U.S. Department Transportation National Highway Traffic Safety Administration DOT HS 808 679 Final Report DOT-VNTSC-NHTSA-98-1 February 1998 Vehicle Aggressivity: Fleet Characterization Using Traffic Collision Data Hans Joksch Dawn Massie Robert Pichler The University of Michigan Transportation Research Institute 2901 Baxter Road Ann Arbor, MI 48109-2150 This document is available to the public through the National Technical Information Service, Springfield, VA 22161 NOTICE This document is disseminated under the sponsorship of the Department of Transportation in the interest of information exchange. The United States Government assumes no liability for its contents or the use thereof. NOTICE The United States Government does not endorse products or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered essential to the objective of this report. Form Approved REPORT DOCUMENTATION PAGE OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704- 0188), Washington, DC 20503. 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 3. REPORT TYPE AND DATES COVERED PB98-118094 February 1998 Final Report (Sep. 1995 – Sep. 1997) 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Vehicle Aggressivity: Fleet Characterization Using Traffic Collision Data S8010/HS876 6. AUTHOR(S) Hans C. Joksch, Dawn Massie, and Robert Pichler 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION The University of Michigan* REPORT NUMBER Transportation Research Institute 2901 Baxter Road Ann Arbor, MI 48109-2150 DOT-VNTSC-NHTSA-98-1 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING/MONITORING U.S. Department of Transportation AGENCY REPORT NUMBER National Highway Traffic Safety Administration Safety Systems Engineering and Analysis Division 400 7th Street, S.W. DOT HS 808 679 Washington, DC 20590 11. SUPPLEMENTARY NOTES *Under contract to: U.S. Department of Transportation Research and Special Programs Administration John A. Volpe National Transportation Systems Center Cambridge, MA 02142-1093 12a. DISTRIBUTION/AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE This document is available to the public through the National Technical Information Service, Springfield, VA 22161 13. ABSTRACT (Maximum 200 words) Aggressivity of a vehicle is defined as the fatality or injury risk for occupants of other vehicles with which it collides. Because of the strong effect vehicle weight has on this risk, gross aggressivity which includes the effect of weight, and net aggressivity which excludes the effect of weight are distinguished. Data from the Fatal Analysis Reporting System (FARS) and the General Estimates System (GES) for 1991 to 1994 were used for fatalities, and for crash involvements, respectively. The relation between weight and wheelbase of cars was studied, and the concept of “overweight” introduced. For collisions between two cars, the relation of fatality risks with car weight, overweight, wheelbase and bumper height were studied. Also, adjustments were made for the higher vulnerability of older victims. Collisions between cars and light trucks – including utility vehicles, pickup trucks and vans – were studied. A limited analysis of the effect of vehicle weight was performed. The driver fatality risks in collisions between cars and light trucks were studied by collision configuration. In all cases, the risk for car drivers was much higher than for drivers of light trucks. 14. SUBJECT TERMS 15. NUMBER OF PAGES fatalities, injury risk, cars, trucks, vans, vehicle weight, wheelbase 82 16. PRICE CODE Paper: A06; Fiche: A02 17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION 19. SECURITY CLASSIFICATION 20. LIMITATION OF ABSTRACT OF REPORT OF THIS PAGE OF ABSTRACT N/A Unclassified Unclassified Unclassified NSN 7540-01-280-5500 Standard Form 298 (Rev. 2-89) Prescribed by ANSI Std. 239-18 298-102 iii METRIC/ENGLISH CONVERSION FACTORS ENGLISH TO METRIC METRIC TO ENGLISH LENGTH (APPROXIMATE) LENGTH (APPROXIMATE) 1 inch (in) = 2.5 centimeters (cm) 1 millimeter (mm) = 0.04 inch (in) 1 foot (ft) = 30 centimeters (cm) 1 centimeter (cm) = 0.4 inch (in) 1 yard (yd) = 0.9 meter (m) 1 meter (m) = 3.3 feet (ft) 1 mile (mi) = 1.6 kilometers (km) 1 meter (m) = 1.1 yards (yd) 1 kilometer (km) = 0.6 mile (mi) AREA (APPROXIMATE) AREA (APPROXIMATE) 1 square inch (sq in, in2) = 6.5 square centimeters (cm2) 1 square centimeter (cm2) = 0.16 square inch (sq in, in2) 1 square foot (sq ft, ft2) = 0.09 square meter (m2) 