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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.

Second generation, or toughened, epoxy resin systems are under consideration for use on a large composite primary structural part such as a wing. A method of evaluating the properties of these materials, while at the same time considering design, structural and manufacturing requirements has been developed. Processability requirements for toughened epoxy resin systems have been established. Cost efficient manufacturing methods, such as pultrusion, have been investigated and found to be a feasible production method for composite structure. The use of pultrusion as a fabrication method for partially staged parts to be co-cured at a later date is being evaluated.

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 high equipment investment cost of today's large transport aircraft, the high daily utilization desired or required for profitable operations, and the potential revenue losses associated with service interruptions make it mandatory for the manufacturer to take an active part in the early reduction and correction of service problems. The high investment, not only by the aircraft operators but also by the manufacturer, demands the establishment of a mutual participation team effort for early problem resolution. This paper deals with an aircraft manufacturer's approach to meeting this challenge. It discusses the accumulation and evaluation of service data, the investigations initiated to properly understand the problem, and the management procedures established to assure a safe and speedy problem resolution with a minimum of service interruption. Specific examples are used to illustrate the types of decisions reached.

Area Navigation Systems (RNAV), coupled with appropriate air traffic control techniques, promise to improve the movement of aircraft within the National Airspace System (NAS). These systems are based upon use of the NAS ground radio navigation aids by the airborne navigation receivers, and other sensors available in today's aircraft. The evolution and product development of airborne equipment for this purpose have been guided by airline and FAA operational needs. The airline industry, through its Air Transport Association (ATA) and Airline Electronic Engineering Committees (AEEC), is standardizing the requirements for three classes of equipment. These are: Mark I RNAV, simple, yet requiring considerable pilot manual operation; Mark II RNAV, virtually automatic, with new cathode-ray tube multi-function/navigation displays for the pilot; and Mark III (Mark 13) RNAV, based upon use of the self-contained inertial navigation systems presently installed in today's large jets.