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A reliable product is essential to the automotive industry. Experimental stress analysis complemented by life testing, as shown in this paper, plays a vital role in developing sound brake and suspension components. Testing techniques to provide rapid solutions are employed on a variety of structural members. The application of simple principles with regard for limitations provides solutions to a multitude of endurance problems. Rules are given to guide the beginner and to refresh the memory of the experienced test and development engineer. Careful use of the methods shown coupled with attention to the principles expounded will result in reliable designs.

The Impact Sled, a full-scale laboratory facility which simulates vehicle accidents, has been in use at the General Motors Proving Ground since late 1962. This paper describes the facility and supporting instrumentation, and reviews some of the many types of tests that were run in the first year of operation. These range from tests of complete vehicles loaded with passenger dummies to tests of single components such as seat belts, seat adjusters, door locks, and windshields. This new research tool, which produces results comparable to those of the classical barrier impact test, has proved to be a valuable and versatile addition to the automotive testing facilities at the Proving Ground.

This paper presents those practices of hand soldering that must be carefully controlled in order to obtain a reliable soldered connection. So that the proper perspective may be developed, the evaluation of the NASA hand soldering program and the associated documents used for implementation are discussed. Material selection, cleanliness, lead preparation, heat management, solder application, and flux removal are explained with respect to their relative importance.

Application of electron microscopy to the study of fractures and fracture mechanisms is reviewed. Static fractures and the fracture of multiphased alloys have been studied, and significant information obtained. Striations on the fracture surface are associated with fatigue crack propagation and are directly related to crack growth rates. Various factors such as strength level, corrosive media, and second-phase particles are known to influence the appearance of the striations under the electron microscope. Since the appearance under the microscope of each type of fracture is quite unique, electron microscopic fractography is also an aid in service failure analyses.

This paper presents a summary of the development of the “Chambered Pipe” silencing concept. Present trends of automotive design dictate a change from conventional mufflered systems. One such trend is toward high performance in low profile bodies, while another related trend is toward compact cars. By approaching the silencing problems from a more theoretical basis, small diameter acoustic elements of low pressure drop have been developed to satisfy the exhaust system requirements of modern automobiles. The paper discusses the theoretical basis for the “Chambered Pipe” silencing system approach and shows resolutions of actual test data to the theoretical analysis. Test data showing the effect of optimum placement of silencing units in actual hot gas flowing systems are presented and discussed. The advantages in space required for installation, sound characteristics, low power loss, strength, weight, and better life are explained.

The great spurt in outboard motor industry has brought with it an increased demand for economical operation, adequate power, dependability, and other features to meet the needs of light craft owners. The 4 cycle gasoline outboard described here promises to fulfill all these requirements while solving major health problems such as water pollution and exhaust irritants. In addition, maintenance has been greatly simplified, and styling has been designed to satisfy modern trends.

Abrasive machining of parts such as engine blocks is a fast growing process that promises to replace many applications of planing, milling, and shaping. Its economic advantages, its simplicity, its speed, and the quality and attractive appearance that it gives to parts have been proved. This author suggests that only attitudinal changes in the psychological climate of design and engineering are needed for popular adoption.

The principle cause of objectionable wind noise in the modern automobile is small air leaks in certain critical areas. The aerodynamic shape is insignificant in overall wind noise. The critical areas in order of importance are: 1. Vent window and door to “A” post sealing from the roof rail to about a foot below the beltline. 2. “C” post area at beltline. 3. Upper rear of front door area. 4. All other areas from roof rail to a foot below the beltline. Conclusions reached after extensive testing show that wind noise can be eliminated by good sealing about the doors and windows.

The reasons for and the design constraints associated with design for in-flight maintenance for manned space missions are discussed. Analytical techniques used to define problem areas and design experience derived from several current programs are presented. It is concluded that advantages of an in-flight maintainable system justifies the additional design effort required to achieve such a system.

