This paper illustrates the trajectory modeling of multistage rockets for both ascent and descent phases. The computation of solutions is performed by coupling a multiphase optimal-control problem formulation with a transcription performed via Radau pseudospectral methods. Four examples inspired by both historical rockets like the Saturn V, and modern reusable launch systems like the Falcon 9 demonstrate the feasibility of the proposed modeling approach for the rapid prototyping of valid reference solutions.
V. et al. (Fri,) studied this question.