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A methodology for assessing ground run-up noise exposure/impact resulting from turbine engine performance testing on outdoor facilities was developed. The overall methodology consists of three calculation procedures using dBA levels (measured or estimated) to predict the Day-Night Level (LDN) at any location across existing terrain. The methodology provides the analysis capability required to 1) study noise suppressor requirements in order to minimize costs, 2) locate run-up and test-cell pads, and 3) study the impact of run-up operations changes. It also provides a potential capability for assessing noise exposure from 1) takeoff power check run-ups, or 2) other (non-turbine) static noise sources.

A deterministic, cascade or network queueing algorithm is presented that relates, using a recursive formula, the passenger arrival patterns at components of any two successive stages of airport terminal-building processors as a function of the service times, service rates, and waiting times of components in the first stage and the passenger flow distribution pattern. The effects of ancillary activities between two stages are treated with a stimulus-response model; the stimulus is time before departure and the response is ancillary activity usage. An attempt to implement the model using a discrete-time flow model is described.

Loop transportation systems are studied. The standard critical link analysis is evaluated and found to be deficient in several ways. The concepts of spatial and temporal service variability are introduced and means of quantifying these phenomena are presented. A simulation model is used to assess the effects of service variability on performance or waiting times. The models presented are designed to augment the critical link analysis and to allow designers to gain a better feel for the system behavior before running detailed simulations.

The use of dynamic simulation to model the landside facilities of a modern airport offers a valuable analytical tool to the airport decision maker. Simulation technology can test and rank investment proposals by providing specific projections relating to landside congestion. This paper discusses an operating simulation that models the behavior of persons and vehicles moving through the landside systems. The output of the simulation is statistical information regarding the congestion parameters of waiting time, occupancy and flow at landside facilities. A description of how simulation outputs are validated and used in the determination of landside capacity is also included.

A requirement has appeared within the next generation of commercial aircraft for a modern engine of between 30,000 and 36,000 lb. thrust. The RB 211-535 meets it by extending the RB 211 family's thrust range downwards, and is based on the fully developed RB 211-22B H.P. system running derated. Its design retains the parent engine's proven advantages and provides fuel consumption and noise levels similar to the existing large fan engines. The derivative nature of the design ensures low risk development and service introduction, and low airline maintenance material costs. Overall, the RB 211-535 comes close to the optimum solution to the requirement.

REPLACEMENT AIRCRAFT STUDIES were conducted throughout the 1970s for the 707/DC-8/and 727-100 fleets which are expected to be largely replaced in the 1980s due to environmental regulations, rising fuel prices and other economic considerations. P&WA chose to offer a new, high-bypass-ratio, high-performance engine, the JT10D, designed at the outset to use new technology materials, processes and components plus the experience of first and second generation turbofans. Late in 1977, P&WA redirected the JT10D program toward a common core engine family to cover the thrust range from 25,000 to 35,000 pounds thrust to satisfy various new airplane requirements.

A new 30,000 pound thrust class engine requirement has evolved for commercial transport service in the early 1980's. The CF6-32, a derivative of the General Electric CF6-6D high bypass engine, is described. Both engines utilize a common core which is completely interchangeable. Economic justification is developed for the CF6-32. Using the CF6-6D mature core with an initial capability of low shop visit rate, more than offsets the performance advantage that would be inherent in a new engine tailored to the new airplane thrust requirements and available in the early 1980's.

In regards to construction equipment, there has been a rapid increase in the number of civil engineering projects undertaken in urban areas over the last ten years. Thus, necessitating further consideration of the pollution problem. Noise and vibration pollution account for a high rate (34%) of construction pollution. In regards to exhaust gas, countermeasures, different from those used against motor vehicles, were put forth to protect the health of the workers. This paper refers to current anti-pollution regulations, user needs, and countermeasures against noise and exhaust pollution, and also includes future problems.

One alternative to the problem of improving fuel consumption while reducing high exhaust emissions is the dual chamber stratified charge spark ignition engine. This paper describes the various phases of the research program now being conducted. Its purpose is to better understand the basic combustion process in this type of engine and the fundamental limitations involved. Typical results obtained in the initial phases of study are illustrated.

