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A review is presented of low-noise airplanes designed for operation in the 1980 time period. Aircraft with parametric engines covering a range of fan pressure ratios and noise levels were developed conceptually under contract with NASA Advanced Concepts and Missions Division, supported by the NASA Lewis Research Center contracts for the Quiet Clean STOL Experimental Engine (QCSEE) Study Program. Powered-lift concepts included externally blown flap, augmentor wing, internally blown flap, and over-the-wing upper surface blowing. Performance, sizing, and costs are described for 148 passenger airplanes with design field length varying from 2000-4000 ft. Techniques for reducing noise are evaluated in terms of aircraft performance, weight, and cost; experimental data on decayer nozzles are presented and assessed with respect to effectiveness in exhaust noise reduction and aircraft performance penalties.

This paper describes the results of parametric design studies of the application of filamentary composite materials in the structure of high-subsonic-speed transport aircraft. System costs and weight savings are presented as a function of percent utilization of composite materials from zero to 80%. The weight savings potential of composites for direct material substitution and for resized aircraft show gains of up to 25 and 50%, respectively. The state-of-the-art in structural design, analysis, fabrication, and test is discussed. Structural design concepts are shown and test validation is given, along with cost analyses.

It is hypothesized that the potential value of powered lift may be greater for transport applications requiring RTOL and CTOL field lengths than for those requiring STOL performance. Thus, it is implied that powered lift can be applied effectively to aircraft designed for medium and long haul, as well as short haul. This premise has been reached on the basis of observed trends in direct operating cost, mission fuel consumption, and, most significantly, community noise footprint areas for both powered lift and conventional mechanical flap configurations. Some pertinent results from recent NASA-sponsored configuration design and system studies for quiet short haul and fuel-conservative aircraft are discussed, and further data are developed to explore the potential value of incorporating powered lift concepts in advanced aircraft designs for medium and long haul applications.

The frequent use of large transport aircraft on soft and rough airfields in or near battle zones requires that they be fitted with landing gears having increased capability for ground flotation and shock absorption. Design and parametric studies of aircraft landing gears show feasible approaches to the problems associated with soft and rough airfields. Landing gear concepts, analytical methods, and design parameters are presented for airplanes of 110,000–750,000 lb gross weight. Landing gear weights, sizes, and configurations are compared, and their soft and rough field capabilities are evaluated. Structural and dynamic aspects of rough field operations are discussed for bare soil fields and for fields covered with landing mats.

The C-5A propulsion system installation is described and discussed. Induction system, exhaust system, and thrust reverser configurations define the general nacelle concepts. Installation features of the various subsystems, including the air bleed, engine starting, and fire protection systems are discussed. Installation requirements which are influenced by the high bypass ratio, short duct, turbofan engine configuration are noted and discussed. Where significant, comparison is made with requirements for an assumed long duct configuration. Special emphasis is placed on cooling and venting. Accessibility and maintenance features are also highlighted in the discussions.

The aviation community is preparing to cope with large increases in air traffic and operating costs projected during the next decade, while continuing to maintain safe operating procedures and methods. To do this the Federal Aviation Administration is updating and improving air traffic control systems, while the airframers and operators are developing methods to reduce aircraft weight, fly fuel efficient profiles, and optimize crew complements. New technologies are being exploited, efficient crew systems are being designed, and full-mission flight simulators are being constructed to test the systems in a near-real-world environment. One primary concern of the designers, operators, and certifiers is the determination of the proper amount and type of automation in crew systems. Lockheed-Georgia Company, in conjunction with the National Aeronautics and Space Administration, has developed a candidate conceptual design for a 1995 flight station.

A graphite/epoxy composite rudder for the Gulfstream Aerospace G-III executive jet aircraft was designed, tested and certified by the Lockheed-Georgia Company. The design replaces a conventional skin-stiffened aluminum structure, and achieves a 50% increase in acoustic fatigue life with a 22% weight savings. The design incorporates an innovative rib cap design with greatly improved fatigue and damage resistance over conventional composite rib cap designs. Details of the design as well as the FAA certification plan are presented in this paper. The certification plan, based on FAA Advisory Circular No. 20-107 (Reference 1), outlined the design details as well as all requirements for element, component and full-scale testing. Both static and acoustic fatigue element and component tests were conducted, with applied impact damage representive of initially detectable damage levels that could be incurred in the rudder skins.

This paper describes the comprehensive database developed by the Lockheed Aeronautical Systems Company which underscores (he critical mission needs for an Advanced Tactical Transport (ATT). A unique process was used to substantiate that an ATT must have the capability to: Deliver Army maneuver units and their fire support systems that weigh up to 55,000 lb. Operate on hot days, at night, or in bad weather from unpaved runways less than 2000 ft. In length at elevations greater than 4000 ft. Operate routinely within 20 nm of enemy Sines, and occasionally over enemy territory, and have improved survivability features. Accomplish multiple unrefueled sorties with total distances up to 1500 nm. Design implications, considering six specific alternative concepts, are discussed in terms of relative mission effectiveness, cost, supportability, survivability, technology and system programmatics.