1 square meter (m2) = 1.2 square yards (sq yd, yd2) 1 square yard (sq yd, yd2) = 0.8 square meter (m2) 1 square kilometer (km2) = 0.4 square mile (sq mi, mi2) 1 square mile (sq mi, mi2) = 2.6 square kilometers (km2) 10,000 square meters (m2) = 1 hectare (ha) = 2.5 acres 1 acre = 0.4 hectare (ha) = 4,000 square meters (m2) MASS - WEIGHT (APPROXIMATE) MASS - WEIGHT (APPROXIMATE) 1 ounce (oz) = 28 grams (gm) 1 gram (gm) = 0.036 ounce (oz) 1 pound (lb) = .45 kilogram (kg) 1 kilogram (kg) = 2.2 pounds (lb) 1 short ton = 2,000 pounds (lb) = 0.9 tonne (t) 1 tonne (t) = 1,000 kilograms (kg) = 1.1 short tons VOLUME (APPROXIMATE) VOLUME (APPROXIMATE) 1 teaspoon (tsp) = 5 milliliters (ml) 1 milliliter (ml) = 0.03 fluid ounce (fl oz) 1 tablespoon (tbsp) = 15 milliliters (ml) 1 liter (l) = 2.1 pints (pt) 1 fluid ounce (fl oz) = 30 milliliters (ml) 1 liter (l) = 1.06 quarts (qt) 1 cup (c) = 0.24 liter (l) 1 liter (l) = 0.26 gallon (gal) 1 pint (pt) = 0.47 liter (l) 1 cubic meter (m3) = 36 cubic feet (cu ft, ft3) 1 quart (qt) = 0.96 liter (l) 1 cubic meter (m3) = 1.3 cubic yards (cu yd, yd3) 1 gallon (gal) = 3.8 liters (l) 1 cubic foot (cu ft, ft3) = 0.03 cubic meter (m3) 1 cubic yard (cu yd, yd3) = 0.76 cubic meter (m3) TEMPERATURE (EXACT) TEMPERATURE (EXACT) °C=5/9(°F - 32) °F=9/5(°C) + 32 QUICK INCH-CENTIMETER LENGTH CONVERSION INCHES 0 1 2 3 4 5 CENTIMETERS 0 1 2 3 4 5 6 7 8 9 10 11 12 13 QUICK FAHRENHEIT-CELSIUS TEMPERATURE CONVERSION °F -40° -22° -4° 14° 32° 50° 68° 86° 104° 122° 140° 158° 176° 194° 212° °C -40° -30° -20° -10° 0° 10° 20° 30° 40° 50° 60° 70° 80° 90° 100° For more exact and or other conversion factors, see NIST Miscellaneous Publication 286, Units of Weights and Measures. Price $2.50. SD Catalog No. C13 10286. Updated 8/1/96 iv 24'(#%' This report contains the results of a study to evaluate the crashworthiness and aggressivity of cars and light trucks. Data from the Fatal Analysis Reporting System (FARS) and the General Estimates System (GES) for 1991 to 1994 were used for fatalities and for crash involvements, respectively. This work was performed by the University of Michigan Transportation Research Institute under contract to the Volpe National Transportation Systems Center in support of the National Highway Traffic Safety Administration’s program on Vehicle Aggressivity and Fleet Compatibility. v vi 6#$.'1(%106'065 Section Page Executive Summary ES-1 1. Introduction....................................................................................................... 1 2. Databases .......................................................................................................... 3 3. The concept of aggressivity............................................................................... 7 4. Confounding factors.......................................................................................... 9 5. Vehicle weight and size..................................................................................... 11 5.1 The effect of vehicle weight ....................................................................... 11 5.2 Vehicle size................................................................................................ 14 5.3 The relation between car weight and wheelbase......................................... 15 5.4 Risk to car occupants in collisions with cars.............................................. 17 5.5 Risk to car occupants in single-car collisions and rollover......................... 22 6. Classifying cars ................................................................................................. 26 6.1 Purpose of classifying cars ......................................................................... 26 6.2 Attempts at statistical classifications.......................................................... 27 6.3 Developing car families.............................................................................. 28 7. Comparing families of cars ............................................................................... 30 7.1 Risks by family........................................................................................... 30 7.2 Relations between different types of risks.................................................. 40 7.3 Relating risks to weight and wheelbase...................................................... 43 7.4 Aggressivity and bumper height................................................................