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The Cargo/Logistics Airlift System Study (CLASS) is an outgrowth of the widespread interest in an advanced air cargo system. In this program NASA seeks to determine more specifically the nature of user requirements for expanded air freight capability. The purpose of the study is to examine the nature and degree of air cargo demand in the 1990 period, assuming that an advanced air freight system were available to the shipping community. NASA wishes to determine whether the requirement for such an airplane is sufficient to justify continued or accelerated research and development activities. In-depth “case studies” were conducted of a number of companies who are representative of potential users. As a part of this study, Lockheed developed a domestic and international air freight forecast, using case study results, for an advanced dedicated air cargo system. A representative domestic and international route structure has been developed from the forecast.

Airport land and operational constraints will force future air cargo terminals to assume a new look if they are to accommodate continued air cargo growth. Improved terminal utilization coupled with cooperative airline endeavors in the use of modular container terminals offers a viable solution which can reduce container handling costs by 40 percent and better through economies of scale. Using a building-block approach with innovative and state-of-the-art equipment, a universally applicable container terminal module is derived which can accommodate growth in customer service level as required, and in multiples can accommodate increasing air cargo flow levels. Example module requirements to the year 2005 are derived for representative U.S. cities.

The development of the WABCO 353FT Twin Engine Elevating Scraper for surface mining applications is an example of advancements being made in mining equipment technology. The 353FT optimizes the benefits of the various scraper configurations available by combining the ability to work under adverse conditions, due to its all wheel drive, with large capacity and the self loading feature of an elevating scraper.

Surface type gear pitting failures were produced on a geared roller test machine and the pitting life data was statistically analyzed by a method that accounts for or minimizes the influence of variables that determine the fatigue environment. The sensitivity of pitting fatigue failures to microstructure is demonstrated. Rollers were carburized at three elevated temperatures, including vacuum carburizing at 1900°F. Direct quench coarse grain rollers had significantly lower pitting life. Pitting life increased when rollers were reheated after carburizing for grain refinement.

This paper is a result of the advent of new and much more stringent braking codes that are evolving for the braking performance of off-highway open pit mining trucks. The paper reports a series of actual truck performance tests to learn if stopping performance is predictable, to learn about the fade characteristics of the available linings, and to compare the actual brake performance to the theoretical performance. Various combinations of load, grades, and speeds were used for comparison. Results show that designing a brake system to its static K value is not acceptable, that a level equivalency test of stops on ten percent grade is not practical, and that to insure similar linings will behave similarly they must be tested.

Tests and analyses are presented on bulldozer blade oscillation configurations for improving dozing productivity. The purpose of oscillation is to decrease the ratio of tractive force to blade force, since dozing costs are so strongly dependent upon tractive force. The oscillating blade mass, frequency, amplitude, and direction of motion for optimum performance are determined using an approximate theoretical analysis. The theoretical results are compared with experimental results obtained from the literature. Reasonable agreement is obtained. Oscillating blade configurations are presented which should realize double the present dozer performance. In addition, those configurations provide complete isolation of the dozer from the inertial forces of the oscillation system. Prior to obtaining the analysis, full scale configurations for a U.S. Army D5 dozer were designed, built, and tested. The tests showed around 20% and 30% improvement with the two configurations.

A new generation of “Super-Stabilized” antiwear hydraulic oils has been developed to meet the stringent requirements of modern high-performance hydraulic systems. Outstanding performance properties of this type of heavy-duty industrial hydraulic oil include: multi-metal compatibility, “keep-clean” performance, antiwear retention, thin oil film inhibition, controlled demulsibility, and wide-temperature-range pumpability. A review of power transmission fluids used in earlier equipment designs is presented going from the “Water Age” to the “Mineral Oil Age.”

The driveline in an application can be the source of vibrations. This paper explains and gives corrective procedures for driveline vibrations caused by unbalance, torsional excitation, inertia excitation and secondary couple effect. It also briefly explains the influence of the driveline on the system bending resonance of the engine-transmission package.

Peak oil film pressure is cited as the parameter controlling the fatigue life of a sleeve bearing. Variables affecting peak film pressure, and the freedom to control them, are discussed. Bearing clearance is the variable most readily controllable, and has the greatest impact on film pressure. Through a simple design change to the conventional sleeve bearing, substantial improvements in fatigue life can be realized for any bearing alloy. Tests in both engines and bearing fatigue rigs have confirmed the validity of the theory on which the design is based. Advantages and implications of the new bearing design with respect to heavy-duty diesel engines are discussed.

Along with the increase in specific output of internal combustion engines the determination of piston temperatures in diesel engines and the possibility of influencing these temperatures has attained greater and greater significance. After a survey of the temperature conditions of pistons in non-turbocharged and turbocharged diesel engines and the various temperature measurement techniques used to determine piston temperatures, this paper will concentrate on some of the different parameters in pistons for diesel engines in the diameter range of 100 to 140 mm and will present their effects with the aid of comparative investigations.