For more than fifty years the continuous working bucket wheel excavators have been manufactured by O&K. The development in the past decade gave on one hand the giant machines with a performance up to 240.000 m3 bank per day, on the other hand the full hydraulically driven standard types. The design of the hydraulic bucket wheel excavators with their operation and performance are described. For many opencast mines with middle or high output requirements, the hydraulic bucket wheel excavator is an intresting alternative to other methods.

An efficient computer program for general purpose dynamic simulation of two-dimensional mechanical systems named ADAMS2 Automatic Dynamic Analysis of Mechanical Systems, 2-Dimensional) is described. This program was developed along the same lines as the ADAMS [4] program for simulation of three-dimensional mechanical systems. For two-dimensional analysis this approach results in reduced execution time and storage requirements in comparison to specialized use of the 3D code.

New design analysis methods for the structural development and evaluation of earthmoving equipment have been heavily utilized in recent years. In particular, this increased utilization has focused on the use of finite element methods for analyzing stresses in structural components and the use of combined experimental/analytical modeling techniques, such as the “Building Block Approach,” for studying the system response of complete vehicles. The presence of these predictive methods has placed a new burden on test activities which support vehicle design and analysis. Properly planned tests on “reference vehicles,” i.e., existing vehicles for which new designs are needed, can play an important role in directing the new vehicle design efforts. This paper will discuss automated methods for collecting, analyzing, interpreting and handling data for effectively supporting design analysis needs.

Tunneling with a boring machine has been used extensively in the construction industry but has been virtually ignored by the mining industry. Looking for a faster and more economical way of constructing a mine slope, the Rochester & Pittsburgh Coal Company turned to a tunnel boring machine to replace the former drilling and shooting method. The results of this decision and the construction of two coal mine slopes are discussed in this paper.

A computer program has been written to help in the synthesis of four-bar linkages. With the input of the required four positions of a guided body, the computer solves for a very large number of the solutions and simplifies the user's search for the “best” four-bar linkage. The computer then examines this linkage for range of travel and discontinuities throughout this range. The program can also calculate the transmission angle range and classify the type of motion. If a graphics display is available, the linkage can be displayed and animated. The program is written with conversational input and output, including optional instructions for new users.

Enviromental Controls, Transportation, Congested Living and Utility Requirements have necessitated that Engineers seriously consider underground installation as a solution. The advent of the Tunnel Boring Machine make these installations economically feasable.

This paper presents an overview of the tools and techniques used in soft-ground tunneling. The history of mechanized soft-ground tunneling is reviewed to describe the major advances leading to the development of the modern tunneling machine. Major subsystems of modern machine boring are then described in some detail, including excavation, support, and materials handling. The paper concludes with a summary of the current state-of-the-art of mechanical boring, followed by a look at near-term innovations and their impact on future machine boring.

A large contractor expresses his feelings and some facts on the type of machinery the industry is producing today. The reliability, availability, and longevity are not being built into the present construction machine.

The quality of a product is as perceived by the user and includes the net effect of the quality of the original product and of available product support. Engineering objectives should include improvement of support capabilities, regardless of the exquisiteness of the design.

Earthmoving equipment manufacturers need to concentrate on machine service related problems which have been identified in the past ten years. These service problems are grouped into routine maintenance, design, safety equipment, component reliability, tires and export machine problems. Specific requirements are outlined and recommended design objectives are identified. The conclusion is equipment manufacturers need to concentrate on designing machines that reduce service and maintenance cost as well as provide simplicity of operation and maintenance while simplification for utilization in export markets is a common requirement.

An analytical model has been developed that provides a valuable addition to the tools available for practical exhaust system design. Correlation with experimental results has been improved by including the effects of such factors as temperature gradients, complex elements, higher order modes, and source impedance. The model can be used for specific design problems as well as general parameter studies to maximize exhaust system attenuation within a given volume.