Abstract: When a manned spacecraft lands with high horizontal velocity, the resulting excessive head-pelvis accelerationis harmful to the astronaut’s safety. The existing buffer seat makes use of a passive buffer mechanism system to alleviate the chest-back landing-impact loads; however, the focus of this article is to reduce the dangerous head-pelvis acceleration. A dynamic model of the titled elastic supporting buffer seat in reentry manned spacecraft is designed. The buffer characteristics of the seat alleviating the chest-back and head-pelvis impact loads are analyzed by the model for the reentry spacecraft at high multidirection impact velocities. The results of mathematic simulation indicate that the improved titled elastic supporting buffer seat is better than the existing gemel joint supporting buffer seat, because the proposed seat attenuates the impact of head-pelvis acceleration effectively without increasing chest-back impact acceleration. The rules of support angle, stiffness, and damper described in this article can provide good reference for the optimal design of the buffer seat.

Key words: manned spacecraft, titled impact, titled elastic supporting seat, chest-back loads, head-pelvis loads, landing