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The evaluation and evolution of direct jet lift V/STOL transport aircraft designs are discussed. The V/STOL transport design selected as an example is a lift-fan design that was evaluated as a candidate configuration for a possible future V/STOL research transport. The paper includes discussion of potential advanced V/STOL landing approach profiles as key design requirements for V/STOL aircraft, description and experimental results of an integrated propulsion/control system designed to achieve desired advanced V/STOL near-terminal operating capabilities, and results from evaluating V/STOL designs on piloted moving-base simulators. This paper discusses use of the piloted moving-base simulator as a design tool for evolving satisfactory V/STOL stabilization and propulsion/control systems. Included are problems and solutions identified during simulation of simultaneous decelerating/descent steep curved landing approaches under instrument flight conditions. Simulation results are also compared to flight results obtained with the DO-31 V/STOL research transport.

The ideal output characteristic required from an internal combustion engine for vehicle propulsion is constant power output over the working speed range, and the present conventional engine falls very far short of this. The paper describes the development of a diesel engine which is supercharged by a compressor driven by a differential gear in such a way that the boost, and therefore the output torque, increases with decrease in engine speed and which goes some way towards giving the desired output characteristic. The further step is described of including a hydraulic torque converter in the system so that automatic operation by a single pedal control can be achieved over the practical operating range of normal road vehicles. It is shown that the full operating range required by all normal vehicles can be obtained with a gearbox with two speeds only. The results of road tests on a truck with varying payloads are given and the fuel consumptions achieved are shown in comparison with the same engine in both its naturally aspirated and turbocharged forms. Notes are given on the component development and mechanical development of the engine necessary to achieve these results in a reliable way. Details are shown of possible production arrangements of differential gears and drive trains, one of which incorporates a hydraulic retarder which can be done cheaply and effectively. The paper concludes with a note on future developments and a summary of possible advantages.

The objective of this paper is to illustrate an interactive computer graphics program developed to simplify the creation of finite element data which will be used for computerized structural analysis. Three-dimensional, part definition data in the form of basic design lines in input to the program and displayed on a cathode ray tube, and then a structural engineer creates the finite element definition using various computer graphics techniques. The procedures involved are discussed in detail, as well as the advantages over the traditional manual approach to element generation.

Interactions between propulsion systems and flight controls have emerged as a major control problem on supersonic cruise aircraft. This paper describes the nature and causes of these interactions and the approaches to predicting and solving the problem. Integration of propulsion and flight control systems appears to be the most promising solution if the interaction effects can be adequately predicted early in the vehicle design. Significant performance, stability, and control improvements may be realized from a cooperative control system.

Needed improvements in the maneuvering performance of combat aircraft appear to be possible through the simultaneous application of advances in various disciplines in such a way that they complement one another and magnify the benefits derived. The highly maneuverable aircraft technology (HiMAT) program is being conducted to investigate such multidisciplinary concepts. The program has three phases: preliminary studies, conceptual design studies, and the final design and construction of a test airplane. Work is now in the second phase. The test airplane will be a scaled model flown by a remotely piloted research vehicle technique. This paper outlines the HiMAT program and indicates the types of concepts being considered.

The lack of sufficient formal education in the field of reliability is an accepted fact by both the engineering educator and reliability manager. This paper describes this problem in some detail and contrasts the state of reliability education with other more established disciplines. Some of the previous ambitious attempts to remedy this situation are discussed and some more limited and perhaps more feasible suggestions are presented.

THERE HAS BEEN A LACK OF INFORMATION ON IMAGE BRIGHTNESS IN AUTOMOTIVE REAR VISION SYSTEMS AS RELATED TO THE DRIVER'S NEEDS. THIS PAPER PRESENTS DATA ON DRIVER EVALUATION OF BRIGHTNESS, IN THE FORM OF VISIBILITY AND GLARE RATINGS OF REAR VIEW MIRROR REFLECTANCE LEVELS, BASED UPON ACTUAL DRIVING EXPERIENCES. THE EFFECTS OF ROADWAY TYPES AND VARIOUS AMBIENT LIGHTING CONDITIONS ARE DISCUSSED, AND RANGES OF ACCEPTABLE REFLECTANCE LEVELS ARE RECOMMENDED. THIS STUDY WAS A TASK GROUP EFFORT PERFORMED BY THE SAE REAR VISION SUBCOMMITTEE. /AE/

