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Trip time requirements between points on earth can be reduced by use of hypersonic aircraft if the range is sufficiently large so as to minimize the effect on average speed of the time of acceleration and deceleration. See Fig. 1. The objective of this study is to determine if it is technically feasible to use airbreathing propulsion systems to provide an intercontinental vehicle which will bring virtually all major cities of the world within two hours flying time of each other. An extensive study of various propulsion and performance aspects of a single-stage long range Mach 7 delta wing trans port, Fig. 2, 30,000 lb payload (125 passengers and cargo), has been completed. The study encompasses consideration of the propulsive performance of a hypersonic ramjet design featuring lift augmentation. Particular attention is given to the influence of geometry, equivalence ratio, diffuser recovery characteristics, and boundary layer bleed on this performance.

In this paper a new method for die milling, which significantly reduces the volume of the scallops while maintaining the same overall productivity as the conventional operation, is proposed. The method is based on the superposition of an additional motion, termed the tertiary motion, onto the conventional motion, i.e., spindle rotation and feed, of the milling process. This additional motion results in the capability to control the topography of the generated surface and, for suitable combinations of the motion parameters, in a very effective means for scallop removal. The basic theoretical concepts of the approach are summarized addressing the relationship between tool geometry and the kinematics of the operation and the resulting surface topography. Subsequently a method is introduced for the synthesis of three-dimensional surfaces through computer simulations.

An alumina-based LNT is being developed through laboratory studies, for diesel vehicle applications. This LNT provides high NOx conversion efficiency at low temperature (150 to 350°C, especially below 200°C), which is very important for the exhaust-gas after-treatment of diesel passenger vehicles. Addition of 2 to 4 wt% of alkaline-earth metal oxide or other metal oxides to the alumina LNT formulation improves NOx reduction activity at the high end of its active temperature window. More significantly, the alumina-based LNT can undergo the de-SOx process (the process of removing sulfur from the catalytic surfaces) very efficiently: within 1 minute at the relatively low temperature of 500 to 650°C under slightly rich conditions (λ = 0.98 to 0.987). Such a mild de-SOx process imposes minimal thermal exposure, causing almost no thermal damage to the LNT, and helps minimize the associated fuel penalty.

Highways today have become instruments for economic progress -- a principal means of relieving traffic congestion and enhancing safety in urban and suburban areas. Expensive and time-consuming distances separate people from available employment at city edges and surrounding suburbs. One concept, mass rail and rubber-tired transit, with fringe and/or central business district parking for reasonable fees, would facilitate the movement of masses. Another program, Traffic Operations to improve capacity and safety, involves expanding the federal aid primary system to involve future improvements, such as channelized intersections, left turn slots, preferential bus lanes, and signal control systems. The implementation of such programs is discussed.

Over the past 30 years significant progress has been made in reducing air pollution from heavy-duty diesel engines. In the coming decades additional reductions will occur. These important emission reductions have occurred because of a series of increasingly stringent emission standards. These requirements began in 1970 with standards for opacity smoke emissions from highway heavy-duty engines. During the 1980's and 1990's, additional pollutants, primarily particulate matter and oxides of nitrogen, were controlled through changes in emission standards and test procedures (hydrocarbon and carbon monoxide standards were also included, but were targeted primarily at gasoline fueled rather than diesel fueled heavy-duty engines). In the mid-1990's, emission standards for nonroad diesel engines were implemented for the first time.

The paper presents a concise view of federal regulatory activities in the area of aircraft noise. The elements and participants in the noise problem are identified, and the historical background leading to the enactment of federal legislation supporting FAA regulatory activities is presented. The scope and status of FAA regulations, as well as the constraints and alternatives affecting an ultimate resolution of the problem, are reviewed. A prospectus is offered.

The subject of alternate fuels has been addressed for the past 20 years in an effort to solve emissions and world fuel supply concerns. A recent study of the available literature and technology to date pointed out a need for a single source of information for the fleet operator. This paper will be divided into discussions of emissions requirements, world fuel supplies, alternate fuel options and the technical concerns to the fleet operator.

The influence of women on equipment design is well reflected in current Army efforts to accommodate the female soldier in her ever expanding role. Women have been admitted into all military occupational specialties, formerly considered “non-traditional”, with the exception of combat related areas. The growing presence of women in the Army and their projected utilization have not been sufficiently addressed. Recent Army requirements, however, emphasize that the enlisted female must now be equally considered in every respect in all Army materiel design including combat equipment. This paper discusses the need for up-to-date information concerning the capabilities and limitations of the female to determine the compatibility of existing materiel and that currently under development or anticipated. A number of design considerations relative to the findings of recent studies and surveys are included.

