System Theoretic Framework for Assuring Safety and Dependability of Highly Integrated Aero Engine Control Systems

The development of complex, safety-critical systems for aero-engine control is subject to the, often competing, demands for higher safety and reduced development cost. Although the commercial aerospace industry has a general good safety record, and has placed much emphasis on process improvement within a strong safety culture, there continues to be a large number of design and requirements errors found during development and after entry into service. The thesis assesses current system safety practice within the aero engine control system industry, including international standards, and reviews the current practice against the research at MIT by Professor Nancy Leveson. The thesis focuses in particular on software safety as this is the area that has proven most challenging and most likely to experience high costs. The particular research topics reviewed are Intent Specifications, the System Theoretic Accident Modeling and Processes (STAMP) technique, and requirements completeness criteria. Research shows that many problems arise from requirements and design errors rather than component failures