(2-12)N rrwhere y (•)are the non-dimensional arms of the normal force coefficient with respect tothe longitudinal body axis, given by Eq. (2-9).