doi:10.1016/j.asr.2025.07.017engGutierrez de Alba, José DavidTresaco, EvaMortari, DanieleA study on an optimal analytical and an accurate algorithmic landing techniquesART-2025-144899Landing trajectory optimization is a fundamental challenge in aerospace engineering, traditionally approached by optimal control problem formulation. In practice, for Earth landing, the vehicle is subject to strongly non-linear perturbations, such as drag, wind, and gravity. Indirect control methods cannot deal with these problems, leading to large errors, while direct methods require high computation times when perturbations are not continuous. Thus, in this work, we propose a hybrid algorithm to approximate the solution of nonlinear optimization problems, based on the iteration of the indirect control analytical solution of the non-autonomous linear problem. The algorithm’s performance has been studied for the problem of landing rockets on the Earth’s surface and compared with a standard boundary value problem solver. The results show that the proposed algorithm tolerates strong discontinuous perturbations, with very small landing error and computation time.2025http://zaguan.unizar.es/record/16226810.1016/j.asr.2025.07.017http://zaguan.unizar.es/record/162268oai:zaguan.unizar.es:162268info:eu-repo/grantAgreement/ES/MICINN/PID2020-117066GB-I00info:eu-repo/grantAgreement/ES/MICINN PRE2021-099561Advances in Space Research 76, 5 (2025), 3098-3108byhttps://creativecommons.org/licenses/by/4.0/deed.esinfo:eu-repo/semantics/openAccess