Comparison of autorotation and propulsive landing for planetary exploration

In the rapidly evolving field of space exploration, the focus lies not only on enhancing launch capabilities but also on improving landing technologies on Earth and other celestial bodies. Propellant-based systems currently dominate targeted landings since they allow a high degree of control in a variety of environments. While this enables high precision and hazard avoidance capabilities, these propulsion systems impose a significant mass penalty, particularly over longer distances. This work explores an alternative descent and landing method: autorotation, a well-established mechanism in helicopter emergency landings. Autorotation trades the propellant-based propulsion system for a rotor system that requires no fuel, allowing for substantial horizontal distance coverage with minimal mass impact. In this paper, its potential for missions on Earth, Mars, Titan, and Venus is analyzed, comparing its efficiency to traditional propulsive approaches. The results show that autorotation outperforms propulsion in most scenarios, offering a promising alternative even under conservative assumptions. These findings highlight the potential of autorotation as a viable, mass-efficient descent and landing method for future missions. • Autorotation can outperform propulsive systems for landing spacecraft. • Novel autorotation model and simulation for other planets. • Comparison of landing capabilities of autorotation and propulsion systems. • Autorotation shows feasibility for exploration missions; better in denser atmospheres.