The recent advent of small remotely piloted aircraft as tools for both military and civilian missions has set a requirement for reliable, low vibration, compact, reciprocating engines in a power range where such engines have not previously been available. A new twin crank, geared output engine is being developed to satisfy this requirement. The special feature of this engine is its very low vibration. An analysis and the resulting balance criterion that gives this low vibration is presented.

An engine for providing 10.4 kW (14 hp) with efficient throttled performance has been developed for use in a small, remotely piloted airplane. A requirement for operation at very high altitudes resulted in the choice of an oxidizer-independent, monopropellant gas generator to supply energy. One unique feature is a valving concept by which the working piston is used to actuate the gas-inlet-valve poppets. A pneumatic spring is used to provide the proper valve closing force. The exhaust is ported through the lower cylinder. Good life characteristics have been demonstrated by nearly 20 hours of ground and flight testing.

AFTER MAKING A QUICK GENERAL SURVEY of the different injection systems which have been testing for some years, the author describes a new direct low pressure fuel electronic injection system specially adapted to the two stroke engine. Very short time of about a millisecond can be obtained at high flow variation by controlling electromagnetically the balistic movement of the injector needle. The monitoring electronic control can be carried out by an opto-electronic memory or a static one (M. O. S.) by microprocessing. The performances of such system are specially interesting with regards to the specific fuel consumption decreases about 30 to 40 per cent compared with an engine fed through a carburettor. The unburnt H.C. emission level, which until now condemned the two-stroke engine, are greatly decreased.

Previous publications from The Queen's University of Belfast have described the unsteady gas flow through a naturally aspirated two-cycle engine and the most recent of these have detailed the scavenge process, the combustion model and muffler design. It is thus now possible to predict the unsteady gas flow behaviour through and the performance and noise characteristics in this type of engine with a good degree of accuracy. This paper describes a mathematical model which has been formulated to simulate the action of the two-cycle engine fitted with a reed valve due to the unsteady gas dynamic behaviour in the inlet tract and makes comparisons with measurements. A complete simulation on the computer of a two-cycle engine fitted with a reed intake valve is thus now possible.

The Robert Bosch series of In-Line Pumps currently serves engine output requirements ranging from 13 to 268 BHP per cylinder. In this family of injection pumps, the type P in-line pump is mainly applied to heavy-duty, direct injected truck engines, with power output up to 80 BHP per cylinder. Since 1962 approximately 1.5 million pumps of this type have been supplied to the field. Advanced development of the Diesel engine aimed toward increased power output and more favorable exhaust emissions have made further development of the injection system necessary. Conversely, however, the continued development of the injection system provides the possibility of realizing these improvements to the engine. As a contribution to this development, Robert Bosch has redesigned the “P” pump.

This paper outlines the problems posed to the designer of fuel injection equipment suited to engines developing from 11 Kw (15 bhp) to 75 Kw (100 bhp) per cylinder and deals in detail with the improvements made to several highly-stressed components in order to make significant increases in service life. The paper then reviews the resultant Lucas CAV range of equipment, concentrating on the Maximec pump and the associated ancillary equipment.

The influence of residual stress and retained austenite on the fracture behavior of bend test specimens of carburized steels was evaluated. The test results are part of an ongoing research effort intended to compare the relative fracture properties of alternate grades of steel and their respective standard grades having similar hardenability. In general, steels of equal hardenability and core carbon content exhibited similar fracture behavior. Compressive residual stress in the carburized case was found to significantly influence the impact fracture stress which, in turn, was correlated with impact fatigue properties. High levels of retained austenite at the surface caused the peak compressive residual stress to occur further into the case. The occurrence of residual stress peaks further into the case was not necessarily detrimental to impact fracture stress or impact fatigue properties.

Robert Bosch GmbH has been developing and manufacturing electrical equipment for automobiles for approximately 80 years and electronic equipment for over 20 years. The first section of this paper describes the beginnings of automotive electronics and their early products. The second section deals with the most important current products which include, in particular, electronic fuel injection, breakerless ignition, and the antiskid. The last part describes the development of future products which consistently use digital technology and in many cases a microcomputer. The most significant project in this series is the digital engine control to manage gasoline injection, ignition and automatic transmission.

The increased usage of electronics in automobiles, especially in critical engine control and safety related applications, makes electronic component reliability a major concern. As the automobile customer becomes more quality conscious, reliability becomes a more and more important sales factor. This paper addresses the needs for improved and predictable reliability for automotive electronics. Reliability enhancement will require improvements in packaging, testability, device design and fabrication processes. Electronic components will have to have reliability designed-in rather than “yielded-in.” There are also needs for improvement in predictions of reliability performance in the field and for alternatives to screening techniques to eliminate infant mortality. Improvement of automotive electronics reliability will require better communication and more joint efforts on the part of individual vehicle manufacturers and members of the electronics industry.

The Japanese automotive industry is greatly concerned with meeting the 1978 Japanese emission standards. Many electronic approaches are used as a powerful tool in solving the emission control problem. There are also many other examples of automotive application of electronics. This paper describes the recent development of automotive electronics in Japan.