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As the evidence of the contribution of intoxicated drivers to vehicular fatalities continues to mount, interest has grown in the development of novel countermeasures. One approach now being considered involves the use of a device installed in the automobile which automatically determines if the driver is intoxicated and prevents the driver from operating the vehicle when intoxication is determined. In this paper such devices are discussed with particular consideration given to the method of determining intoxication, the point in time when the determination is made and their applications. The paper also discusses the Transportation Systems Center's research program directed to dealing with this problem.

A group of specialists was assembled at the U. S. Army Engineer Waterways Experiment Station (WES) to consider quantitatively the various elements of the entire vehicle mobility problem and to suggest an approach for achieving a substantial degree of solution. One specific purpose of the meeting, and the one that is the subject of this paper, was to design a number of vehicles capable of operating in remote areas of the world where extremely soft soil conditions predominate. This paper describes the application of the design methods and presents the two wheeled-vehicle concepts and the one tracked-vehicle concept that were evolved to satisfy the basic assumptions.

A computer program has been developed to obtain subsonic or shockfree transonic, nonviscous flow analysis on the hub-shroud mid-channel flow surface of a turbomachine. The analysis may be for any annular passage, with or without blades. The blades may be fixed or rotating and may be twisted and leaned. The flow may be axial, radial or mixed. Blade surface velocities over the entire blade are approximated based on the rate of change of angular momentum. This gives a 3-D flow picture based on a 2-D analysis. The paper discusses the method used for the program and shows examples of the type of passages and blade rows which can be analyzed. Also, some numerical examples are given to show how the program can be used for practical assistance in design of blading, annular passages, and annular diffusers.

The paper reviews the experimental, theoretical and applications work by several authors on a glass sealing technique which was announced five years ago. In the process, an electrostatic field is utilized to promote bonding at relatively low temperatures. The process variables and seal properties are described in detail. A discussion is presented of the mechanisms which are believed to play a role in bond formation. As an example of the utility of the technique, its highly successful application to the mounting of strain gauges is described.

Turbojet engine reliability has long been an intense interest to the military users of this type of aircraft propulsion. With the recent inauguration of commercial jet transport this subject has assumed a new dimension of importance. In January l96 the Lewis Research Center of the NASA (then the MACA) published the results of an extensive study on the factors that affect the opera- center dot tional reliability of turbojet engines (ref. 1). At that time the report was classified Confidential. In July l98 this report was declassified. It is thus appropriate at this time to present some of the highlights of the studies described in the NASA report. In no way is it intended to outline the complete contents of the report; rather it is hoped to direct attention to it among those who are center dot directly concerned with this problem. Since the publication of our study over three years ago, the NASA has completed a number of additional investigations that bear significantly on this center dot subject. A second object of this paper, therefore, is to summarize the results of these recent studies and to interpret their significance in relation to turbojet operational reliability.

Copy of paper for Automotive Engineering Congress held in Detroit, MI, January 14-18. Enumerates principles of VA, including "a study of decision conditions," that affect cost. Also transcript of speech for same conference with same title, but different

Several unique techniques and related devices are described which are in use at the Lewis Research Center for off-design testing of fan and compressor sections in full-scale jet engines. The devices presented permit a wide range of experimental conditions and minimize downtime for hardware changes. The techniques involve use of such devices as inlet pressure distortion jets, a hydrogen burner for inlet temperature distortions, fan back pressure jets to simulate a variable area nozzle, and either an inflow-outflow bleed system or a fuel spurt system to alter compressor discharge pressure.

The Lewis Research Center cold-flow model externally blown flap (EBF) noise research test program is summarized. Both engine under-the-wing and over-the-wing EBF wing section configurations were studied. Ten large scale and nineteen small scale EBF models were tested. A limited number of forward airspeed effect and flap noise suppression tests were also run. The key results and conclusions drawn from the flap noise tests are summarized and discussed.

The objectives, program plan, schedule, pollution and performance goals, program approaches to pollution reduction, and status of the project are presented. Advanced supersonic transport and combustion noise programs are also discussed. The phases of the program consist of the following: (1) screening of low pollutant combustors, (2) refinement of the best combustors, and (3) engine demonstration of the best combustors. It is stated that all combustor designs investigated appear capable of achieving the idle pollutant goals with additional development effort.

