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Fly-By-Wire offers the designer flexibility in mechanizing the manual flight control system and makes possible potential CCV performance benefits because more complex functions can be implemented. The full potential of FBW and CCV can only be achieved by incorporating these concepts in the initial design phase of a new airplane. Greater benefits are obtained in several areas when applying FBW and CCV simultaneously.

An exploratory definition study has been conducted for an Advanced Fighter Digital Flight Control System. The principal objective was to derive and evaluate custom multimode control laws, related displays, and multichannel digital fly-by-wire implementation schemes for advanced Air Force and Navy fighters. Study results show that a triplex flight control system provides the lowest weight, the best maintainability, and the lowest cost of the candidate configurations considered. Results also indicate that mission-oriented flight control laws integrated with compatible displays and controllers can provide enhanced mission effectiveness and reduced pilot workload. It is recommended that the concepts analyzed and simulated during this definition study be implemented and evaluated by flight testing.

The design and operation of highway trucks in Europe is subject to legislation which is more detailed and restrictive than in the United States. The operating environment and consequently the market preferences frequently differ from those in North America. This paper discusses the important European legislation and marketing factors affecting truck design and describes the major features of a new range of heavy duty trucks designed primarily for operation in Europe. Some of the differences between European and North American highway trucks are also reviewed.

Approaches to the development of improved high temperature engine materials are reviewed. Emphasis is placed on emerging materials technologies and their potential benefits to aircraft gas turbine engines. Advances in materials processing technology are considered also, with emphasis on areas of potential cost reduction. This review also examines a changing approach to the selection of turbine engine materials technologies for future development. This changing approach places greater emphasis on the overall economic benefits to the aircraft system rather than improved engine performance.

A discussion regarding experiences with integrally-cast compressor and turbine components during fabrication and testing of four engine assemblies of a small (29 cm (11½ in.) maximum diameter) experimental turbojet engine design for an expendable application is presented. Various operations such as metal removal, welding, and re-shaping of these components were performed in preparation of fulls-cale engine tests. Engines with these components have been operated for a total of 157 hours at engine speeds as high as 38, 000 rpm and at turbine inlet temperatures as high as 1256 K (1800° F).

The re-evaluation of the brake blocks part of the “S” cam foundation air brake system established new understanding of component variation and interactions on performance. Each of the significant components must be understood and controlled to obtain desired performance consistency. The simple “S” cam brake is actually a complex system of variables requiring cautious evaluation.

Seat belt use inducing systems and seat belt use counting systems were installed in fleet vehicles of the Automobile Club of Southern California. The results were: 1. Mean group seat belt use for three use inducement systems were sequencing system 77%; ignition interlock system 86%; and speed limiting interlock system 81%. 2. There was no significant change of seat belt use for any of the three inducement systems according to time of exposure. 3. There was a significant difference between previous no system seat belt use (mean 24%) and no-system seat belt after exposure to the use inducing system (mean 49%). 4. The vehicle drivers were given a questionnaire at periodic intervals, the results of which indicated higher self-reported than actual seat belt use. Also specific confusion, inconvenience and discomfort factors were identified and rated. The conclusions were: 1. use inducing systems cause a significant increase in seat belt use of fleet vehicle drivers.

IN 1973, AN EXPERIMENTAL C.O.E. class eight highway vehicle was designed and built by Kenworth Truck Company to evaluate market impact generated by a unique looking vehicle. Various design aspects as related to driver comfort and associated component development are presented. To provide separate sleeping accommodations for two people, total cab height from current production models was increased by 22 inches. This increase was also used to develop a roof contour with esthetic valve and moderate air flow characteristics to the extent possible. In addition, a brief summary of actual road testing is presented.

This paper presents equations for determining the convective heat transfer coefficients of solid and ventilated disc brakes. Analysis of data indicates that the cooling capacity of a ventilated rotor is sharply reduced at lower speeds, and most cooling is provided by the increased surface area. A general relationship derived from road test data is presented that yields the heat transfer coefficient for both disc and drum brakes of commercial vehicles.

The suitability of using unleaded gasoline in military and commercially designed equipment located at four Army installations has been evaluated over a two-year period. A total of 3007 vehicles were monitored during the evaluation for maintenance and performance problems. This paper presents information on vehicle octane number requirements and octane number increase trends measured on a selected group of vehicles during the evaluation period. Details of the fuels used, vehicles tested, test procedure and results are discussed.

Lower temperatures at the sliding interface of a disc brake will reduce thermal wear and fade tendencies of friction materials. One method for achieving these lower temperatures is to improve the thermal design of gray cast iron discs. The purpose of this investigation was to study design improvements of brake discs for trucks. To accomplish this objective, an analytical thermal model was developed. The model employed the lumped parameter approach, in which the disc was subdivided into a number of small volumes. The model specifically simulated disc temperature response during 80.5 km/h (50 mph) fade tests performed on a dynamometer. The thermal model was correlated with test data to verify and improve its accuracy, and then utilized to evaluate effects of geometry changes. Results showed that mass concentration in the disc faces yields lower temperatures at the friction interface through 10 successive snubs.

