10,314 research outputs found

    Pilot dynamics for instrument approach tasks: Full panel multiloop and flight director operations

    Get PDF
    Measurements and interpretations of single and mutiloop pilot response properties during simulated instrument approach are presented. Pilot subjects flew Category 2-like ILS approaches in a fixed base DC-8 simulaton. A conventional instrument panel and controls were used, with simulated vertical gust and glide slope beam bend forcing functions. Reduced and interpreted pilot describing functions and remmant are given for pitch attitude, flight director, and multiloop (longitudinal) control tasks. The response data are correlated with simultaneously recorded eye scanning statistics, previously reported in NASA CR-1535. The resulting combined response and scanning data and their interpretations provide a basis for validating and extending the theory of manual control displays

    Mach 5 inlet CFD and experimental results

    Get PDF
    An experimental research program was conducted in the NASA Lewis Research Center 10 x 10 ft supersonic wind tunnel. The 2-D inlet model was designed to study the Mach 3.0 to 5.0 speed range for an over-under turbojet plus ramjet propulsion system. The model was extensively instrumented to provide both analytical code validation data as well as inlet performance information. Support studies for the program include flow field predictions with both 3-D parabolized Navier-Stokes (PNS) and 3-D full Navier-Stokes (FNS) analytical codes. Analytical predictions and experimental results are compared

    Development of reclaimed potable water quality criteria

    Get PDF
    In order to minimize launch requirements necessary to meet the demands of long-term spaceflight, NASA will reuse water reclaimed from various on-board sources including urine, feces, wash water and humidity condensate. Development of reclamation systems requires the promulgation of water quality standards for potable reuse of the reclaimed water. Existing standards for domestic U.S. potable water consumption were developed, but do not consider the peculiar problems associated with the potable reuse of recycled water. An effort was made to: (1) define a protocol by which comprehensive reclaimed water potability/palatability criteria can be established and updated; and (2) continue the effort to characterize the organic content of reclaimed water in the Regenerative Life Support Evaluation

    Empirical source noise prediction method with application to subsonic coaxial jet mixing noise

    Get PDF
    A general empirical method, developed for source noise predictions, uses tensor splines to represent the dependence of the acoustic field on frequency and direction and Taylor's series to represent the dependence on source state parameters. The method is applied to prediction of mixing noise from subsonic circular and coaxial jets. A noise data base of 1/3-octave-band sound pressure levels (SPL's) from 540 tests was gathered from three countries: United States, United Kingdom, and France. The SPL's depend on seven variables: frequency, polar direction angle, and five source state parameters: inner and outer nozzle pressure ratios, inner and outer stream total temperatures, and nozzle area ratio. A least-squares seven-dimensional curve fit defines a table of constants which is used for the prediction method. The resulting prediction has a mean error of 0 dB and a standard deviation of 1.2 dB. The prediction method is used to search for a coaxial jet which has the greatest coaxial noise benefit as compared with an equivalent single jet. It is found that benefits of about 6 dB are possible

    The measurement of driver describing functions in simulated steering control tasks

    Get PDF
    Measurements of driver describing functions in steering control tasks have been made using a driving simulator. The task was to regulate against a random crosswind gust input on a straight roadway, in order to stay in the center of the lane. Although driving is a multiloop task in general, the forcing function and situation were configured so that an inner-loop visual cue feedback of heading angle of heading rate would dominate, and the driver's response was interpreted to be primarily single-loop. The driver describing functions were measured using an STI describing function analyzer. Three replications for each subject showed good repeatability within a subject. There were some intersubject differences as expected, but the crossover frequencies, effective time delays, and stability margins were generally consistent with the prior data and models for similar manual control tasks. The results further confirm the feasibility of measuring human operator response properties in nominal control tasks with full (real-world) visual field displays

    Pilot dynamic response to sudden flight control system failures and implications for design

    Get PDF
    Pilot dynamic response to sudden flight control system failure

    Assessing the Quality of Democracy: A Practical Guide

    Get PDF

    Principles for the design of advanced flight director systems based on the theory of manual control displays

    Get PDF
    Design and development of flight director systems based on theory of manual control display

    Who Cares About the Craft Apprentice? A report of a study of the attitudes to further education of 2,000 Scottish craft apprentices

    Get PDF
    The recent publication by the Scottish Council for Research in Education of ";A Day Off Work?";, concentrates on a description of the attitudes towards further education of some 2000 craft apprentices in Central Scotland. The data was collected during 1968 and 1969 by means of questionnaire, interview and attitude scale and in this article a brief summary will be given mainly in terms of each category of student rather than each source of data. The categories of students involved can be considered in terms of the craft course attended or the mode of attendance. Respondents were drawn from the City and Guilds Craft courses in Catering, Electrical Installation Work, Mechanical Engineering, Fabrication Engineering and Carpentry and Joinery, and over 200 of these followed full-time or block release courses during the investigation
    corecore