NASA Guidelines and Standards. System-Level Software V&V .The Independence of IV&V. Software Safety Standards . Software Safety Procedures. Personnel. System-Safety Organizational Roles and Responsibilities .The Role of Headquarters S&MQ and the Center SR&QA Offices . Documenting the Process. The Role of Headquarters S&MQ and the Center SR&QA Offices. Community Responsibility . Policies, Guidelines, and Enforcement . Final Thoughts And Future Considerations.Summary ( class version by Jun Wu ) An Assessment of Space Shuttle Flight Software Development Processes The space shuttle is one of the most complex engineering projects ever attemptedby humans. It has a very sophisticated system to control the wide variety of aerodynamic actuators and reaction-control system jets that are used to maintain the required atmospheric and on-orbit flight profiles. This highly complicated, interconnected digital control system could not work without the software that is loaded into the on-board computers during the various phases of a shuttle mission. In early 1991, the National Aeronautics and Space Administration's (NASA's) Office of Space Flight commissioned the Aeronautics and Space Engineering Board (ASEB) of the National Research Council (NRC) to investigate the adequacy of the current process by which NASA develops and verifies changes and updates to the Space Shuttle flight software. The Committee for Review of Oversight Mechanisms for Space Shuttle Flight Software Processes (hereafter, the Committee) was convened in January 1992 to accomplish the following tasks : - Review the entire flight software development process from the initial requirements definition phase to final implementation, including object code buildand final machine loading. - Review and critique NASA's independent verification and validation process and mechanisms, including NASA's established software development and testing standards. - Determine the acceptability and adequacy of the complete flight software development process, including the embedded validation and verification processes through comparison with (1) generally accepted industry practices, and(2) generally accepted Department of Defense and/or other government practices (comparing NASA's program with organizations and projects having similar volumes of software development, software maturity, complexity, criticality, lines of code, and national standards). - Consider whether independent verification and validation should continue. The main part of this report outline the committee’s findings, conclusions and corresponding recommendations in below area: NASA Guidelines and Standards. System-Level Software V&V .The Independence of IV&V. Software Safety Standards . Software Safety Procedures. Personnel. System-Safety Organizational Roles and Responsibilities .The Role of Headquarters S&MQ and the Center SR&QA Offices . Documenting the Process. The Role of Headquarters S&MQ and the Center SR&QA Offices. Community Responsibility. Policies, Guidelines, and Enforcement . Final Thoughts And Future Considerations. After hearing presentations from the Shuttle Program Office and their various contractors, and after reviewing the extensive documentation they provided, the Committee concluded that: the current IV&V process is necessary to maintain NASA's stringent safety and quality requirements for man-rated vehicles. Therefore, the Committee does not support NASA's plan to eliminate funding for the IV&V effort in fiscal year 1993. The Committee believes that the Space Shuttle software development process is not adequate without IV&V and that elimination of IV&V as currently practiced will adversely affect the overall quality and safety of the software, both now and in the future.. ASA Guidelines and