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Viewing 161941 to 161970 of 188295
1974-02-01
Technical Paper
740642
Robert G. Jackson
The use of coal as a prime energy source is examined. The author focuses on the process of coal gasification to produce a synthesis gas for subsequent conversion to either gaseous or liquid products, and particularly on the methanol process. The production of methanol is described, as are ways of using it commercially.
1974-02-01
Technical Paper
740627
Charles T. Hare, Karl J. Springer, William Rogers Oliver, William H. Houtman, Thomas A. Huls
Seven motorcycles, ranging in size from 100 to 1200 cm3, were tested for emissions characterization purposes. They were operated on the federal seven-mode test procedure (for 1971 and older light-duty vehicles), the federal LA-4 test procedure (for 1972 and later LDVs), and under a variety of steady-state conditions. Four of the machines tested had 4-stroke engines, and the other three had 2-stroke engines. Emissions which were measured included hydrocarbons, CO, CO2, NO, NOx, O2, aldehydes, light hydrocarbons, particulates, and smoke. Emissions of SOx were estimated on the basis of fuel consumed, and evaporative hydrocarbon losses were also estimated. Crankcase “blowby” emissions from one 4-stroke machine were measured. The impact of motorcycles on national pollutant totals was estimated, based on the test results and information from a variety of sources on national population and usage of motorcycles.
1974-02-01
Technical Paper
740616
Rex W. Oyler
This paper covers automotive lighting devices and allied equipment as they might be used in front, side, and rear lighting. Consideration is given to legal aspects, standardization opportunities, hardware involved, and criteria for final decision making. Comparisons of relative headlight seeing distances have been made, and suggestions for an intermediate or mid-beam configuration are proposed. The three-beam approach appears to offer the greatest immediate potential for head-lighting improvement.
1974-02-01
Technical Paper
740618
J. F. Hittle, A. R. Schuette
Because of the increasing complexity of commercial trucking operation and management, the truck automatic transmission is being found to be an asset in terms of overall vehicle economics-in addition to its long recognized features of ease of operation and safety. A number of salient vehicle cost factors upon which the truck automatic transmission has an impact are discussed-along with the transmission design principles which lead to that impact. Acceptance of this premise by the trucking industry is shown by market segment. In addition to discussing the contribution of the truck automatic transmission toward improving the overall economics position of today's commercial vehicles, this paper gives indication of forthcoming refinements in transmission design which will further reduce fuel consumption costs.
1974-02-01
Technical Paper
740692
L. C. Broering, L. W. Holtman
Tests were conducted with several production diesel engines and one prototype low-emission diesel engine to determine the effect of fuel properties on exhaust emissions and engine performance. Fuel cetane number was found to be the most significant fuel property; low cetane fuels resulted in higher hydrocarbons and oxides of nitrogen and increased noise. Conversely, higher cetane fuels produced lower emissions and noise, and also improved engine starting characteristics. The degree of these effects was influenced by engine configuration. Although engine design changes can result in substantial emissions reduction, fuel properties can also influence achieveable levels.
1974-02-01
Technical Paper
740673
Ronald Sisson
This paper describes the concept, design, and options of a new power shift transmission family for industrial equipment in the 50-100 hp range. The converter, clutch, and gearing arrangements provide the basis for various transmission configurations with both a drop and straight through output. The designs allow multiple usage of components within a transmission and between different sizes of transmissions. The various gearing, bearing, and clutch designs are based on proved experience factors, and as such will provide a new reliable family of transmissions.
1974-02-01
Technical Paper
740674
John M. Beeson, Jim R. Wiebe
Funk Manufacturing has designed and developed a 60-100 hp power shift transmission to meet the needs of industry. Construction details of the 4000 power shift are reviewed. This design produces the most compact arrangement with the fewest parts for minimum cost. Unique clutch arrangements and control valve designs are described in this paper. A comparison of the 2- and 3-speed versions is detailed, as well as the interchangeability of parts for both speeds. Optional features of the transmission are also noted.
1974-02-01
Technical Paper
740606
William H. Close
Based on the past research of the U.S. Department of Transportation, this paper is an attempt to make the case for tire noise regulation and to illustrate the implications of such regulations to tire users. The paper examines the effects of speed, load, tire tread type, road surface, and placement of tires on combination truck vehicles insofar as passby sound levels are concerned. A concluding table of expected roadside sound levels based upon typical tire use indicates the potential restrictions in tire types that are inherent in presently proposed federal noise regulations on interstate motor carriers. It is concluded that as significant technological improvements are implemented in the design and regulation of truck engine noise, more severe tire user requirements will follow in order that tire noise keep pace with declining engine noise.
