Entry Atmospheric Flight Control Authority Impacts on GNC and Trajectory Performance for Orion Exploration Flight Test 1

摘要

One of the key design objectives of NASA's Orion Exploration Flight Test 1 is to execute a guided entry trajectory demonstrating Guidance, Navigation, and Control (GN&C) capability. The focus of this paper is the flight control authority of the vehicle throughout the atmospheric entry flight to the target landing site and its impacts on GN&C, parachute deployment, and integrated performance. The vehicle's attitude control authority is obtained from thrusting 12 Reaction Control System (RCS) engines, with four engines to control yaw, four engines to control pitch, and four engines to control roll. The static and dynamic stability derivatives of the vehicle are determined to assess the inherent aerodynamic stability. The aerodynamic moments at various locations in the entry trajectory are calculated and compared to the available torque provided by the RCS. Interaction between the vehicle's RCS engine plumes and the aerodynamic conditions are considered to assess thruster effectiveness. This document presents an assessment of Orion's flight control authority and its effectiveness in controlling the vehicle during critical events in the atmospheric entry trajectory.