For starters, the company’s roof crush protection was so good it broke the testing machine at an independent commercial facility.
That means, according to Tesla, you could stack four fully-loaded Tesla S vehicles on top of a fifth Tesla and the bottom car’s roof wouldn’t collapse— Tesla says it can’t be sure if that’s the maximum pressure the car can take, seeing as how it broke the testing equipment.
Related to the roof’s rigidity, the car also has a low center of gravity thanks to the battery pan in the Model S.
Other highlights for the Tesla S’s NHTSA performance included driver-side protection that was able to preserve 63.5 percent of the driver’s residual space after impact. Tesla says to protect against side impacts, the Tesla S features multiple deep aluminum extrusions in the car’s side rail that help absorb energy from an impact.