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The general subject of turbine engine thrust management includes the selection and setting of engine thrust. Flight manual information available to the operator of turbine powered aircraft defines the methods for selecting thrust levels with relation to a predetermined minimum airplane performance standard. The logical selection of thrust level to be used requires an understanding of the resultant effect on engine parts life as well as the effect on operating economics.

Current jet fuel prices of twice the 1972 level have significantly changed the characteristics of airplane design for best economy. The results of a contract with the NASA Ames Advanced Concepts and Missions Division confirmed the economic desirability of lower design cruise speeds and higher aspect-ratio wings compared to designs developed in the by-gone era of low fuel price. Evaluation of potential fuel conservation for short-haul aircraft showed that an interaction of airfoil technology and desirable engine characteristics is important: the supercritical airfoil permits higher aspect ratio wings with lower sweep; these, in turn, lower the cruise thrust requirements so that engines with higher bypass ratios are better matched in terms of lapse rate; lower cruise speeds (which are also better for fuel and operating cost economy) push the desired bypass ratio up further.

Short-haul air transportation is one of the most challenging of all modes of transportation. The short-haul passenger market represents approximately 40 percent of the total U.S. domestic market. This market can be classified by passenger density. A Douglas study, funded under a NASA contract, is reviewed. This study indicates potential means for successfully meeting the challenges in the market with under 500 daily passengers. Initially, the market is investigated and realistically defined; then aircraft requirements that are economically viable and environmentally acceptable are established to satisfy the market. To meet the challenges of this market, the need for economic viability and environmental acceptability requires the careful balancing of performance, technology, and design-to-cost concepts. A general aviation manufacturer participated in evaluating design-to-cost options and three airlines provided guidance for operating realism.

Recent developments in centralized lubrication systems have made them more compatible with the operational demands of the construction industry. This system delivers the correct amount of lubrication to each bearing, can warn the operator in the event of a lubrication failure and directs maintenance personnel to the problem area during a scheduled downtime. It has a wide variety of pumping methods, controls and monitors. Safety of personnel, continuous lubrication, reduced downtime, reduced usage of lubricants, longer machine life and higher profits are the results of a good lubrication program.

In the past, there was little need for changes in machinery design specifically for surface mining. However, the requirements imposed by land reclamation legislation since the 1940s present problems that cannot be handled readily by conventional equipment. For the long run, new types of equipment should be considered. In the meantime, research efforts should be devoted to redesigning, enlarging, or modifying existing equipment.

The paper begins with a brief history of Colony Development Operation, followed by an overview of the planned commercial mine and plant complex which includes artists' conceptions of the designed layout. The four basic areas of a commercial complex; mining, crushing facilities, processing facilities, and processed shale embanking and revegetating, are presented. The commercial operation, two-bench, room-and-pillar mining system design is described in detail. The mining cycle of drilling, blasting, loading, hauling, scaling, and roof bolting is discussed, as well as the mobile mining equipment which is being designed and will be utilized. Some of the detailed Colony pilot mine engineering testing programs are then introduced, and their effect on the commercial mining of oil shale is enumerated.

The air film industry, although relatively new, has been widely accepted by manufacturers of heavy equipment. The unique ability of air film equipment to practically eliminate friction and facilitate the movement of heavy, bulky items economically has contributed to the evolution of many new manufacturing techniques. THIS PRESENTATION WILL ATTEMPT to provide a condensed survey of the utilization of the air film material handling principle in the production and assembly of heavy equipment. This method of load movement, introduced into general industry in the late 1960s, is providing a new avenue to the designer of heavy duty assembly and production equipment. The fundamentals of the air film principle will be reviewed and a survey of current implementations presented. The latter method is used as a graphic means of illustrating the air film principle of load movement as applied to heavy equipment.

This paper evaluates some popular management techniques generated by social scientists and considers some lesser known findings more specifically related to the engineering profession. The author indicates both for engineers and engineering managers, methods for discovering and dealing with individual psychological needs.

Temperature buildup tests and load deflection tests have been conducted on six tires; three sizes with one bias and one radial ply carcass construction per size. Temperature buildup curves are given for each tire at various conditions. Curves of load versus deflection are shown for each tire during both loading and unloading. Loss energies occurring during the loading-unloading cycle are tabulated.

This paper describes a technical forecasting program that was used at the John Deere Dubuque Works' Engineering Department and-even though we have not proven its effectiveness-tells you why we think it works. It also tells construction machinery will probably be like 20 years from now.

