Aren there already rollover ratings on NHTSAs website?
Yes, but we believe the measure NHTSA is using provides too coarse a measure of vehicle stability. Currently NHTSA provides rollover ratings on its website (http://www.nhtsa.dot.gov/cars/problems/Rollover/vehicle_ratings.htm) that are based on a vehicle’s “Static Stability Factor,” or SSF. SSF has been used as one method of evaluating rollover propensity. It is a calculation based on two aspects of the vehicle: center of gravity, height, and track width (T/2H, with H being the center of gravity height and T being the track width). CU believes risk estimates based on SSF alone – and what appears currently as ratings on NHTSA’s website – is too coarse a measurement to give an accurate picture of a vehicle’s propensity to roll over. We favor adding the results of a dynamic rollover test program to the SSF score, along with ratings from dynamic emergency handling tests, because these treat the vehicle as a unit, measuring its performance as a whole. Such an approach includes many more vari
