In the small overlap front crash test, the Tesla's safety belt didn't prevent the dummy's head from hitting the steering wheel through the airbag. The IIHS also noted a possible leg injury in that test. Tesla said it would fix this issue in cars produced beginning January 26, so now its IIHS' turn to smash the car up again to see if its rating improves.
Interestingly, the P100D variant only earns an "acceptable" rating in the rollover test. The roof strength is no different from the rest of the Model S lineup, which are rated "good," but the weight of its big battery puts more stress on the structure while shiny-side-down. Finally, its headlights get a "poor" rating from the IIHS.
The BMW i3's biggest shortcoming is in its head restraints. In a rear-end collision, it only gets an "acceptable" rating, which puts occupants at a greater risk of a neck injury. The IIHS laments that the i3 is the only vehicle in the small car category that doesn't get a "good" rating in this test. The i3's headlights also miss the mark, as the only option gets an "acceptable" rating.
"There's no reason that the most efficient vehicles can't be among the safest," says David Zuby, IIHS chief research officer. If you're wondering about the Chevrolet Bolt, the IIHS says it'll obliterate examples of it in the name of safety later this year.