[slaxman]

You want the front of the car to absrob the energy. When it crumples, it absorbs the energry and lesser energy is transferred to the passengers. The Engine is tough and will not crumple. It will thus not absorb the energy but transfer it to the passengers.

[ssmoot]

So I just checked out some crash videos on YouTube. The Model S appears to have a surprisingly small crumple zone.

That's just my layman's perspective, but take a look and see if you don't agree. The front readily collapses, but just past the center-point of the wheels (presumably about where the motor area starts) it's a brick wall and the whole 2+ ton vehicle just stops in it's tracks.

Compare that to Volvo crash tests, especially the Euro NCAP Small Offset. The front fender of the Volvo disintegrates, but then the wheel actually flys off and the front of the cabin even appears to absorb some energy. It looks like a much softer landing. The interior shots are even more impressive with less deformation and a lot more padding with a lot less slack in the airbags.

Taking a look at the XC90, it's probably no surprise then that it achieves significantly higher ratings, despite having a 4-cylinder ICE in the engine bay. (see http://www.euroncap.com/en/results/volvo/xc90/20976 and http://www.euroncap.com/en/results/tesla/model-s/7897)

I didn't run across any Model S tests where it looked like that long hood was actually doing much for it since it appears to hit some sort of impenetrably stiff wall halfway through. You can look at the crash test video during a Musk demonstration and see the same thing. There's some sort of structural member there in front of the motor that just doesn't seem to give way.

BTW, it actually appears the Honda Accord mentioned is slightly safer (except for pedestrians) despite the tested model being 5 years older.

The Model S is no doubt a very safe vehicle overall. But it's not the second coming, and Musk's talk of crumple zones appears to be more Marketing than Truth (and the ratings bear that out).

That "Tesla Model S breaks roof test" for example? Not the strongest. Not even at the time of testing. Here's the current generation XC90's results for example: http://www.iihs.org/iihs/ratings/vehicle/v/volvo/xc90-4-door.... Over 10 tons. The previous generation was off about a ton. As far as I can figure out both figures are greater than the Model S's despite the fan-faire.

[creshal]

And as I already mentioned before, this is simply not true, you can make engines that crumple extremely well.

[robbiemitchell]

It might be possible, but is it common? Is a Honda Accord going to crumple politely?

[CompelTechnic]

Could you provide some evidence/ examples?

[creshal]

https://youtu.be/mnI-LiKCtuE?t=265

Seems I remembered it the wrong way round – it was the Corsa that held up and crumpled well enough to not have significant intrusion even at 110 km/h (70 mph).

[jads]

This isn't really evidence that it's possible to make an engine that can crumple. In fact, quite the opposite.

This particular Corsa B (93-2000) was a 1.4i (1.4L engine) - the physical dimensions of the engine are extremely small[1], and there is a lot of empty space in the engine bay that isn't taken up by the main engine block (excluding various plastics, wiring, etc - actual metal). I don't think it's so much the case that this engine "could crumple", rather that there was a lot of space for the front to crumple into, before there was none left and the engine was then pushed into the cabin.

Engine blocks are, well, blocks of metal. They're not going to crumple in any meaningful way.

[1]: http://iheartautos.co.za/wp-content/uploads/2015/09/engine-b...

[_ea1k]

There was no engine in the front of that car.

[varjag]

This is untrue. ICEs are designed to be dimensionally stable and withstand a lot of mechanical stress due to operation.