Trends in the Static Stability Factor of Passenger Cars, Light Trucks, and Vans

Rollover crashes kill more than 10,000 occupants of passenger vehicles each year. As part of its mission to reduce fatalities and injuries, since model year 2001, the National Highway Traffic Safety Administration (NHTSA) has included rollover information as part of its New Car Assessment Program (NCAP) ratings. One of the primary means of assessing rollover risk is the static stability factor (SSF), a measurement of a vehicle's resistance to rollover. The higher the SSF, the lower the rollover risk. This report tracks the trend in SSF over time, looking in particular at changes in various passenger vehicle types. Data are presented for overall fleet average SSFs by vehicle type over a number of model years. Passenger cars, as a group, have the highest average SSF, and these have remained high. Sport utility vehicles (SUVs) have substantially improved their SSF values over time, especially after model year 2000, whereas those of pickup trucks have remained consistent over the years. Minivans showed considerable improvement since they were first introduced, while full-size vans showed a small but steady improvement. In model year 2003, the sales-weighted average SSF was 1.41 for passenger cars, 1.17 for SUVs, 1.18 for pickup trucks, 1.24 for minivans, and 1.12 for full-size vans.


  • English

Media Info

  • Media Type: Print
  • Edition: Technical Report
  • Features: Appendices; Figures; Tables;
  • Pagination: 39p

Subject/Index Terms

Filing Info

  • Accession Number: 01008880
  • Record Type: Publication
  • Source Agency: National Highway Traffic Safety Administration
  • Report/Paper Numbers: HS-809 868
  • Files: HSL, TRIS, USDOT
  • Created Date: Nov 16 2005 3:44PM