Emission control requirements and the desire for improved fuel economy have led to many studies concerned with improving combustion chamber design, fuel metering, and ignition. This paper describes an experimental programmable ignition system based on a new principle of operation. The ignition system provides for electronically controlled changes in spark duration, spark current level, and restriking rate. The ignition system also combines a very fast risetime with a controlled duration. Extensive multicylinder engine dynamometer test data are presented which indicate that improved ignition can be of benefit at marginal engine operating points.

The Ferrum piston is a diesel engine piston developed at Elko over the last 20 years. Its main features are a cross head design with a cast iron crown. The paper explains the detail of the design and why some engines need the new pistons and how most diesel engines can profit from these pistons. Particular attention is being given to durability and endurance, to engine performance as far as s.f.c., torque, smoke, noise, emissions, heat rejection etc. is concerned and to economic aspects such as production feasibility and costs.

The Fiat 124 AC engine for the sports car derives from the 124 A engine for the sedan. The two engines have many parts in common so that, although different in configuration, both can be machined on the same production line. The main feature of the sports engine is the use of a cylinder head with twin OH camshafts and directly controlled, inclined valves, suitable for high rpm operation and high specific power without affecting the inherent flexibility of the engine in town traffic. For export to the United States, emissions are controlled to the levels required by the current Federal Regulations.

The Fiat-SRM hydraulic transmission in a version suitable for city buses is described with regard to its basic features and to the different operational modes. The transmission uses a two-stage torque converter with fixed and rotating reactor, which provides two phases of hydraulic drive in the medium- and low-speed range. In the latter, the reaction torque on the reactor is added to the output torque by planetary gears, obtaining exceptionally high ratios at the stall point. A third phase in direct mechanical drive is used in the high-speed range, using a clutch bypassing the converter. The different modes of operation are automatically controlled by an electronic unit, which is described with particular regard to its characteristics and to the possibility of obtaining high continuous decelerations on steep gradients, using the hydraulic braking offered by the transmission.

Fibrous materials had been used as sound absorption materials for over one century. The current sound absorption theory is still the Rayleigh model. But it not agrees with the practice even though it had been studied for over 100 years. Based of Rayleigh model, Zwikker and Kosten established the theory of acoustical effective density and the effective bulk modulus which is also the popular theory in acoustics literature to explain the sound absorption characteristics of fibrous materials. However, because of the complexity of these expressions, it is difficult to obtain physical insight into the acoustic behavior of the porous materials and to determine the dominant mechanism for sound absorption for a given material at a given frequency. Alternatively there are very simple expressions. A new theory was put forward that fibrous material absorb the sound by the fiber's vibration.

Field tests have been run in a variety of vehicles to assess the wear and cleanliness performance of API SG (SG) compared to API SF (SF) and lower quality oils. The field tests were run in simulated delivery service with light trucks and in taxis. Oil drains and filter changes were maintained at 24,000 km to provide severe service conditions. Comparing overhead cam wear in the Sequence V-D, Sequence VE and the field demonstrated that SG quality oils have a significant margin of safety for field wear control. SG quality oils provided excellent engine cleanliness protection in the field that was significantly better than the cleanliness afforded by SF quality oils. Both SF and SG quality oils performed well in bearing wear protection. Used oil analyses were helpful for assessing the overall field performance of engine oils.

A small overlap frontal crash test has been recently introduced by the Insurance Institute for Highway Safety in its frontal rating scheme. Another small overlap frontal crash test is under development by the National Highway Traffic Safety Administration (NHTSA). Whereas the IIHS test is conducted against a fixed rigid barrier, the NHTSA test is conducted with a moving deformable barrier that overlaps 35% of the vehicle being tested and the angle between the longitudinal axis of the barrier and the longitudinal axis of the test vehicle is 15 degrees. The field relevance of the IIHS test has been the subject of a paper by Prasad et al. (2014). The current study is aimed at examining the field relevance of the NHTSA test.

ONE method employed in a fundamental investigation of the composition of lubricating oils as it affects the viscosity characteristics has involved the synthesis of viscous oils by polymerizing a wide range of olefins with a condensing agent, such as aluminum chloride. Many thousand gallons of synthetic lubricating oils have been made within the last two or three years from olefins produced by cracking paraffin waxes. Details of the process have been published previously and hence are not included. The present paper deals with the characteristics of two such oils that have been synthesized in commercial quantities. The raw materials and the process of manufacture make these more expensive than ordinary motor oils, but their temperature-viscosity characteristics make them desirable for use in transmission and steering mechanisms and in hydraulic shock-absorbers, as they are less susceptible than the usual oil to viscosity changes with changes of temperature.

THE FIESTA, announced in July 1976, extends the European Ford model range by adding a new vehicle in the sub-compact class. The development of the FIESTA, to suit the market in North America and to comply with the motor vehicle safety standards of the United States and Canada, was completed in early 1977. The car was presented to the US public in May of that year. In part one of this paper the European version is described with special reference to those innovations which are of most interest in Europe. Part two deals with the North American version of the FIESTA with its specific requirements for comfort and conformity to safety regulations.