1974-02-01
Technical Paper
740604
Franklin B. Airheart
Various approaches to truck disc brake design are discussed. Design of the disc and the effect of its design on brake performance show current designs being proposed may be inadequate. Lining area must be adequate for long life without restricting cooling. Piston retraction and adjustment by mechanical means is more reliable than seal retraction. A multiple disc oil-cooled hydraulic disc brake can provide extended life and high torque in a small diameter package. Air-actuated disc brakes eliminate the need for hydraulics, but introduce problems in force multiplication and brake-to-brake balance.
1974-02-01
Technical Paper
740603
S. L. Stokes
This paper outlines various laboratory tests which can be utilized to evaluate heavy truck disc brakes. The methods described include supplemental techniques derived from improved dynamometer procedures which assure that the brake components and assembly will perform the intended function and that a practical and effective design has been obtained. They ensure that the brakes will provide the “toughness” required in the “real world” environment.
1974-02-01
Technical Paper
740614
John Voevodsky
A deceleration warning light system installed on taxicabs in San Francisco for 12.3 million miles of normal on-road driving reduced the rear-end collision rate by 60.6% compared to the rate for a concurrent control group of cabs which traveled 7.2 million miles. Comparing the experimental group with the concurrent control group revealed that the warning light prevented 5.4 collisions per million miles, 1.02 cab driver injuries per million miles, and $643 of taxicab damage per million miles. An amber light was center mounted on the rear of several hundred taxicabs and was designed to communicate information about the taxi's deceleration to following drivers.
1974-02-01
Technical Paper
740608
R. F. Miller, D. B. Thrasher
This paper discusses the importance of the spectral distribution of the energy in the sound to the dB(A) level of the usual passby test. A described technique obtains reproducible “real-time” spectra from the nonstationary sound field. Doppler effect and source frequency shift are quantified in relating these spectra to the tread pattern repetitions. Inverse square law fitting is viewed through the two-source-microphone relation which changes during the spectral window period. Spectra are shown for 6, 12, and 50 ft (1.83, 3.66, and 15.2 m) passby microphones and for a microphone carried on the truck.
1974-02-01
Technical Paper
740593
Arthur C. Haman
Paper describes three collegiate automobile runs sponsored by American Motors Corp. to demonstrate that savings in fuel are possible when good driving practices are observed. Driving 1974 Gremlins, the young winners proved that “typical” drivers can in fact achieve economies in fuel of the kind that are being sought nationally at the present time. Reduction of speed proved to be a major contributing factor.
1974-02-01
Technical Paper
740590
J. A. Tennant, R. H. Jensen, R. A. Potter
The development, manufacture and testing of a new anthropomorphic test dummy (GM-ATD 502) is discussed. Improvements in performance repeatability and reproducibility of the dummy are documented and the anthropometric and biomechanical basis of the design described. The development of repeatable testing procedures and of dummy features that enhance the accuracy of the initial test setup are also discussed.
1974-02-01
Technical Paper
740589
R. L. Stalnaker, D. Mohan
Serious injuries are caused to the chest and thoracic organs both in front and side automobile collisions, and statistical surveys indicate that overall chest injuries are the third most frequent after head and the lower limbs. For safer design of restraint systems and vehicle interiors experimental data has to be obtained to establish chest injury criteria. Unembalmed human cadavers were used to conduct nine frontal and fourteen lateral impacts including four with a simulated arm rest. All impacts used a six inch (15.2 cm) diameter impactor with impact velocities ranging from 12 mph (19.3 kph) to 20 mph (32.2 kph). Chest impacts were also conducted on rhesus monkeys and baboons to establish primate-human injury scaling criteria. Four human volunteers were used to obtain static load deflection curves in the lateral and frontal directions. The results of the above experiments and those conducted by other investigators are presented and analyzed.
1974-02-01
Technical Paper
740588
Raymond F. Neathery, Harold J. Mertz, Robert P. Hubbard, Mark R. Henderson
Two Highway Safety Research Institute (HSRI) dummies were tested and evaluated. Based on the analysis given, the HSI dummy should not be used for vehicle qualification testing. However, many of its components offer viable alternatives for future dummy development. The dummy was found to have inadequate biomechanical fidelity in the head, neck, and chest, although its characteristics were very promising and, as a whole, biomechanically superior to the Hybrid II. Its repeatability and reproducibility in dynamic component tests were better than the Hybrid II dummy. In particular, the HSRI friction joints were outstanding in repeatability and had a significant advantage in usability in that they do not require resetting between tests. In three-point harness and ACRS systems tests, the values of injury criteria produced by the HSRI dummy were generally lower than those obtained with the Hybrid II, especially the femur loads in the ACRS tests.