An overview of composite structure required for manned orbiting space stations is presented. Following a brief introduction of typical configurations and major subsystems, the major structural areas requiring composite structure and their particular functions and requirements are discussed. A summary weight breakdown is presented to assess the dependence of launch weight on these areas. To illustrate, the primary wall composite structure is presented in detail. The design interplay of boost, pressure, meteoroid, radiation, and thermal control requirements are presented. Resultant composite structure for each remaining major structural area is presented in summary form with a brief description of typical design compromises required.

Preliminary work in the area of fiberglass composites for space tankage has indicated a high potential. The major advantage is the structural efficiency. Recent development programs have demonstrated the applicability and practicality of the system on subscale bases. Extension of these basic data reveal that substantial weight savings can be realized with fiberglass tanks over those of aluminum, especially for the large diameters contemplated. Based upon the same criteria, titanium compares favorably with the fiberglass with regard to structural efficiency. The major advantages and problem areas of a fiberglass composite structure are outlined and discussed in the paper.

The factors influencing the selection of a preferred space station system concept are briefly described; and the critical considerations that influence the selection of orbit parameters, crew parameters, and logistic support requirements are discussed. It is concluded that a high level of effectiveness can be achieved but will require careful design of each element of the system and maximum use of human performance capabilities to achieve the necessarily high reliability goals.

This report discusses the application and rating factors responsible for the high energy conversion efficiency of the natural gas engine which makes the low operational costs possible. Two major factors determining size of engine are the amount of horsepower needed and the environment in which the engine will be working. Although shaft power from natural gas engines can economically drive air conditioning compressors, efficiency can be increased through recovery of rejected engine heat that is alternately used by devices such as compressors and generators.

Power requirements for driving hydraulic pumps on utility vehicles are increasing while overall cost and weight restrictions are becoming more acute. Improvement in capacities of SAE side mount power take-offs with provisions for direct mounting of pumps would be very desireable in future trucks required by the utility industry.

The transportation of fluids by tank truck has grown to rather large proportions. This is probably largely due to the flexibility of the truck in general, which in turn, is enhanced by the use of PTO driven, truck mounted, pumps that economically and quickly take on and discharge the load. Because of the wide range and varying conditions of materials handled, as well as other varying conditions, many problems exist. This paper deals with some of the most usual problems encountered. It is not intended to be a complete design manual for all PTO driven fluid transfer pump systems, but it should give the system designer a certain basic insight into the aspects which must be considered and properly handled.

Current positive crankcase ventilation systems were evaluated for their performance difficulties and their effects on fuel and lubricant requirements. These systems promote the formation of deposits in the carburetor and cause corrosion in the crankcase. Carburetor fouling can be minimized by an effective detergent in the fuel. Engine corrosion can be minimized by the use of high quality lubricants containing balanced additives of high buffering capacity. The performance difficulties associated with the malfunction of these systems may be minimized by adequate maintenance.

Positive crankcase ventilation (PCV) is now standard equipment on all new automobiles. This paper presents data on the influence of oil quality and drain frequency on the maintenance requirements of these devices. The result of system malfunction on engine deposit formation in the field is also discussed. Engine age, oil age, and oil quality are shown to be important factors affecting the time to PCV valve malfunction. A multicylinder laboratory engine test has been used successfully to predict the valve plugging tendencies of lubricants in field service.

The replacement of clutch discs in vehicles that operate under stop-and-go operating conditions represents a bother-some and sometimes major service problem. As a means toward alleviating this situation, Eaton Manufacturing Co. has developed a magnetic powder coupling which can be used to replace the manually operated dry disc clutch located between the engine and transmission of multistop vehicles. This paper describes the design, development, and test installation of the magnetic powder coupling unit in medium and large range vehicles.

An analysis is made of power sources available in undeveloped areas for portable radio communication and strategic village needs. In both instances reliability, simple operation, minimum maintenance, and low cost are prime considerations determining power source usage. For short missions, a rechargeable battery is most useful whereas for missions of longer duration a foot-powered generator with rechargeable battery is more attractive. For remote undeveloped areas the optimum power system is the foot pedalled generator charging a lead-acid battery through a modified automotive generator.