The application of all-wheel drive vehicles to the desert environment is not new or unique, but model changes occur that incorporate improvements of components or manufacturing techniques. This paper deals with one specific six-by-six power-shift model that was first marketed in 1973. (“Six-by-six” refers to a six-wheel vehicle with all six wheels capable of transmitting power from the engine.) A description of major components and how they are matched may be a useful tool for future designs. The cooling system and tires are the major differences in the desert six by six, when compared to the conventional all-wheel drive units applied to the United States construction market. These are discussed in detail.

In the overall concept of a motor grader, many requirements must be established and met to produce a machine that will efficiently perform the work for which it was intended. Some of the major design concepts, features and specifications of the new John Deere JD770 Motor Grader are discussed in this paper.

The current energy shortage, coupled with the presence of oil on the north slope of Alaska, has placed trucks in an unusual operating environment. They must be manufactured from materials that can withstand temperatures of -65°F (-54°C), provide a comfortable environment for the driver, and perform efficiently.

Review of various construction, equipment and organization factors considered in the design of new plant facility for fabrication of prototype earthmoving vehicles. Emphasis on eliminating existing problems and maximizing plant efficiency.

An elementary engine alarm system is described which may have had some effect in reducing cylinder head damage. The claim is advanced that many problems encountered with the early system in reality contain hidden beneficial aspects, but the certitude of this is left unresolved. A more complex system is described which can monitor oil levels and contains fault-detecting circuitry. THE PURPOSE OF THIS PAPER is to describe the results obtained during some attempts to gain extended engine life by means of warning and information systems. The primary impetus for this was a belief that engine cylinder head failures on the Iron Range of Minnesota were excessive. While the primary cause of cylinder head failure is believed to be overheating the secondary cause-the basic reason for the overheating condition-is generally more diffuse in nature. Data will be presented on cylinder head mortality rates since the introduction of the initial rudimentary alarm system.

Synthetic lubricants are not new breeds of fluids which were suddenly developed because of scarce petroleum oils. They have been available for many years and utilized as lubricants for diversified ranges of specialized applications. These specific fluids were developed with tailored physical and chemical properties best suited to the severe demands of equipment operating under wide temperature ranges and other hostile environments. This paper will cover applications on earthmoving equipment such as gear lubrication, hydraulic and torque convertor fluid, engine oils and greases exposed to wide temperature ranges and, especially, low temperatures. Large, heavy duty earthmoving equipment is being exposed to very low temperature environments, as low as -65°F in some remote areas of the world. This demands lubricants that have better low temperature properties than found in petroleum base types.

The results of over 600 braking tests carried out on large mining trucks are presented in this paper. The tests were made over the past five years at mine sites in British Columbia on dump trucks having load capacities ranging from 35-200 tons. All tests were made with the vehicles fully loaded operating on downhill grades varying from 6-10%. Stopping distances were measured from the point of application of the service brakes from various initial speeds. The results are adequate, in some cases, to permit extrapolation of the observed values to indicate a likely “runaway” speed of the truck in the event of failure of the regenerative or other auxiliary retarding system.

A modified Front End Loader has been equipped with a hydrostatic elevating attachment that turns, mixes, and aerates as it windrows solid waste. In mechanizing nature's composting process, time required to compost is reduced and the results are an economical means for organic solid waste disposal. Three types of solid waste applications are highlighted: Municipal Landfills, Animal Waste, and Sewage Sludge.

Oil analysis has been used for a number of years to determine the condition of lubricated machinery, and to predict failures from excessive wear of lubricated parts of the machine. The principal technique in use up to the present time has been spectrometric oil analysis. This technique is based on the concept that as a part wears, minute quantities of wear material enter the oil and are dispersed throughout the whole lubricating system. A sudden increase in the amount of a metal in the oil indicates that some part made of that metal has started to wear. The technique has been successful in several major applications, principally in the railroad industry on diesel locomotives and in connection with the monitoring of aircraft engines. The technique is widely used and has provided warnings of failures before they have resulted in catastrophes. Often the cause of the failure can be corrected before serious permanent damage is done to the machine.

The historic development of product design analysis is reviewed to highlight the fundamental needs of collecting and analyzing field service histories. These needs and other criteria of an analysis procedure which reduce product development time and costs are discussed. The paper shows how a three level field service history analysis procedure can fulfill the design analysis needs of product engineers.