A COUPLED INTERPLANETARY - ENTRY, DESCENT AND LANDING TARGETING PROCEDURE

Abstract

In NASA's past, targeting to a Mars landing site has required iteration between the Entry, Descent and Landing (EDL) analysts at NASA Langley Research Center and the interplanetary navigators at the Jet Propulsion Laboratory (JPL). JPL would develop thousands of arrival states at Mars based on an assumed, constant entry flight path angle and down range angle from entry to landing. Langley would perform the EDL analysis using the arrival states from JPL. Feasible trajectories developed by Langley had varying flight path and down range angles over the entire launch/arrival window forcing an iteration of the trajectory design between JPL and Langley. The iteration process was inefficient, stretching out the design phase while introducing the possibility for error. The purpose of this study is to develop a method that calculates an interplanetary trajectory from Earth to Mars and seamlessly couples the tool with Langley's EDL analysis. The method will show a novel extension to current Lambert solution methods while incorporating a multiple revolution capability.