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Several designs for flight controllers for jet transports were developed to improve panel visibility and pilot comfort. The designs were rated by a panel of 12 pilot-evaluators. Three of the designs—Dual Side-Arm, Yoke with a Vernier Handle, and Circumferential Drive with a Vernier Handle—met with sufficiently high acceptance that their further development and evaluation appears warranted. The issues of gaining acceptance, of obtaining judgments from appropriate evaluators, and of the need for further testing in dynamic flight simulators are discussed.

The many large-scale aerospace simulation facilities now available offer considerable potential for the generation of data on human performance that can be used in systems engineering design efforts. To realize this potential requires an understanding of the methodological limitations imposed by the basic characteristics of human performance, the application of efficient organizational techniques, and the development of more efficient techniques of experiment planning, design, and execution.

The purpose of this paper is: (1) To review the rationale of measuring operator workload in terms of auxiliary, or secondary task performance scores; (2) To summarize the important characteristics of suitable loading tasks; (3) To describe several loading tasks which have been used or which are potentially useful; and(4) To suggest the development of a set of standardized tasks which would be useful in obtaining more nearly comparable measures over a wide range of primary tasks.

Gap-detection thresholds and working-level preferences were determined for one standard and three experimental high-contrast cathode-ray tubes under four levels of ambient illumination, 100, 1,000, 5,000, and 10,000 ft.-c.; two angles of incidence, 30 and 60°; and two angles of regard, 0 and −45° Trace brightnesses required to perform the visual tasks were primarily a function of the reflectances and resulting background brightnesses of the cathode-ray-tube faces. The results of this study are related to classical psychophysical data on brightness discrimination, earlier work on "masking luminance" for rador displays, and a recent study on visual performance using electroluminescent displays under high ambient illumination.

The purpose of this study was to determine the influence of friction and inertia levels on the "feel" of rotary controls. Detection thresholds for changes in friction and inertia were determined and found to be about 10 to 20 per cent of the initial values. Preference ratings obtained for various combinations of friction and inertia increased as a function of inertia level and decreased as a function of friction level. Preferences for viscous friction were greater than for stick-slip friction. Psychophysical evaluations such as these are related to customer acceptance factors and provide a useful supplement to purely functional design criteria.

An apparatus and a method for validating estimates of performance time and reliability against empirical measures of human performance time and reliability are described. Measures of performance time were obtained on five tasks and were correlated with estimates of performance times obtained from eight judges in a previous study. Median observed and estimated performance times were highly correlated (r = .98, p<.01). Estimates of maximum performance time corresponded to the 95th to 100th percentiles of the observed distribution of performance time, but estimates of minimum performance time were high and scattered over the lower percentiles. The significant validity coefficient suggests the feasibility of using estimates of performance time, at least for some simple tasks, in system-analytic models when empirical data are lacking and are too expensive to obtain.

This paper assumes increasing use of analytical models in system design. Some characteristics of such models and requirements for human performance data compatible with them are discussed. Methods of obtaining human performance data for use in design models are considered. The use of expert judges to generate performance measures is reviewed. Two new studies are reported in support of the proposition that expert judgments may offer a practical method of obtaining performance measure with potentially wide application in analytical modeling efforts.