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This paper outlines an approach to highway transportation research which considers the interrelationship of the major subsystems. It describes the framework, the variables, surveillance techniques, and new vehicle instrumentation. A model is described which serves as the basis for field testing and subsequent mathematical analyses. Surveillance systems including instrumented vehicles, ground, aerial, and space platforms are required as components of a real-time system. A research project, designed to evaluate driver stress, is discussed and sample computer data are shown.

The described vehicle traffic simulator is designed to facilitate analysis of traffic flow and to experiment with postulated traffic control systems. It offers users a large amount of flexibility in specifying network, intersection, vehicle, and control parameters. The logical flow of vehicles, as well as much of the control system, is preprogrammed. Vehicles varying in size may change lanes, turn, change velocity (including reaction and acceleration delays), and merge. Inputs may be varied, turns may be eliminated, and vehicles may be routed through the network. The user supplies the geometrical characteristics and input information unique to his particular network in data cards for the program. Some applications to real traffic networks (including a validation procedure) and some simple control experiments are discussed.

Two digital computer simulation models of traffic operation and control have been developed -- a microscopic single, signalized intersection model, and a macroscopic signalized intersection network model. The paper describes the general features of the simulation models, presents summary data pertaining to the validity of the models, and briefly reviews research results from studies of traffic signal system operation made with the models.

While a number of important attempts have been made to describe characteristics of an intersection purely in mathematical terms, the most fruitful research from a practical standpoint has utilized simulation. This paper reports the results of research in which a four-way stop intersection was simulated on a digital computer. Inputs to the program were based on field studies at three intersections in metropolitan Atlanta using mathematical models and Monte Carlo techniques. Field data were taken with the aid of a spring wound Esterline-Angus 20-pen event recorder and time lapse movies. The simulation model was used to study the effectiveness of the four-way stop at various approach volumes and turning movement combinations. Results of experiments conducted on the simulation model are given by graphs showing the relationship between traffic volumes and average delay, per cent delayed, and average queue length.

Vehicle traffic congestion is one of the serious problems facing municipal administrators. The search for increased efficiency has led to the development of traffic engineering as a science. The digital computer as a traffic engineer's instrument is relatively new, but appears to be a natural successor to analog systems, which have in turn sprung from fixed time systems and noncoordinated devices. Today's computer systems are the first to link all the elements of a closed-loop automatic control system; namely, information gathering, decision-making, execution, verification, and evaluation. In particular, the system at San Jose has shown that a computer system can be readily adapted to handle different control techniques, and give almost immediate feedback in concrete terms. A system of measuring stops and delay, developed at San Jose, can be used to evaluate traffic in both a microscopic and macroscopic sense.

The image of a large corporation in today’s technical world is, in many instances, dependent upon its interest in the innovative process and adaptability to change. Air pollution poses a serious threat to this country. In an effort to implement recommendations for the control of automotive air pollution, the more important findings of a government study group (fully reported in “The Automobile and Air Pollution: A Program for Progress”) are summarized. The development of effective means to infuse new ideas into the automotive industry is discussed.

An integrated circuit regulator for automotive alternator systems has been developed. It may be used either as a separately mounted unit or incorporated within the alternator. Consideration is given to the choice of micro-circuit, the type of transistors, and the method of substrate assembly. The design features and operation of the circuit are discussed.

This paper presents a new concept and technique for solving the problems associated with the prediction and control of flight component failures which are attributed to contamination of the power transmission fluid in the servo actuating subsystem. Basically this technique assumes that these failures are probabilistic. Mathematical models are then established and comparisons made between calculated and measured values of contamination in a system to determine the degree of acceptability of the fluid.

The automotive gasoline engine has been under heavy attack as a source of air pollution, and is now the subject of a very large program of research and development to reduce its undesirable vehicle emissions. The quantity of emissions that can reasonably be tolerated in different areas of the U.S. is presently unknown because of lack of information concerning air movements and air quality standards for man and plants. It is important that this information be made available as quickly as possible because the cost of emission controls of all types will rise rapidly. With rapidly rising costs for air pollution control from all sources, cost-value analyses are urgently needed for economy. Major reductions of the undesirable exhaust emissions of present powerplant systems have been made during the last few years and will continue to be accomplished, under the impetus of air pollution requirements and regulations.

The new SAE J992 establishes minimum service brake system performance requirements and specifically pertains to vehicle stopping ability, pedal force requirements, and brake stability of new vehicles. Testing for SAE J992 includes procedures that were taken from applicable sections of the truck and brake system road test code, SAE J786 dated 1962. This paper compares SAE J992 and J786 in the areas of test instrumentation, preburnish check, burnish, water recovery, and efffectiveness requirements. Although SAE J992 is briefer than previous test procedures, it is a valid determination of minimum stopping ability, a check on the initial fade due to heat, and a measurement of the water recovery characteristic. The minimum performance values specified are quite stringent for all types of trucks and buses.