1974-02-01
Technical Paper
740602
W. T. Birge, K. H. Rinker
Disc brakes for trucks have been the subject of intensive investigation in the United States since their adoption on passenger cars and light trucks in the mid 1960s. Although the basic industry work has covered the full range of medium and heavy hydraulic and air-braked trucks, the first commercial use of heavy-duty calipers will be on the front axles of heavy air-braked trucks where their stability and high torque characteristics are of particular advantage in meeting FMVSS 121, scheduled as of this writing to become effective March 1, 1975.
1974-02-01
Technical Paper
740598
Jim Hanks, Charles Selby, Philip Loken
This paper discusses bearing arrangements designed to maximize stability and load capacity within available envelope dimensions. Also presented is a means of negating the detrimental effects of cylinder reactions in a pneumatic clutch, while at the same time increasing the torque-to-space ratio. These concepts were realized during a study expressly intended to view the various design elements with the requirements of a diesel truck fan clutch in mind. Further, the study resulted in the development of a nonmodulating, direct acting thermal control valve, specifically engineered to complement the action of a pneumatic fan clutch as part of an overall temperature controlling system.
1974-02-01
Technical Paper
740594
Robert C. Stempel, Stuart W. Martens
In 1968, a major oil company cancelled its annual automobile economy run after sponsoring it for 18 consecutive years -presumably due to lack of interest from the public and the press. Almost coincident with that cancellation was the beginning of production automobile exhaust emission control on a national basis and a downward inflection in the historic trend of automobile fuel economy. In contrast, the past year has seen a major revival of interest, by both the public and the press, in fuel economy. In the next few weeks, the nation will be introduced to a new direction in automotive exhaust emission control which will profoundly affect the fuel economy trend. Perhaps equally, or even more important, the next few months are expected to see major national decisions on future automobile emission control which will likely have a significant influence on the direction taken by automobile fuel economy a few years hence.
1974-02-01
Technical Paper
740489
James F. Woodall
The FAA retrofit feasibility program is a success story. The cooperation of the aircraft industry in general, and the FAA's contractors in particular have made the success of the program possible. We can now state that all JT3D- and JT8D-powered aircraft can meet reduced noise levels, such as FAR 36 levels, by means of technologically feasible and economically reasonable nacelle retrofit solutions. These solutions will not aggravate the energy crisis by virtue of a negligible increase in fuel consumption for the nominal flight conditions. A Notice of Proposed Rulemaking (NPRM) is about to be disseminated which could lead to the requirement that all JT3D/JT8D-powered aircraft be retrofitted by 1978 with quiet nacelles so that FAR 36 requirements can be satisfied.
1974-02-01
Technical Paper
740488
Rollo G. Smethers
The short-haul transportation problem, worldwide, is characterized by congestion both on the ground and in the air. Solutions in the form of ground transportation are expensive in terms of land utilization, high development costs, their adverse effect on the environment and ecology, and are 20-30 years in the future. STOL offers a solution, but the high cost of land for downtown STOLports has precluded implementation. The STOL amphibian provides a solution which uses existing waterways situated downtown in every major city. It will relieve ground congestion and alleviate saturated airports. Studies show that such a system meets the ten basic requirements established by the National Environmental Policy Act of 1969 and that it contributes significantly to a reduction in the energy consumed in travel to and from the airports. In terms of facilities, land requirements for the terminal are just 16% of a conventional STOLport.
1974-02-01
Technical Paper
740486
Joseph A. Foster
The development of the first successful scheduled system of STOL operations at a major United States commercial airport has been undertaken at Houston Intercontinental Airport. The STOL system was established to demonstrate the capability of STOL aircraft to operate safely and efficiently in airspace over a major commercial airport simultaneously with high-density scheduled airline operations. The demonstration project included the development of new and experimental runway lighting and loading systems by the Federal Aviation Administration. It encouraged the implementation of new air traffic control procedures that have proved acceptable to the Federal Aviation Administration and to the airline pilots association. This paper describes the development of the system and gives pertinent details of its operation.
