The Model S, a large luxury sedan, earns good ratings in all IIHS crashworthiness evaluations except the challenging small overlap front crash test, in which it earns an acceptable rating. Despite lengthening the side curtain airbags to improve small overlap protection in the Model S, Tesla ran into problems in the test when the safety belt allowed the dummy’s torso to move too far forward. That allowed the dummy’s head to hit the steering wheel hard through the airbag. Measurements from the dummy indicated that injuries to the head, along with the lower right leg, would be possible in a real-world crash of the same severity.
The ratings for the Model S apply to 2016 and 2017 cars built after October 2016. Tesla says it made a production change on Jan. 23 to address the head-contact problem, and IIHS will test the updated vehicle for small overlap protection as soon as it can be delivered.
Although the i3, the Volt and the Prius all did better in the small overlap evaluation than the Model S, the results can’t be compared because the Model S is larger than the others. Since the kinetic energy involved in a front crash depends on the speed and weight of the vehicle, the Tesla’s acceptable rating is based on a more severe crash than the good ratings of the lighter cars.
One version of the Model S, the P100D, also falls short on roof strength, which is important for protecting people in a rollover crash. The rating is based on a strength-to-weight ratio. The P100D has the same roof structure as other Model S versions, but the car is heavier, due to a larger battery, so it earns only an acceptable rating.
Discover new cars with Test Drive channel: http://bit.ly/1ikP6w1