The revised Passenger Car Road Test Code, SAE J843a, provides a test procedure of improved reproducibility and a high degree of severity. The new report, SAE J937, performance requirements, are stringent and have contributed to the up-grading of passenger car brake systems and individual components.

The author reviews work underway to expand current brake test standards. Initially he discusses the Pennsylvania procedure for testing original equipment and aftermarket brake linings. Although these tests are similar to SAE tests, current SAE procedures have to be expanded so they can be used for component approval, other than linings, in order to realize full capabilities of existing brake test specifications. Subcommittee 7 has assigned working groups to develop special procedures in the areas of partial system performance, passenger car durability, brake structural integrity test, truck-trailer performance test, and car-trailer performance test. The work being done in these areas is reviewed. It is obvious that constant up-dating of specifications is a necessity in order to reflect the state-of-the-art as accurately as possible.

The Allison 250 turboprop program is reviewed including engine characteristics, the development program, FAA certification, and development to higher power ratings. Market and installation programs are reviewed including general aircraft turbine engine trends, turbine engine market potential, and a discussion of the justification and merits of small turboprop aircraft. Various 250 turboprop installations are discussed.

Constant frequency a-c electrical equipment, consisting of a hydraulic constant speed drive powering an a-c generator, is now available for consideration on business aircraft. This system can provide significant weight savings over other types of electrical systems and provides the same high reliability and good growth potential that has been realized on larger military and commercial aircraft since 1946. The weight savings that can be attained is particularly appealing when the aircraft includes an auxiliary power unit (APU) that can be used to provide power for pneumatic or hydraulic main engine starting. This eliminates the need for the heavy d-c starter/generator and results in lower overall aircraft weight.

The problem of aircraft noise is reaching critical proportions, with the ever-increasing number of jets and the coming introduction of the 747 and SST. The communities surrounding airports are becoming more and more intolerant of this noise. Although engineering technology will solve some of the problem with advances in engine design, the final solution rests with the federal government. Only on the federal level can effective noise standards be promulgated and applied to all aircraft through the certification process. This solution is discussed in detail.

This paper discusses the considerations and procedures of aircraft maintenance during the early period known as the warranty period. It highlights what warranty is or is not and the various aircraft and component warranties, as well as advantages and disadvantages. The purchase of a new piece of equipment for the fleet always presents the question to the maintenance chief of how to keep it flying and what will be the cost of operation. Warranty programs in general and the advantages offered while easing the burden of claims requests for the buyer and the manufacturer are discussed.

Increasing air traffic has produced an increase in midair collisions. This paper describes the airborne collision avoidance system (CAS), which is intended for use by large aircraft. It also describes the Dinade CAS, intended to be installed in small aircraft. In addition, the combination of the Dinade interrogator with a weather radar to conserve capital investment, space, weight, and power consumption, is discussed.

Light aircraft that encounter the trailing vortex system generated by heavy transport aircraft can experience high roll rates, loss of altitude, and large structural loads. Envelopes of vortex system velocities, duration, and movement for various wind conditions have been determined. Specific operational procedures for the take-off, landing, and enroute phases of flight are suggested to enable the light aircraft pilot to avoid the wake turbulence of heavy aircraft.

This paper discusses the work that the Engineering Div. of Goodyear Aerospace Corp. has been conducting in energy-absorption and how this has been applied to new concepts in fuel containment. The discussion includes various qualitative test methods and compares the test values of the material being investigated to standard fuel tank materials. Hopefully, these values will suggest new design approaches and test procedures for the improvement of fuel tanks, both in crash-resistance and puncture sealing ability.

Present fuel flow measuring systems for medium priced aircraft lack the accuracy needed for efficient flight planning and cargo weight scheduling. They also lack the means for totalizing the measurement signal to provide an accurate measure of fuel consumed or fuel remaining. A new fuel management system has been designed to use a turbine meter to measure fuel flow. Since the measuring instrument provides a digital output, flow rate can be totalized by means of a pulse counter. Therefore, in addition to rate indication, the pilot has an accurate total of fuel consumed or fuel remaining at his disposal. This paper discusses the advantages and disadvantages of existing systems and contrasts them with the turbine meter system. It also discusses fuel density changes due to temperature and fuel type and how they affect the measuring system in both piston and turbo-type aircraft.