While the exact number is uncertain due to Model S breaking the testing machine, what this means is that at least four additional fully loaded Model S vehicles could be placed on top of an owner's car without the roof caving in.

It may be worth noting that US vehicle safety tests aren't that stringent and most European cars, which might blitz the test just like the Tesla did, are unavailable in the US.

It may be worth noting that US vehicle safety tests aren't that stringent and most European cars, which might blitz the test just like the Tesla did, are unavailable in the US.

Good for them I guess.
I wonder if the car is equally safe for persons hit by it.

U.S. testing, on the other hand, is often deemed somewhat behind the times. Both Euro NCAP and Australia's ANCAP testing procedures have done away with the full-width frontal impact test in favor of the offset frontal impact. Both have also added a 'pole test', which impacts the car from the side with a steel pole. In Australia, the bonus points scored by cars that fare will in this test are necessary to score five stars. A failure results in a maximum possible of four stars.

The NHTSA requires neither a unique test nor ESC, relying only on the crash data itself to justify its star ratings. For a five-star NHTSA rating, the occupants must be exposed to a 10% or less chance of serious bodily injury. Unlike the NHTSA, the IIHS performs offset impact testing, and the NHTSA recommends drivers compare both ratings to get a feel for the overall safety picture of their vehicle.