Oscillation susceptibility analysis along the path of longitudinal flight equilibriums

Existence of oscillatory solutions along the path of longitudinal flight equilibriums of an unmanned aircraft, when the automatic flight control system fails

“…The simplified system of differential equations, which governs the motion around the center of mass in a longitudinal flight with constant forward velocity of a rigid aircraft, when the automatic flight control system is decoupled, is given by [9,12]:…”

“…The following proposition [9,12] addresses the existence of equilibrium states for the system (2.1). …”

“…Numerical results obtained in oscillation susceptibility analysis of the ALFLEX unmanned reentry vehicle, with decoupled flight control system, are reported in [9,10].…”

Existence of oscillatory solutions in longitudinal flight dynamics

“…A detailed description of how to derive system (1) from the general system of differential equations [17,18] which describes the motion around the center of gravity of a rigid aircraft, with respect to an xyz body-axis system, where xz is the plane of symmetry, has been presented in [12].…”

“…In [12,13], it has been shown that in a longitudinal flight with constant forward velocity, equilibria exist for the AD-MIRE aircraft and the ALFLEX reentry vehicle only if the elevator deflection δ e belongs to a closed and bounded interval J. When the elevator deflection is at the boundary of the interval J, a countable infinity of saddle-node bifurcation points is present.…”