Mars Pathfinder flight system design and implementation

This paper describes the system architecture, design and implementation highlights for the Mars Pathfinder flight system scheduled to land on the surface of Mars on July 4, 1997. Mars Pathfinder is one of the new series of small, challenging missions doing significant science/engineering on a fast schedule and cost capped budget. The Mars Pathfinder spacecraft is actually three spacecraft: cruise stage, entry vehicle and lander. The cruise stage carries the entry and lander vehicles to Mars and is jettisoned prior to entry. The entry vehicle, including aeroshell, parachute and deceleration rockets, protects the lander during the direct entry and reduces its velocity from 7.6 to 0 km/s in stages during the 5 minute entry sequence. The lander's touchdown is softened by airbags which are retracted once stopped on the surface. The lander then uprights itself opens up fully and begins surface operations including deploying its camera and rover. The project is 2 years into its 3 year development cycle with most flight hardware delivered and in system test. This paper overviews the mission design, system architecture and configuration. Descriptions of key subsystems are given, including the entry, descent and landing system elements. The implementation approach is discussed from the point of view of the new ways of doing business needed to accomplish this challenging mission within the schedule and cost constraints.