The composition of an aircraft technology portfolio in response to environmental impact goals is of paramount importance for present and future aeronautics. Characteristics of the portfolio selection problem are ideally addressed via multi-objective genetic algorithm optimization. Methodological and practical considerations of this approach are examined while generating meaningful insight specific to a set of aircraft technologies expected to mature over the coming decade. Results allow for a detailed characterization of the set of Pareto-optimal technology combinations in terms of its corners, underlying performance tradeoffs, and salient topological features. High-impact technologies are resolved in terms of their pervasiveness across solutions in regions of interest. Because relativevalued environmental objectives can be exploited by the optimizer, the analysis is repeated with absolute-valued analogs to examine how the choice of objectives in this respect can affect the selection of technologies. The effect of resource costs associated with each technology, additively compounded for technology combination solutions, is also examined in this context by expanding the method to include a resource constraint. Accordingly, general features of the Pareto frontier in the objective space are characterized for varying degrees of resource constraint stringency.