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In M.S. thesis #1, advantages of applying exergy-based analysis and optimization methods to the synthesis/design and operation of aircraft systems is demonstrated using a supersonic aircraft fighter flown over an entire mission. A first set of optimizations involving four objectives (two energy-based and two exergy-based) are performed with only propulsion and environmental control subsystem degrees of freedom. Losses for the airframe subsystem are not incorporated into the two exergy-based objectives. The results show that, as expected, all four objectives globally produce the same optimum vehicle. A second set of optimizations is then performed with airframe degrees of freedom. However, this time one of the exergy-based objectives incorporates airframe losses directly into the objective. The results are that this latter objective produces a significantly better optimum vehicle. Thus, an exergy-based approach is not only able to pinpoint where the greatest inefficiencies in the system occur but seems to produce a superior optimum vehicle as well by accounting for irreversibility losses in subsystems only indirectly tied to fuel usage. No studies to date of which we are aware demonstrate the technology through an entire mission in which multiple flight conditions and constraints are encountered. Consequently, in M.S. theses #2 and #3, a formal Mach 6 through Mach 10 flight envelope is explored which includes cruise, acceleration/climb, deceleration/descend and turn mission segments. An exergy approach to the vehicle synthesis/design, in which trade-offs between dissimilar technologies are observed, is proposed and measured against traditional energy-based methods of assessing highly integrated systems. The mission-level analysis provides much insight into the dynamics of mission-level hypersonic flight and demonstrates the usefulness of an exergy destruction minimization measure for highly integrated synthesis/design.

Research was conducted to determine the more important criteria that dot-matrix displays intended for use in aircraft cockpit environments should satisfy in order to be compatible with pilot visual perception and information cognition requirements. Techniques to process and display both rapidly time changing and moving numeric information are presented. The legibility performance of developmental programmable legend switch displays is described including the effect of and methods for masking the appearance of fingerprints. Information processing and display techniques for enhancing the appearance of dot-matrix imagery under both translation and rotation are introduced in association with the description as a result of testing developmental video and color dot-matrix displays are also provided. Inconsistencies encountered with existing military grey scale requirements and with the methods currently being developed to objectively describe colors were evaluated and described. No degradation in pilot performance attributable to the dot-matrix nature of the display media was revealed by the experiments conducted. The total number of picture elements (pixels) available to present information was assessed as being the criteria issue that is primarily responsible for establishing both the objective performance capabilities of dot-matrix displays and their aesthetic appeal.