Flight Mechanics Feasibility Assessment for Co-Delivery of Direct-Entry Probe and Aerocapture Orbiter

Abstract

The co-delivery of a direct-entry probe and an aerocapture orbiter from a single atmospheric entry state is a novel way to include ride-along probes or orbiters on interplanetary missions. This is made possible through combining two technologies: low-cost small satellites and aerocapture. This study investigates the feasibility of this co-delivery method from a flight-mechanics perspective. The availability of direct-entry and aerocapture trajectories from a single entry flight-path angle is assessed for a large range of feasible ballistic coefficients at Earth, Mars, Venus, Titan, and Neptune. Apoapsis altitude, peak heat flux, total heat load, and peak g-load are also quantified across this trade space. A representative scenario implementing closed-loop guidance is presented for a proof of concept, and the trajectory dispersions due to relevant uncertainties are quantified in a Monte Carlo analysis. Passive ballistic impactor or penetrator probes as a secondary mission with a primary lift-modulated aerocapture orbiter is identified as the most promising configuration.