This paper addresses the boost and ascent trajectory design and guidance problem for rocket launched supersonic aircraft. Based on the typical upper and lower bounds of dynamic pressure for scramjet engine powered aircraft, the corresponding altitude-velocity bound profiles are obtained. For the boost phase trajectory, the angle of attack (AOA) is chosen as control variable and expressed in parametric form, the nominal profiles for the lowest and highest initial ground altitudes are designed by solving nonlinear equations generated by numerical integration, and the nominal boost trajectory profiles for varied initial ground altitude are obtained by combination of these two profiles. For the scramjet powered ascent phase, AOA and equivalent ratio are chosen as control variables, by using the lower and upper velocity-altitude profiles, and based on a linear acceleration assumption, a feasible nominal ascent trajectory design method is presented. Based on the designed nominal profiles and control variables, a feedback control guidance approach is proposed for tracking and control of the entire perturbed ascent trajectory. Numerical simulation results for a test aircraft are provided, demonstrating the effectiveness of the proposed methods.
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