A summary is presented of an acoustic test program for investigating engine noise suppression and jet/flap interaction noise associated with an EBF STOL powered lift system. A highly suppressed TF-34 engine and EBF wing were used in the investigation. The engine was suppressed 21 PndB to a level of 94 PndB. An UTW powered lift system was tested with conventional, mixer, and decayer-type nozzles. The configuration with velocity decayer nozzle and acoustically treated shroud had the lowest noise (98 PndB). An OTW configuration with non-decayer nozzle was about 10 db quieter than the corresponding UTW system. UTW and OTW noise data are compared with scale model correlations.

Several candidate alloys and coatings were evaluated for use in automobile thermal reactors. Full-size reactors of the candidate materials were evaluated in cyclic engine dynamometer tests with a peak temperature of 1040 C (1900 F). Two developmental ferritic-iron alloys, GE-1541 and NASA-18T, exhibited the best overall performance by lasting at least 60 percent of the life of test engine. Four of the alloys evaluated warrant consideration for reactor use. They are GE-1541, Armco 18 SR, NASA-18T, and Inconel 601. None of the commercial coating substrate combinations evaluated warrant consideration for reactor use.

The technical feasibility is described of substantially reducing the noise levels of existing JT8D powered aircraft by retrofitting the existing fleet with quieter refan engines and new acoustically treated nacelles. No major technical problems exist that preclude the development and installation of refanned engines on aircraft currently powered by the JT8D engine. The refan concept is technically feasible and provides calculated noise reductions of from 7 to 8 EPNdb for the B727-200 aircraft and from 10 to 12 EPNdb for the DC-9-32 aircraft at the FAR Part 36 measuring stations. These noise levels are lower than both the FAR Part 36 noise standards and the noise levels of the wide-body DC-10-10. Corresponding reductions in the 90 EPNdb footprint area are estimated to vary from about 70 percent for the DC-9 to about 80 percent for the B727.

Ride quality vibration criteria applicable to the design and evaluation of air and surface transportation systems are described. Consideration is given to the magnitude of vehicle vibration experienced by the passenger, the frequency of vibration, the direction of vibration measurements are presented for a variety of air and surface transportation systems. In addition, simulator data on seat dynamics and passenger response are presented. Results suggest the relative merits of various physical descriptors and measurement locations for characterizing the vibration in terms suitable for the design and/or evaluation of transportation systems.

In order to determine spray droplet size in diesel engine, fuel was injected into high pressure gaseous environments with a diesel engine injection system. Droplet size was measured using the liquid immersion sampling technique with the mixtute of water-methylcellulose solution and ethanol used as an immersion liquid for diesel fuel oil. The volume distribution of diesel spray droplet is well correlated with chi-square distribution with freedom, φ=8 in the range of this investigation. The Sauter mean diameter increased with increasing back pressure, with the amount of fuel in a spray and with decreasing pump speed. An empirical correlation was developed between effective injection pressure, air density, the quantity of the fuel delivery and the Sauter mean diameter of spray droplets.

Low speed sectional characteristics of a high lift airfoil are studied and a comparison is made of those characteristics with the predictions of the theoretical methods used in the airfoil's design. The 13.1 percent-thick, UI-1720 airfoil was found to achieve the predicted maximum lift coefficient of nearly 2.0. No upper-surface, flow separation was found below the stall angle of attack of 16 degrees; it appeared that stall was due to an abrupt leading edge flow separation.

An analytical and experimental investigation of possible contributing factors in jet aircraft turbulence upsets was conducted. Major contributing factors identified included autopilot and display deficiencies, the large aircraft inertia and associated long response time, and excessive pilot workload. An integrated flight and thrust energy management director system was synthesized. The system was incorporated in a moving-base simulation and evaluated using highly experienced airline pilots. The evaluation included comparison of pilot workload and flight performance during severe turbulence penetration utilizing four control/display concepts: manual control with conventional full panel display, conventional autopilot (A/P-A) with conventional full panel display, improved autopilot (A/P-B) with conventional full panel display plus thrust director display, and longitudinal flight director with conventional full panel display plus thrust director display. Simulation results show improved performance, reduced pilot workload, and a pilot preference for the autopilot system controlling to the flight director command and manual control of thrust following the trim thrust director.

