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Future aircraft turbine engines, both commercial and military, must be able to accommodate expected increased levels of steady-state and dynamic engine-face distortion. The current approach of incorporating sufficient design stall margin to tolerate these increased levels of distortion would significantly reduce performance. The High Stability Engine Control (HISTEC) program has developed technologies for an advanced, integrated engine control system that uses measurement-based estimates of distortion to enhance engine stability. The resulting distortion tolerant control reduces the required design stall margin, with a corresponding increase in performance and/or decrease in fuel burn. The HISTEC concept was successfully flight demonstrated on the F-15 ACTIVE aircraft during the summer of 1997. The flight demonstration was planned and carried out in two parts, the first to show distortion estimation, and the second to show distortion accommodation.

Avionics air utilizes a distributed system architecture to provide air cooling and air circulation for fire detection in non–habitable Space Station Freedom Fire Detection and Suppression (FDS) zones (racks, standoffs, and endcones). The distributed avionics air architecture utilizes dedicated hardware located within each zone to support the zone specific needs. The avionics air hardware is defined as two unique packages. The Avionics Air Assembly (AAA) supporting avionics air cooling includes a selectable speed fan, heat exchanger, smoke detector, and firmware controller. The Circulation Fan Assembly (CFA) supporting avionics air circulation includes a fixed speed fan and smoke detector.

International Space Station includes a Joint Airlock in the U. S. on-orbit segment to support U. S. and Russian extravehicular activity (EVA). In this plan, the U. S. Extravehicular Mobility Unit (EMU) and the Russian Orlan-M spacesuit system share a common vehicle water coolant loop. Since the two spacesuit systems use different biocide additives and contain different non-metallic materials in their respective cooling water loops, steps are being taken to insure that no deleterious effects occur due to the mixing of Orlan-M and EMU coolant water. This paper describes the activities of the Russian and U.S. International Space Station and EVA teams to understand the implications of using both countries' EVA systems in such a deeply interconnected manner. The paper discusses a current U.S. test program and Russian analyses, and presents results to-date in an ongoing issue.