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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.

The critical design weight environment necessary to optimize load-carrying efficiency of the C-5A was such that breakthroughs in technology were needed. One such breakthrough was beryllium brakes. From the discovery of beryllium in 1798 its advantages-as well as its disadvantages-were well known. These are discussed to indicate why beryllium was chosen as the brake heat sink material for the design configuration evolved. A review of current C-5A data is presented, including flight test experience, as well as expected life projection from limited normal operational experience. The re-use of beryllium elements, and cost effectiveness are also discussed. A consideration of the future use of beryllium is indicated, with the conclusion that it will become commonplace in the next decade.

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.

Tactical Airlifters in the battlefield of the future will be required to operate on unprepared or damaged runways in all weather conditions without navigational or landing aids. Lockheed is addressing technologies required for these missions in an independent research and development program using a highly modified commercial C-130 aircraft as the technology integration focal point - a “Flying Laboratory.” The HTTB Program addresses the major technology areas of advanced short takeoff and Sanding, survivability, advanced cockpit, and electronic systems. The Program goal is to develop systems to support autonomous operations into a 1500-foot landing area, up to and including a 50-foot obstacle at the runway threshold.

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.

From an analysis of a typical large airport and its growth problems, it is concluded that STOL aircraft systems are needed now-with or without high-speed ground transportation systems. It is also shown that the needed first-generation STOL aircraft can be in operation in 1975. These contemporary STOL aircraft will, however, be only a step in the evolution to improved aircraft of the future. The needs for technological improvements are discussed, and some new prospects in STOL technology are described.