Because of the increasing use of rubber formulations and plastics by the automotive industry, analytical methods are continually being sought for quality control and receiving inspection. The application of the thermal analysis technique, known as thermogravimetry, to the problems of fast quality control analysis is discussed. Specific examples in the areas of relative thermal stability, analysis of additives, and compositional analysis of formulations are presented.

The application of Proton and Carbon-13 Nuclear Magnetic Resonance Spectroscopy to the analysis of selected automotive plastics is discussed. Six nmr spectra are presented and the chemical shift values assigned to structural features for each polymer. The utility of nmr analysis for the characterization of organic polymers is illustrated by the application to the identification of polycarbonate thermoplastic and a polyurethane elastomer and to the determination of stereochemical configuration of poly(methyl methacrylate).

The influence of selected engine oil, fuel, and driving schedule variables on combustion chamber deposits and octane requirement increase (ORI) has been investigated during vehicle fleet tests with late model cars. Greater octane requirement increases occurred with: (a) an engine oil containing bright stock compared to an engine oil without bright stock, (b) an unleaded fuel which contained a polymeric detergent-dispersant additive with a large amount of carrier oil, compared to other unleaded fuels with conventional additive packages, and (c) customer-type driving compared to rapid mileage accumulation on a chassis dynamometer. Octane requirement increase was not affected by: (a) lead content of the fuel; or (b) ashless engine oil compared to a conventional ash-containing oil. All of the ORI with unleaded fuel can be eliminated by removing the combustion chamber deposits, and about two-thirds of the ORI is caused by deposit accumulation in the end-gas region of the chamber.

Two successive surveys and round-robin interviews were conducted to determine if there might be in the offing for automobiles an alternative engine which would exhibit low emissions meeting the most stringent requirements. Comparison between engines were couched in terms of selected “acceptability factors” which went well beyond emissions, alone. The overall acceptability was evaluated considering emissions, customer requirements for an engine, manufacturers' requirements for an engine, and engine efficiency and fuel versatility. An attempt was made to establish a time scale as to R and D requirements and eventual production. Comparison of all engines was made with equivalent pre-control Otto cycle engines as the standard. Alternative engines were deemed to be any power plant that was not based on spark ignition Otto cycle engines, or diesel engines. The remaining heat engines largely used continuous combustion as the heat source.

In recent years, several programs have been conducted at the Ethyl Research Laboratories in Detroit, some in cooperation with a major oil company, to measure the value of lead antiknocks in fuels for European cars. These heretofore unpublished studies show: 1. A positive lead road bonus. 2. Tetramethyllead (TML) is more effective than tetraethyllead (TEL). 3. The lead road bonus increases with engine operating severity. The lead road bonus is defined in broad terms as a combination of three effects - lead-in-fuel, fuel sensitivity, and engine deposits. The engine-deposit effect is not of major significance in European cars. Much of the confusion over the value of lead antiknocks in European cars and fuels in recent years can be attributed to improper definition of the lead road bonus, at times coupled with inappropriate rating conditions and limitations in fuel design. The importance of these studies is significant in view of the trend toward smaller cars.

This paper discusses lean burn engine concepts for meeting emission standards features versus the use of an oxidizing catalytic converter for HC and CO control. Purely theoretical considerations indicate that thermal efficiency and therefore fuel economy should be improved by lean operation. Whether this system will be used is dependent on the Federally regulated auto emissions standards.

A review has been made of anomalies that exist in the changes in octane requirement of recent model cars operated for several thousand miles using unleaded gasolines and SE quality oils. A number of laboratory multicylinder engine tests have been conducted to elucidate possible reasons for some of these anomalies. These tests have uncovered mechanical variables that can produce relatively rapid changes in the octane requirement of an engine and octane requirement differences between engines of the same make and model, operated on identical combinations of gasoline and oil. Two of the more important variables are the initial octane requirement and the amount of oil migrating to individual cylinders in the engine.

Methylcyclopentadienylmanganese tricarbonyl (MMT) while originally marketed in the late 50's and early 60's as a secondary antiknock to leaded fuels, is presently being marketed as a primary antiknock targeted for the EPA required lead-free gasoline grade tailored for use in catalyst-equipped vehicles. This paper reviews and discusses new information related to the effect of manganese gasoline additives on the performance of catalysts, regulated emissions, and several currently unregulated emissions. In addition, estimates of human exposures to automotive-generated manganese particulate and the toxicological characteristics of manganese are discussed as they related to an assessment of the potential public health consequences should manganese additives come into widespread use. EPA's position regarding the use of manganese additives is presented and discussed.

This article outlines the design objectives for a light weight economical five-speed manual transmission for the subcompact, compact, and intermediate size passenger cars. Major features presented are a die cast case design allowing assembly of gears through rear opening, internal linkage, use of needle bearings and an overdrive cruising gear. See Fig. 1.