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A family of standardized avionics enclosures has designed, fabricated and tested. These enclosures accommodate Standard Avionics Module circuit cards which utilize aluminum base plates and are cooled by conduction to their mounting guiderails in the enclosure. The guiderails incorporate high performance module clamps and state-of-the-art brazed-fin heat exchangers for air cooling. The enclosures are designed to be cooled by air delivered from an aircraft environmental control system. Cooling effectiveness and enclosure thermal performance have been determined by laboratory tests. Typically, the enclosures provide 85°C (185°F) module edge temperatures while operating with 27°C (80°F) cooling air in a 71°C (160°F) ambient environment. With an operating pressure loss of 374 Pa (1.5 inches of water), their outlet cooling air temperature approaches 71°C (160°F). This results in cooling effectiveness of about 22.7 g/s (3 lb/min) of cooling air per kW.

A novel cooling system, utilizing two-phase thermosyphon principles, has been developed for temperature control of the Boeing Jetfoil's night vision system. Analyses and tests conducted on this unit have shown that it can replace a current single-phase, forced liquid loop with minimal thermal penalty. In addition, the two-phase system is considerably lighter, and much quieter than the existing system.

A digital computer was used to control an augmented turbofan engine and its inlet on a supersonic fighter. A brief summary of the system configuration and performance provides the background for remarks on the development of the system. Throughout the program a free flowing interchange of ideas, design, and test data was maintained among three major contractors and three Government facilities, aiding in the integration process. Particular emphasis is placed on: The role of simulation in system development, Software development and configuration control, Adaptation of the propulsion control system to a series of test facilities. Based on the experience acquired in the successful completion of the program, conclusions relevant to future engine/airframe development are drawn -- digital electronic engine controls are practical and essential for the fully integrated aircraft of the future.

Future large spacecraft such as the Space Station will have high power dissipations and long heat transport distances. The combination of these two requirements dictate the need for a new heat transport technology. NASA-JSC has developed the concept of a two phase thermal bus in which the working fluid is evaporated at the heat collection site and is condensed at the heat rejection site. This provides a nearly isothermal system at lower pumping powers than current single phase systems. Boeing has developed a two-phase thermal bus testbed using ammonia working fluid. This testbed uses a Sundstrand rotary fluid management device (RFMD) to provide fluid pumping and liquid-vapor phase management. Overall heat transport capacity is 25 kW. This internally funded testbed is being used for thermal bus heat exchanger characterization and critical component life tests in an ammonia environment. Currently, the testbed has been assembled, proof-pressure tested, leak tested, and checked out.