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The new high-safety glazing is superior to that currently in use. The total thickness is reduced by half, which results in greater lightness, flexibility, and reduction of the effects of inertia. It offers very high resistance to rupture and penetration caused by external impacts by small projectiles and even repeated impacts. In the event of breakage by these exterior impacts, total visibility is maintained. In the event of internal shocks of light or moderate energy, the high resistance to rupture combined with light inertia and great flexibility means that the human tolerance limit is never reached. When these internal shocks are of high energy, progressive deceleration and considerably heightened resistance to penetration is evident, compared to the high-impact sheeting of ordinary thick glass as prescribed by USAS Z26.1. The danger of cuts is practically eliminated and the guillotine effect is totally eliminated.

The exchange of energy between bodies involved in an impact depends upon the elastic properties of the bodies and, owing to the sequence of the dynamic reaction during the impact, upon the shape of the impact bodies. In the case of ball and plate, the conditions in this respect are extreme ones. With regard to the forces of reaction caused by the impact of a passenger against the fastened windshield, the different reactions of the various types of safety glass have to be taken into account. In particular, the forces of reaction and the reaction times occurring must remain within human tolerance limits. New windshield systems are presented which take into account the human tolerance values of the cervical spine.

A versatile acceleration facility is described which accelerates and decelerates a sled or a modified automobile on its own wheels. The same propulsion and snubber systems are used for both the sled and the vehicle configurations with less than an hour required between runs. Accelerations and decelerations up to 60 g, velocities up to 60 mph, onsets of 200-2000 g/sec, acceleration distances up to 10 ft and deceleration distances up to 6 ft are available with excellent reproducibility. Extensive safety features for the operating personnel are provided.

The response of a restrained car occupant to deceleration patterns recorded at barrier impacts with European compact cars is studied by using a simple model in an analog computer. In order to illustrate the general influence of restraint characteristics and slack, the occupant is defined as one solid mass and restraints are characterized by linear load-elongation functions of different stiffness. Various degrees of slack are introduced by delaying the response until a predetermined displacement has occurred between occupant and vehicle. Peak accelerations and total displacements of the occupant as a function of slack are given. The substitution of actual deceleration-time patterns from barrier impacts by simpler functions of similar shape shows that average deceleration rather than single peaks of short duration in the input function govern the response of the restrained occupant.

The value of the restraint by legs and arms of a human being has been generally disregarded in the development of restraint systems for occupants of an automobile. As part of a series of tests on human beings in automotive restraints conducted for the National Bureau of Standards by the 6571st Aeromedical Research Laboratory, Holloman Air Force Base, New Mexico, measurements were made of the forces exerted on a foot rest during 15 g decelerations. Calculations revealed that for "lap belt only" configuration, 26% of the subject's kinetic energy absorbed was attributed to the seat belt and 55% attributed to the restraint by the legs.

An acceleration sled carrying living human subjects was used to measure the dynamic response of the head and neck to —G x impact acceleration. Seated volunteers with complete pelvic and upper torso restraint were subjected to increasing impact accelerations beginning at 2.7 g and increasing in 1 g increments. The volunteers were selected to encompass the 5th to 95th percentile distribution of sitting height according to a selected reference. Precision inertial transducers were used to determine the linear and angular acceleration of the head and the first thoracic vertebra. The inertial system consisted of a biaxial accelerometer and rate gyroscope on a bite-plate, a biaxial acceierometer over the bregma, and a biaxial acceierometer and rate gyroscope over the spinous process of the first thoracic vertebra. The transducers on the bite-plate and over the bregma were rigidly connected to one another.

Frictional and engine cleanliness properties of 2-cycle engine oils are apparently related. This tentative conclusion is reached after comparing results from a friction rig with those measured in various water- and air-cooled engines. Early results also show that: bright stock improves the frictional properties and engine performance of 2-cycle engine oils; additives which impart dynamic stick- slip (chatter) to an oil perform poorly in high performance engines; and insufficient data are available to determine the merits of ash and ashless type detergents.

The paper describes areas of unsatisfactory performance of most commercial outboard oils being marketed today. It describes the short-term testing techniques used to evaluate lubricating oils at Outboard Marine Engineering. These techniques evaluate oil performance with respect to deposits in the combustion chamber and on the piston skirts, piston ring sticking, lubrication ability, spark plug life, and preignition tendencies. Long-term testing techniques are also described. Finally, an ashless oil using an amide type additive with outstanding performance is described and its performance characteristics are shown.

Field tests were conducted in a variety of Japanese two-cycle gasoline engines, comparing several lubricating oil additive types in motorcycle and small truck service. Three popular types of two-cycle additives were tested, the non-metallic amide and imide types, and the metallic sulfonate type. These field studies showed that (1) at moderate-to-high additive treatments, the amide type gave superior performance followed by the imide type, and then the sulfonate type; (2) at lower additive treatment, the imide type gave superior performance, followed by the sulfonate type, and then the amide type.

As part of a program of fundamental studies of combustion in engines a range of experimental test procedures has been developed which permits numerous aspects of fuel performance to be studied in engines of different designs. This has made it possible to identify regions of engine operation where the performance is below the design requirements, and in some cases to discover unsuspected faults in the operation of the units. This paper presents an account of a systematic approach developed for this type of work together with the experimental techniques used.