1974-02-01
Technical Paper
740485
Richard W. Niedzwiecki, Robert E. Jones
The “Experimental Clean Combustor Program” is a contract effort with primary objectives including the generation and demonstration of technology for development of advanced commercial CTOL aircraft engines with lower exhaust emissions than current aircraft, and the demonstration of this technology in full scale engines in 1976. The program is being conducted in three phases. These consist of screening of low pollutant combustors, refinement of the best combustors and engine demonstration of the best combustors. The combustor screening phase was initiated in December 1972 and is currently in progress. Contracts were awarded to Pratt & Whitney Aircraft and the General Electric Company to evolve combustors for the JT-9D and the CF6-50 engines respectively. Pollution goals are emission index values of 20 and 4 for carbon monoxide and unburned hydrocarbons respectively at engine idle conditions, and an oxides of nitrogen emission index level of 10 at engine takeoff conditions.
1974-02-01
Technical Paper
740484
A. W. Nelson
A new combustor configuration having substantially lower smoke emission characteristics is now in the final stages of development for the JT3D commercial aircraft turbofan engine. In addition, the low-power emissions of hydrocarbons and carbon monoxide are considerably reduced. This burner configuration utilizes many of the features developed in the JT8D turbofan engine smoke reduction program; however, it was also necessary to incorporate air-assist fuel injection nozzles to achieve smoke levels below the EPA regulation requirement of 25. Correction of a nozzle carbon formation problem and further durability testing must be accomplished before this combustor can be released for in-service commercial airline controlled-service use evaluation.
1974-02-01
Technical Paper
740483
A. B. Wassell
Progress in the application of well-known pollution-control techniques to existing engines is demonstrated in relation to the visibility of the exhaust smoke plume in the RB211 and Olympus 593 engines. The reasons for the apparently protracted nature of this progress are discussed and shown to be related to the maintenance of safety and durability standards. Methods being used to reduce the other combustion-generated pollutants are mentioned, especially in relation to the standards promulgated by the Environmental Protection Agency (EPA). A review of some problems associated with measurement and sampling of pollutants is given.
1974-02-01
Technical Paper
740482
E. Rachovitsky
Flight/propulsion control coupling (FPCC) is a flight control technique which couples propulsive forces with aerodynamic forces to affect the flight path and/or flight stability. FPCC is a powerful technique for enhancing and/or enabling performance of advanced airborne vehicles. An overview of the problem of developing the FPCC technology is presented to illuminate some of its key overall requirements. A need for a total system/total mission approach is indicated.
1974-02-01
Technical Paper
740481
G. J. Sevich, E. C. Beattie
New techniques are being developed to determine the analytical design and hardware implementation of multivariable control systems for complex aircraft propulsion systems. The analytical design can be accomplished with applied optimal control theory. Hardware configuration trade studies can be used to determine the best way to implement the propulsion system for a particular aircraft. These techniques may be expanded to the design of integrated flight/propulsion control systems.
1974-02-01
Technical Paper
740500
B.C. Hainline, N.S. Attri
The effect of runway traction on commercial airplane stopping systems is discussed from the airframe manufacturer's point of view. Traction variations with runway contaminants, ice, snow, and rain must be considered along with factors such as airplane and stopping system configuration, weather conditions, performance information, and pilot technique. Further improvements in airplane braking and directional control can be attained if certification and operational regulations provide performance credit, safety, and economic motivation for airline cost of ownership. Recent Boeing brake control system work is summarized as an indication of industry effort to improve performance. Technology requirements and recommendations for improving adverse runway performance are included.
1974-02-01
Technical Paper
740499
F. E. Illston
The purpose of this paper is to focus attention on runway traction problems associated with the operation of high-performance aircraft from an airline pilot's point of view. Because heavy jet aircraft are exposed to a greater risk of skidding on wet slippery runways, runway requirements have become more sophisticated and demanding. The problems of tire hydroplaning and runway slipperiness are particularly hazardous to turbojet operation. Wheel/pavement contact is most significant to stopping and directional control of aircraft movement.
1974-02-01
Technical Paper
740497
Leslie R. Merritt
The Federal Aviation Administration (FAA) has been working to determine the need for changes in the landing certification rule for transport category aircraft. Statistics show that numerous incidents occur each year on wet, snow- or ice-covered runways. A change in certification and operational rules could reduce, or possibly eliminate, such incidents. Numerous investigations have been made with jet transport aircraft and ground vehicle friction-measuring devices to establish relationships on wet surfaces. Results of these investigations have had an impact on possible rule changes and have identified three basic problems. The framework is advanced for a system that can accommodate a change to transport category aircraft-landing certification and operations rules. It is emphasized that any changes must adhere to the standard regulatory process.

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