Aircraft Stability Analysis Including Unsteady Aerodynamic Effects

24Nwiα2( x ) = a + b x c xC +wiw1 w11iw1wiNwiα&2( x ) = a + b x c xC +wiw2 w2wi w2wi(1-23)where a , b , and c are constants to be identified from experimental results.wjwjwj► Normal Force on Left and Right Horizontal TailsThe horizontal tail is modeled in a similar way to the wing, bydxτdttit1 + xti= xt0 ti−( α τ & α )t 2tix t 0( α − τ & α )titi2ti1=1+expt ti t*( −σ( α −α)(1-24)CNti= CNti0+ CNtiα( x )tiα + CtiNtiα22( x ) α + C ( x )titiNti & αti& αtiSubscript “t” stands for horizontal tail, and the left and right horizontal tails arerepresented respectively by i = l, r.Not considering the aerodynamic interference from the wing, the local angle of attack atthe left and right horizontal tail panels is written as,αtl= tan−1⎛⎜ tanθ0cosφ−⎝VT⎞tφ⎟cosθ0⎠l & (1-25)αt r= tan−1⎛⎜ tanθ0cosφ+⎝VTl & ⎞tφ⎟cosθ0⎠where l t is the distance of the selected location on the horizontal tail panel from theaircraft longitudinal axis, also another parameter to be identified.The aerodynamic derivatives in Eq. (1-24) are, like the wing, modeled by quadraticpolynomials of the internal flow state variable as