Cycle-to-cycle variation of pressure is a common problem in all spark-ignition engines. To examine the suspected influence of mixture-motion on this variation, a study was performed in a constant volume cylindrical bomb in which a jet of propane-air mixture was directed at the initial flame kernel. The rate of pressure rise of the jet-influenced combustion was compared to the rate for combustion in a quiescent mixture. The flame area, obtained using a spark schlieren photographic technique, and the calculated combustion rate were correlated with the pressure rate. The major results were: the rate of pressure rise increased approximately linearly with mixture jet velocity; and the width of the mixture-jet had an effect on the rate of pressure rise. A jet profile width slightly greather than the spark-gap produced the highest rate of pressure rise.

The combustion processes in a compression-ignition engine of the direct-injection type are examined by the independent variation of the partial pressure of oxygen in the intake charge coupled with analyses of rates of heat release employing computer methods.

Dual fuel engines compress the air/gas fuel mixture to just below autoignition conditions and then ignite it by the injection of a small amount of liquid fuel. The use and performance of these engines, however, have been limited by knock. Single cylinder engine experiments show that this limitation is a readily defined autoignition phenomenon, and can be analyzed by a mathematical model that indicates the effects on performance imposed by fuel changes and operating conditions. Experimental findings confirm that these performance data correlate broadly with those obtained conventionally in standard spark ignited or motored engines.

Differences in the power producing capacities and exhaust emission characteristics of various spark-ignition-engine fuels are frequently obscured by interactions involving the particular engine system used in the comparison. In an attempt to minimize this problem, gasoline, propane, methane, and a hydrogen-methane fuel gas were compared in a single cylinder engine under conditions that were optimum for each fuel. The resulting data, coupled with an estimated duty cycle representative of traffic service, permitted the development of internally comparable data on fuel consumption and exhaust emissions. Smog-inducing hydrocarbon emissions from the exhaust of a propane-fueled engine can be less than 13% of the minimum value obtainable with a gasoline fueled engine. Such emissions would be substantially eliminated with a well designed methane engine.

Cycle-to-cycle variations of the combustion process of spark ignition engines, usually observed as peak pressure variations, are a phenomenon whose causes have not yet been identified with certainty. For investigating whether or not there is a relationship between physical cycle characteristics, such as peak pressure, and exhaust gas composition, a sampling system was developed which collects bag samples from specified cycles only. It consists of an analog portion for obtaining pressure and rate-of-pressure change signals, a digital logic portion for discriminating between signals according to selected criteria, and an electrically actuated sampling valve in the engine exhaust system. Since signal analysis and discrimination are instantaneous, gas sampling is done during the exhaust stroke of the same cycle for which the logic generated the command to sample. The system is described in detail and its use is illustrated with an example.

Forty-six automobile collisions with 82 child occupants have been studied. Emphasis was placed on the mechanism of injury production and child collision kinematics. A number of case examples illustrate these injury patterns. Also included are example cases of the effects of collisions in pregnancy and cases of restrained children. Childhood growth characteristics as they affect injury patterns and restraint systems are discussed in detail. An analysis of current types of restraint systems is included and recommendations are made. Collision and comfort-convenience requirements of an “ideal” restraint system are listed.

The objective of this study is to determine whether gross passenger car characteristics are associated with the frequency of vehicle rollover. The characteristics examined are vehicle weight, track width, and vehicle height. Data used in the study are drawn from two states participating in the ACIR program and represent all accidents, property damage as well as injury, investigated by the state police for a period of one year. Data from each state are examined independently and results are then compared. The data indicate that there is a strong correlation between rollover frequency and vehicle dimensions: rollover increases as car size shifts from heavy, wide track, low vehicles to light, narrow track, high cars. Car weight and tread width appear to have the greatest influence on vehicle overturn.

Scientific methodology and engineering techniques were applied to a series of three automobile rear-end collision experiments to provide data relating to seat, seat backrest, and head-restraint design. Five seat back heights and four seat back strength values were studied in connection with their practicality and relative protective features, when subjected to a 55 mph rear-end collision exposure. These research data provide a basic reference system of high-speed collision performance for seat designs with respect to occupant size and proximity to injury producing structures. Additionally, methodology, instrumentation, and related equipment required for post-crash fire studies were included in experiment 106, providing what is believed to be the first published data on the precise time-related events associated with collision-induced passenger car fires. Design revisions suggested by these findings are discussed.

Experimental crash data are examined to determine how vehicle rigidity influences seat belt operation. Total occupant braking distance is maximized when a vehicle has high frontal deformation, as belt loading occurs at impact. However, for any given vehicle optimum conditions occur when: 1. Dead time between impact and belt loading is minimized. 2. Seat belt webbing characteristics are matched to vehicle structure to use maximum available braking distance.

This paper is a discussion of some of the more important considerations and parameters involved in child restraint system design. The success of an effective system for preventing child injury must be measured in terms of child contentment and user convenience as well as impact performance and anatomical considerations. It is the objective of this paper to stimulate the designer of child restraint systems into a realistic reappraisal of the relative importance of the four fundamental ingredients of a successful child restraint system: impact performance, child contentment, convenience, and market appeal.