Jet engine testing is reported concerned with the effect of inlet pressure and temperature distortions on engine performance and involves the use of numerous miniature pressure transducers. Despite recent improvements in the manufacture of miniature pressure transducers, they still exhibit sensitivity change and zero-shift with temperature and time. To obtain meaningful data, a calibration system is needed to determine these changes. A system has been developed which provides for computer selection of appropriate reference pressures selected from nine different sources to provide a two- or three-point calibration. Calibrations are made on command, before and sometimes after each data point. A unique no leak matrix valve design is used in the reference pressure system. Zero-shift corrections are measured and the values are automatically inserted into the data reduction program.

Large multipurpose launch vehicle concept noting two stage propulsion system, payload flexibility and mission performance

Design, compatibility, and system integration of reaction control system configuration of x-15a aircraft

Feasibility of phosphoric acid water vapor electrolysis cell for spacecraft cabin air conditioning system

Burner rig tests on simulated turbine blades, with and without internal cooling, to predict thermal fatigue performance

Spacecraft designed to provide flight test measurement of ion thrustor electrical parameters and thrust

The current mobility available to tactical units is discussed and the problems surrounding the specific requirements and the determination of vehicle performance are presented. Mobility is broken down into seven elements and the method for specifying each element is presented. A complete discussion of the soft soil performance is reviewed and future mobility requirements are offered in general terms.

An exploratory evaluation of ceramics for automobile thermal reactors was conducted. Potential ceramic materials were evaluated in several reactor designs using both engine dynamometer and vehicle road tests. Silicon carbide contained in a corrugated metal support structure exhibited the best performance lasting over 800 hours in engine dynamometer tests and over 15,000 miles (24,200 km) of vehicle road tests. Reactors containing glass-ceramic components did not perform as well as silicon carbide. But the glass-ceramics still offer good potential for reactor use. The results of this study are considered to be a reasonable demonstration of the potential use of ceramics in thermal reactors.

Apollo spacecraft pyrotechnic systems and devices functions during lunar exploration mission and in aborts

Ultimate bending moment capability of thin walled pressure stabilized cylinder with typical axial loads demonstrated to be 50 percent greater than bending moment at which compressive wrinkling occurs

Construction and testing of water electrolysis subsystem to generate breathable oxygen for use in spacecraft or aircraft environment

A turbine blade temperature measuring system for liquid oxygen turbopumps is reported. The system includes a three mode, two-input optical signal processor, interconnecting cable, and four sensor heads. Two of the heads are aperture type, while the other two are lens type. This system is applicable to a temperature range of 1400 to 2200 F.

Directional solidification of nickel base alloy TAZ-8B to enhance potential for advanced gas turbine engine applications

A general analysis is made of the turbulent refractivity spectrum in and beyond the limiting microscale and a relation derived for its scattering reflectivity in either the back or bistatic directions. Radar reflectivity is computed as a function of wavelength for regions of CAT. The results are compared to the minimum detectable reflectivity of airborne radars having optimum state of the art characteristics at each wavelength. It is shown that the best radars now feasible can barely detect the most reflective CAT at 10 n mi (i.e., 1 minute warning). A 20-db improvement in sensitivity is required for detection of most CAT, which appears to be just attainable by pre-detection integration. The optimum wavelength to implement is 5–6 cm. The best radar at this wavelength will also detect circus clouds reliably. Whether detecting clouds or chaff a measure of the echo fluctuation (or Doppler) spectrum is required to identify the intensity of CAT. However, in the case of high altitude clear air echoes, ...

New aerospace-related technology in nonaerospace applications, noting NASA and petroleum industry

Space propulsion systems requirements, considering environmental influence, propellant combinations and mission criteria

Runway condition and tire tread design in relation to pneumatic tire braking and directional control on wet pavement