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No greater contribution seems to exist for improving supersonic transport economics than by improving the state of the art of jet noise suppressors. Exact matching of thrust requirements for supersonic cruise, transonic acceleration, climb, and especially takeoff-climb is complex. The present design becomes an equivalent five-engine configuration, where the extra thrust is required to enable environmental levels of FAR Part 36 to be achieved. The added size is required first to allow for engine throttling during takeoff run to provide reduced exhaust velocity and exhaust gas temperature consistent with suppressor structural limits, and secondly to make up for suppressor losses at takeoff flight speeds. As the engine selection must be closely tied to airplane selection, substantiation of the 2.2-M airplane selection is described.

Douglas Aircraft Company (DAC) of Long Beach, California, uses a real-time development environment, the avionics evaluation facility (AEF), to develop new avionics systems for the MD-11 aircraft. The development environment includes a host computer, input/output (I/O) software/hardware interface, and avionics system. The I/O interface developed at DAC, the interface microcomputer system (IMS), is a highly developed, flexible, practical, reliable, and sophisticated system for interfacing the host computer to the avionics system. This paper describes the IMS from its historical background to its present configuration in the AEF environment.

The incorporation of divergent trailing-edge (DTE) technology into the design of a derivative wing is pres ented. The structural constraints imposed by the derivative approach will be reviewed with respect to their impact on the wing design. The predicted drag and buffet characteristics, derived using a combination of computational fluid dynamics (CFD) and empirically developed methods, are compared to wind tunnel measured characteristics. Calculated and measured results show a significant improvement in the performance of the derivative wing due to the integration of DTE airfoil technology.

Modern design practices for long-life aircraft and how they relate to the current aging aircraft fleet situation are presented. Concepts of the maintenance programs are also introduced along with means of modifying the program to protect the aircraft against the increased probability of fatigue and corrosion as the aircraft ages. Special programs by the manufacturer, such as extended fatigue testing and on-site aircraft evaluations, are discussed. The recent aging aircraft activities sponsored by the ATA and AIA are also examined.

The electromagnetic dent removal process removes dents from many aluminum structures where access is either limited to one surface (e.g., bonded aluminum honeycomb parts) or where access to the rear surface is restricted by equipment or other structures.

A combination of factors including market growth and engineering technology advancements in the next few years have raised the possibility of an economically and environmentally viable high-speed commercial transport (HSCT). McDonnell Douglas studies have found that the primary candidate for this application is a vehicle cruising at Mach 2.4. An engineering and environmentally conservative configuration cruising at Mach 1.6 is also being studied. The vehicle incorporates numerous advanced features including an airframe consisting of advanced composites and metals. Takeoff gross weights are on the order of 700,000 to 800,000 pounds for a design range of 5,500 nautical miles. Studies are focused on entry into service in the year 2005, with the authority to proceed with preliminary and full-scale development in 1998.

Future transport aircraft secondary power requirements can be expected to increase due to advancements that utilize additional pneumatic, hydraulic and electric power. This paper reviews the power requirement trends and suggests possible alternative approaches for future secondary power generation installations. Airline ideas and comments are solicited to enable early incorporation into technology development programs.

This paper examines the usefulness of the NASA Task Load Index (TLX), a multidimensional rating procedure, in subjectively assessing the overall aircrew workload. There is evidence that nothing is gained by using weighted averages from individual bipolar rating scales to generate a single rating for overall workload. A similar, reliable assessment can be developed from several of the individual bipolar rating scales. During a joint simulation study conducted by Douglas Aircraft Company and Boeing Commercial Airplanes, NASA-TLX scores were collected from pilots in simulated commercial transport operations. Both normal and emergency conditions were programmed to a Phase II certified B-727, six degree-of-freedom motion-base simulator. Correlation and factor analyses of the bipolar ratings were computed to determine the overlap of the different rating scales within the NASA-TLX.