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In the early history of engineering, the engineer was an integrator of many technologies. With the advent of the digital computer in the mid 1950's this began to subtly change as the demands of implementing various analytical methods on digital computers tended to focus engineers on the analysis of a single discipline such as structural mechanics. This revolution in engineering practice is reaching maturity after almost 40 years of intensive research. For such fields as rigid body mechanics, structures, and fluid mechanics, computational methods exist which span a range from simple techniques to full implementations of the underlying field equations. This paper will argue that the remaining part of the revolution in engineering should refocus on the engineer as a generalist by using the computational techniques in a more integrated fashion. To accomplish this, work that needs to be carried out in several areas will be discussed.

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.