Capstone design courses are intended to provide a culminating experience for senior undergraduate engineering majors. Universities vary in how they implement the instruction and implementation of the design process in their capstone courses. For example, many have a separate class in design methods, followed by a one-semester capstone course where teams work on a "design, build, test" project. Other institutions teach design methodology incorporated into the capstone design project in what is often a two-semester capstone sequence. In the cases where design methodology is incorporated into a two-semester capstone course, it is possible that this is the students' first extensive exposure to design methods and process. In that case, students may be experiencing methods such as "Customer Needs Analysis", "Functional Decomposition", "Concept Generation", "Concept Selection" and "Prototype Planning" for the first time. From a constructivist educational standpoint, it can be problematic for students to apply these design techniques for the first time on what is often a complex, real world capstone design problem. One solution to this problem is to incorporate a short design experience at the beginning of the two-semester capstone course. This can allow the students an initial experience with the design methods that can provide a "learning scaffold" for their implementation of the full suite of design methods over the course of a two-semester project. For the last three years, we have implemented three versions of a short, introductory design project (i.e. designette) in our twosemester capstone design sequence. In our uses of the designette project, the suite of five core design methods mentioned above were taught in an abbreviated form. However, in one year the designette lasted ten class hours, the next year's designette lasted 14 class hours, and this past year's project lasted seven class hours. The longest designette allowed for greater depth in the initial coverage of the methods and also provided greater time for prototyping and testing. Of course this was at the cost of consuming a greater percentage of the overall time allocated for the actual capstone design project. This paper reports on the implementation details of the designette projects, focusing in particular on advantages and disadvantages of the different implementations in the most recent years. Faculty and student feedback indicated that the use of the designette does increase student familiarity with the design methods. However, more subtle questions such as the number of lessons allocated for the designette and the depth of coverage of the design methods have much more complicated assessment results.

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Airframe structural components experience coupled load-environment spectra that are currently not captured in traditional damage-tolerant management approaches. The effect of incorporating fatigue crack growth kinetics relevant to high-altitude flight environments into LEFM-based predictions of fatigue progression for aluminum alloy 7075-T651 was quantitatively assessed for a variety of load-environment spectra using AFGROW. The results of this study demonstrated that in all conditions, the incorporation of high-altituderelevant growth kinetics enhanced the fatigue life predictions. However, the magnitude of the impact on the overall life is dependent upon the subtleties of the coupled load-environment spectrum, despite the fact that environmental effects are most potent in the near-threshold regime of the da/dN versus ΔK relationship. The potential impact to the structural integrity management community is discussed, and remaining challenges and opportunities are identified.

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