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Current methods of life cycle assessment (LCA) include input-output (IO) models and process-based LCA. These methods either require excessive effort and time to reach a conclusion (process LCA) or do not adequately model how a change in a product's design will affect the environmental footprint (IO LCA). A variation of process-based LCA developed specifically for aircraft is presented in this study. A tool implementing this LCA, “qUWick,” is rapid and easily applicable to multi-disciplinary design optimization of aircraft. Models developed for the material production, manufacturing, usage, and end-of-life of an aircraft are examined. Outputs of qUWick are discussed for future air vehicles. When compared to process LCAs with similar boundaries, qUWick gives similar results, however qUWick models several stages of an aircraft's life cycle more accurately than other aircraft process-based LCAs.

One of the most common damages occurred found on commercial airframes are dents and gouges. The usual repair for these damages includes installation of metallic doublers with rivets or with hi-loks. Sometimes these doublers are of complex design, because of multiple angles of the original damaged skin. Many times the damages are in hard to reach areas. In these cases the traditional metallic doubler repairs are not only time consuming and but also expensive. As the numerous holes are be drilled through the original structure, its fatigue life is adversely affected. For airline operators, time is valuable and they cannot afford to lose revenue by spending longer time for repairs. The use of bonded composite doublers offers the airframe manufacturers and aircraft repair facilities an alternative repair process that alleviates the abovementioned concerns.

Some of the common methods of reliability prediction utilizing calendar or lot size dependence and various "k" factors for complexity, end use, product family, and environment are briefly reviewed. These techniques, although sometimes accurate and simple, do not provide adequate reliability tradeoff information and do not fully treat the effects of vendor variability and improvements in the state-of-the-art. From these techniques it is frequently difficult to understand causes of observed failure rates and to determine what can be done to achieve cost-effective reliability. One method of alleviating these objections is to derive a model based on microcircuit failure mode and mechanism knowledge. The current status of microcircuit failure knowledge is reviewed. Considerable use is made of data which has been acquired at very high stress levels and the relationship between this data and end use data is discussed.

Over the next twenty years, the role and contributions of successfully managed projects will continue to grow in importance to aerospace organizations, especially considering the demands of emerging markets. The accompanying challenges will be how to effectively reduce product and process cost where known (incremental) and unknown (transformational) technological innovation is required. Managing Aerospace Projects brings together ten seminal SAE technical papers that support the vision of a more holistic and integrated approach to highly complex projects. Using the concept of project management levers, Dr.