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This paper presents the methodology and results of an analysis of the available information on motor vehicle safety which could be used to provide a basis for establishing priorities for future Government and private sector efforts directed at enhanced crash protection. The work was stimulated by several factors: (1) 5 years have elapsed since the National Highway Traffic Safety Administration (NHTSA) published a plan for motor vehicle safety research and development, (2) motor vehicles have changed substantially over the past several years, (3) the quantity and quality of accident data and vehicle crash performance information have increased dramatically over the past 5 years, and (4) Government policies and the amount of Government and private sector resources available for future efforts are changing.

The subject is treated on the basis of detailed engineering test data regarding components and parameters of 1975 autos. The applicability of the simulation approach is examined by extensive comparisons with integrated vehicle test results. It is found that fuel economy, for the EPA driving schedules, is adequately simulated with 5% to 10% uncertainties. Uncertainties of the same magnitude are also encountered in performance simulations. Larger uncertainties are evident in the simulation of emissions. NOx prediction has an uncertainty up to 25% but no significant bias, while CO and HC are very substantially over-predicted and under-predicted respectively. Excepting HC and CO, several applications are made in the evaluation of sensitivities to various auto components and parameters. Evaluations are made of changes in auto weight, engine displacement and rear axle ratio, considered individually and in combinations.

The subject is treated by statistical and engineering analyses applied to extensive measurements of fuel economy and acceleration performance. Fuel economy data are provided by the EPA certification lists for the four years 1973 to 1976. The performance data are track measurements of 0 to 60 MPH acceleration times for 1974 and 1975 vehicles, as reported in the popular automotive literature. Several relations, supported by engineering analyses, are selected for making least-squares fits to the extensive measurements. The pivotal variables include: inertia weight, horsepower, engine displacement and rear axle ratio, individually and in combinations. Satisfactory fits are made by power factorial forms and the resulting algorithms have standard errors of estimate in the vicinity of 10% for fuel economy and in the range 10% to 15% for acceleration time.

This paper addresses the crash protection of occupants of the car fleet in transition from the late 1970's to the early 1980's. Three files of the National Highway Traffic Safety Administration are used: the NASS 1979 to 1983, the PARS 1979 to 1983, and the NCSS 1977 to 1979. Fatalities, injured survivors by severity, and all accident involved car occupants are addressed. Risks of crash and injury outcomes are determined and analyzed as a function of risk influencing factors, especially factors that may vary significantly during the time period under consideration. Ejection risks and ejection patterns are addressed explicitly. Harm, an earlier introduced human casualty integrator, and harm distributions are extensively examined and updated with respect to earlier results. Harm and harm pattern changes, whether statistical fluctuations or systematic variations, are analyzed.

This paper addresses the risks of occupant casualties in highway accidents. Such risks are determined from U.S. accident experience in the past 10 years. Risks are analyzed as a function of vehicle type, car market class, make, nameplate, and model year for crashes of various impact types and various severities. Both absolute risks, per unit exposure, and relative risks are addressed. The influence of many exposure variables is examined and necessary adjustments, to a common set of exposure conditions, are made. The control variables for this purpose are: calendar year and car age; occupant's seating position, restraint status, and age; time and place of travel; and various roadway characteristics. Adjusted risks are reviewed versus major characteristics of cars as implied by make, nameplate, and model year. Occupant ejections and rollovers receive special attention due to their risk sensitivity to car class