Overview of the Crew Exploration Vehicle Parachute Assembly System (CPAS) Generation I Drogue and Pilot Development Test Results

Abstract

The Orion spacecraft is currently under development by NASA and Lockheed Martin. Previously known as the Crew Exploration Vehicle (CEV), Orion is the next generation spacecraft for human spaceflight. The Orion Crew Module (CM) resembles the Apollo capsule, but is much larger. Like Apollo, Orion will return to Earth under a parachute system. This parachute system is being designed by NASA, Jacobs Engineering, and Airborne Systems. The Generation I CPAS parachute system configuration consists of two mortar-deployed Drogue parachutes, three mortar-deployed Pilot parachutes, and three Pilot-deployed Main parachutes. A series of tests was planned and executed to test the CPAS Generation I Main parachutes individually, and a second series of tests was executed to analyze the effects of the Mains in a cluster configuration. These tests occurred between August 2007 and July 2008 at the US Army Yuma Proving Ground (YPG). The goal of each test was to determine the performance of the parachutes at the established test conditions. A variety of test techniques were used to establish the desired test conditions at parachute deployment. Prior to each flight, rigorous analyses were accomplished 1) to establish the validity of the test technique, 2) to establish sequencer timing, 3) to keep the predicted parachute loads within the parachute and hardware capability, and 4) to plan the test to operate within the required constraints of the range. Analysis tools included simulations such as the Decelerator Systems Simulation (DSS), an aircraft extraction tool Decelerator Systems Simulation Application (DSSA), Decelerator Dynamics (DCLDYN), a modified two degree of freedom version of DSS called DTV-Sim, and a landing footprint predictor tool (Sasquatch). After each test, the tools were used to reconstruct the parachute performance during the flight using the data gathered on-board and by the range. Reconstructions were used to update the existing parachute models/simulations for on-going development work. The performance parameters were found to be consistent between tests for the individual Main parachutes. Test techniques, preflight predictions, test instrumentation, reconstruction results and challenges, and a brief discussion of the lessons learned from each test will be presented.