Solid Rocket Motor Reliability and Historical Failure Modes Review

Reliability of solid rocket motors has steadily increased since the beginning of solid propulsion systems. Increased reliability of solid rocket motors has produced a 100 percent success rate in orbital space launched rocket systems in the United States over the past 20 years. Historical failures have been attributed to different components of these systems including nozzles, propellant, cases, joints, propellant/liner/insulation bonds, and insulation. Attribution to improvements in testing, nondestructive evaluation (NDE), materials, manufacturing, processes, technology, and analytical tools is indicated for the increased reliability of these systems. This paper includes the following: 1) reviews of trends in historical reliability of solid rocket motors, 2) identification of historical failures modes and their implications to modern systems, and 3) a brief summary review of approaches that have been developed to improve reliability.