Mark is pretty much spot on. I have seen some smaller cars do well. I T-Boned a lady in Ft Collins many years ago. I hit her doing 45 smack in the middle of the passenger side front door (there was someone sitting there). Even with the side impact airbags (saved her life) she had a lacerated liver, broken ribs and a punctured lung. She was in a Volvo.
Seat belts are everything, especially in a rollover. The auto accident scene I transported the least number of times was a rollover. Either the occupants were out of the car walking around (they were restrained) or they were out of the car dead (they were not restrained). Very rarely was there an emergent return from a rollover. Think Rusty Wallace (Massive Rollover like 30 times) vs Dale Earnhardt (Straight into the wall)
Every accident is very different as to the mechanism. Speed, location of impact, type of vehicle, all go into how bad an accident is. All in all there are very safe vehicles out there, but even a stupid driver can make the safest vehicle unsafe. Here are a few pics from some accidents I ran on. There were so many more that were even worse, whenever I go back to Omaha I visit the scene of one my worst calls ever, 4 victims, 2 fatalities all high school kids. I was 22 at the time and it was a horrible scene. If you ever take any of my classes just ask, I will tell you about it.
vs. tree (Engine into front seat, this was a fatal)
Range Rover vs. Truck (Loaded with asphalt shingles) He was going very fast and hit this truck going very slow. This was a fatal as well (week later)