Direct impact to the larnyx is usually prevented in accidents by ths]protective nature of the chin. In some situations, the occupant motions leave the larnyx unprotected and susceptible to impact by the steering wheel rim or instrument panel. As one of the unpaired vital organs of the body, there is no easy way to provide an alternative for its functions when the larnyx is lost or damaged. Information available on the tolerance of the unembalmed human larnyx to force is quite limited. This paper describes a multidisciplinary study to determine the response of unembalmed human larynges to blunt mechanical loading and to interpret the response with respect to clinical data. Fresh intact larynges were obtained at autopsy and tested at either static or dynamic loading conditions utilizing special test fixtures in materials-testing machines. Load and deformation data were obtained up to levels sufficient to produce significant fractures in both the thyroid and cricoid cartilages. Additional information was obtained in the form of permanent dimensional changes through direct measurements and location of fracture sites by use of xeroradiography. Final evaluation of the damage was performed following dissection of the laryngeal structure. The results of the tests are analyzed and interpreted in relation to establishing tolerance criteria for laryngeal loading.

The present paper discusses the NASA Langley Research Center stall/spin research program to improve the design and the evaluation techniques relative to stall/spin characteristics of general-aviation aircraft. The program encompasses model wind-tunnel tests, spin-tunnel and radio-control model tests, and full-scale airplane spin tests. Initial spin-tunnel results on models with several tail designs representative of light airplanes and several testing techniques are discussed.

The paper discusses the fundamental origins of truck noise and shows the rate at which the noise of each individual source increases with speed. Various means of controlling noise from each component are considered. A method of predicting engine noise, and hence vehicle noise, from basic engine speed and piston diameter data is given and the significance of this information to the engine designer is emphasized.

THIS paper outlines a new method of measuring end-gas temperatures within the cylinder of an operating engine. The new instrument measures the acoustical properties by the pulse method, transmitting an acoustical impulse through a gas path of known length and measuring the time of propagation through the gas. The method yields a value for the average velocity of sound in the path. The authors describe the instrument and engine modifications necessary. The results of tests are also discussed, with a detailed description of one series. The appendixes outline the mathematical steps of finding the sound velocity in gas mixtures and the fuel-air cycle for the detailed series of tests.

Classic reliability theory holds that a component's reliability characteristics include wear-out. Regulations governing overhaul time limits assume, therefore, that scheduled component overhauls are good preventive maintenance when done before wearout has gone too far. This paper disputes current practice and holds that scheduled component overhauls are almost never justified. This position is supported by illustrations from four special maintenance programmes currently in use at United Air Lines.

It has been recognized that low-temperature engine cranking characteristics are not related to extrapolated viscosity for multiviscosity engine oils. At the request of SAE, the Coordinating Research Council (CRC) is endeavoring to develop a meaningful low-temperature viscometric technique to replace the extrapolated system now used in the SAE classification. The first step in accomplishing this objective was to develop a reproducible engine cranking technique. This phase of the program has been completed and a cranking technique known as CRC L-49-663 has been developed. The development of the technique is discussed in this paper.

VARIOUS TYPES OF EXISTING AUDIBLE WARNING SYSTEMS AND THEIR HISTORICAL DEVELOPMENT ARE DISCUSSED IN THIS PAPER, TOGETHER WITH AN ANALYSIS OF THEIR EFFECTIVENESS IN FULFILLING THEIR PRIME FUNCTION - NAMELY, TO WARN PEOPLE OF IMMINENT DANGER. IT IS CONCLUDED THAT SUCH SYSTEMS PERFORM ADEQUATELY IN MANY SITUATIONS, BUT NOT WHEN THE RECIPIENT OF THE WARNING SIGNAL IS INSIDE ANOTHER VEHICLE. IT IS SUGGESTED THAT ALTERNATIVE MEANS BE DEVELOPED FOR WARNING THE OCCUPANTS OF VEHICLES OF IMMEDIATE DANGER SO THAT AUDIBLE WARNING SYSTEMS OF REDUCED ACOUSTIC POWER CAN BE USED TO WARN PEDESTRIANS OR OTHER PERSONS OUTSIDE VEHICLES. /DOT/

The SAMMIE computer-aided workplace and work task design system is intended to facilitate the consideration of human factors within the design process from the conceptual, pre-mock-up stage of design onwards. The software consists of six main parts: a computerized man-model, a workplace modelling system, a language with which to describe the work tasks to be performed in that workplace, heuristic rules for workplace layouts, various measures of effectiveness which can aid the assessment of the suitability of the workplace, and finally a system for interactive man-machine communication. The workspace model and the model of the operator are displayed on a screen of an interactive graphics terminal and the workspace is then evaluated for an operator performing specified tasks. The dimensions and arrangements of the workspace, the dimensions of the operator, and to a lesser extent the work task may all be interactively changed, and the proposed design then reevaluated. Measures of effectiveness include reach, checks on visual suitability, and an evaluation of the methods and times required to perform the task. These, and other measures, may be used by the computer itself, and interactively under the designer's control.