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The use of interactive computer graphics for aircraft structural design is discussed. The software used is the Lockheed-California Company Computer-graphics Augmented Design and Manufacturing (CADAM)® system in conjunction with our inhouse Surface Design and Finite Element Model programs. Starting with the conceptual design on the CADAM system, configuration geometry is generated for use by analysis users, preliminary design, loft, and production design organizations. An example used to demonstrate the application of the system is the development of a smaller horizontal tail for L-1011 derivatives, under the sponsorship of the NASA Energy Efficient Transport Technology office. The increased productivity achieved by using the CADAM system is described.

The paper deals with the emerging and topical subject of All-Electric Aircraft in which the electric system in an advanced airplane serves all the functions and services normally supplied by multiple power systems, such as engine bleed air, hydraulics, pneumatics, and conventional type electric power systems. Engine starting is of particular interest because of its demands for special logistic and maintenance ground support. Military and commercial aircraft typically use pneumatic, cartridge, fuel/air (combustion) or monopropellant starting methods, so these must be replaced by electric starting. The trend of the advanced technology engines is towards high bypass and high compression ratios, making them increasingly sensitive to tapping the compressor airflow: The energy-efficient engine is, therefore, an important design consideration in the All-Electric Airplane.

The maintenance diagnostics problem is becoming more difficult as weapon systems, operational environments, and tactical requirements become more complex. Existing fighter aircraft have achieved greater than 95% built-in test (BIT) capability, but are experiencing high false removal rates due to fault detection/fault isolation (FD/FI> ambiguities. This paper will shows how to reduce the program risk by implementing testability features as front end requirements. Integrated Diagnostics activities are part of the design process to build testability and supportability into the weapon systems. By influencing the hardware/software design early in the program, a large payoff in logistics costs will result in the operational and support phase.

Commercial transport aircraft must be capable of operating worldwide; accordingly, a fuel of uniform and high quality must be available worldwide. Hydrogen is proposed as fuel for advanced design transport aircraft in the era subsequent to 1990 because of the problems of availability and cost forecast for conventional jet fuel derived from petroleum. The result of design studies to evaluate the feasibility, practicability, and potential advantages/disadvantages of using hydrogen as fuel in both subsonic and supersonic transport aircraft are summarized. The design requirements and characteristics of aircraft tank and fuel systems to satisfactorily contain and control liquid hydrogen fuel are described.