Model 3 Crash Safety

[mongo]

But Model 3 is better in single-car crash because it is designed with the latest crash tests/standard in mind, especially the 25% small overlap frontal crash test.

In regards to this, it looks like the 3 battery pack is tapered at the corners (possibly with its own crumple zone) which may help with deflecting the vehicle in the offset test v.s. a hard stop on the flat surface of the S/X pack .

 

[dm33]

I guess the likeliness of an event occurring where the rear passengers need to quickly escape is pretty low, and adults and children could just crawl to the front seats, or parent could reach back to help smaller children.

Why would the likelihood of needing to quickly escape from the rear seat be any lower than needing to escape from the front seat?
Would it be reasonable to make a car that you can't get out of if you're in an accident and can't open the front doors?
Is the need to get out of a car after an accident somehow unlikely?

And smaller children aren't the only people who seat in the back of the car. I plan to have teenagers bigger than me, other adults, even grandparents regularly sitting in the rear seat.

 

[run-the-joules]

Why would the likelihood of needing to quickly escape from the rear seat be any lower than needing to escape from the front seat?
Would it be reasonable to make a car that you can't get out of if you're in an accident and can't open the front doors?
Is the need to get out of a car after an accident somehow unlikely?

And smaller children aren't the only people who seat in the back of the car. I plan to have teenagers bigger than me, other adults, even grandparents regularly sitting in the rear seat.

If there's a mechanical override, the child safety locks are essential devoid of utility. Bet your booty that's why there are no escape levers. In an emergency, you just treat it like a very spacious coupe.

 

[dm33]

If there's a mechanical override, the child safety locks are essential devoid of utility. Bet your booty that's why there are no escape levers. In an emergency, you just treat it like a very spacious coupe.

Child safety locks are an option not always enabled. I have never owned a car where I've enabled them nor have I ever been in the back seat of a car with child locks enabled.

Would you be comfortable in the front seat of a car if you couldn't open the doors in case of an accident because power was out?

Child safety locks are a mechanical option. Every other car has a mechanical way to open the back doors if child safety locks aren't engaged.

 

[run-the-joules]

Child safety locks are an option not always enabled. I have never owned a car where I've enabled them nor have I ever been in the back seat of a car with child locks enabled.

Would you be comfortable in the front seat of a car if you couldn't open the doors in case of an accident because power was out?

Child safety locks are a mechanical option. Every other car has a mechanical way to open the back doors if child safety locks aren't engaged.

Welcome to the brave new world, I suppose. I think this is some pretty intense edge-case focus that doesn't really concern me, but if people feel that strongly the smartest play is to vote with their wallets and try and rustle up some media coverage as well.

 

[Az_Rael]

It is very easy to have enough damage to your doors after an accident that they won't open anyways even with a mechanical release. In my recent accident, my front door was damaged enough that I had to muscle it open past the bent aluminum. If the fellow had hit a few inches farther forward, I wasn't getting out that door mechanical release or not.

Also, my seatbelt had snugged up and I was pinned to my seat after the accident. Luckily, it still unbuckled, but consider the scenario where the buckle had been damaged and wouldn't release.

Everyone should keep one of those seatbelt cutter/window breakers handy and reachable while you are buckled in snug to a seat. Keep one in the backseat too for the backseat passengers.

 

[stopcrazypp]

Child safety locks are an option not always enabled. I have never owned a car where I've enabled them nor have I ever been in the back seat of a car with child locks enabled.

Would you be comfortable in the front seat of a car if you couldn't open the doors in case of an accident because power was out?

Child safety locks are a mechanical option. Every other car has a mechanical way to open the back doors if child safety locks aren't engaged.

The difference with front doors is that those may be the only exit option in the car (for example coupes).

But let's consider the circumstances where this even comes into play. It is the case where the crash is severe enough to disable the power, but not severe enough to deform or damage the rear doors such that you can't open it anyways. Another factor is that if it is like the Model S (where doors auto unlock on airbag deployment), that might narrow things further.

 

[T-Will]

Why would the likelihood of needing to quickly escape from the rear seat be any lower than needing to escape from the front seat?
Would it be reasonable to make a car that you can't get out of if you're in an accident and can't open the front doors?
Is the need to get out of a car after an accident somehow unlikely?

And smaller children aren't the only people who seat in the back of the car. I plan to have teenagers bigger than me, other adults, even grandparents regularly sitting in the rear seat.

Good questions, all I was saying is the scenario we’re discussing is an edge case (where the electronic latches have become disabled by the impact).

 

[scaesare]

Wise words : Judge me by my size you should not.

That video is indeed a testament to the design that went in to the passenger cage of the Smart Car. Passenger space intrusion is only half the story however. The other half is g-force load due to deceleration.

There are typically two factors associated with deceleration: distance and time of the event. Because of the size of the Smart Car, there is a very small frontal zone distance to decelerate over. Hence, for a given speed the g-forces the occupants experience will be higher than a car with a longer crumple zone.

The lesser mass of the Smart Car also means it will decelerate more quickly than the opposing car of equal mass. You can clearly see this in the video.. the Smart Car has decelerated completely, and actually begins to reverse direction while the more massive car is still decelerating.

While it's stated for the video that the forces were below the survivability threshold for that test, physics dictate that the Smart occupants experienced higher loads than the other car. And that was a 50km/h test (~31 MPH). At some point higher in the speed scale there will be a point where the Smart's occupant's will experience lethal G-forces and the other car's occupants likely would not have.

So in some aspects, you DO have to judge by size.

As this relates to model 3... there's some probability that in a similar head on test, the 3 will have greater G-force loads as compared to an opposing S. However I think the correct comparison is to ICE sedans in similar size/class. I expect it will perform much better than the equivalent BMW 3 or Audi 4 series.

 

[EV-lutioin]

I know that Elon said that one the presentation in 2016 but later they write that they had the goal to get 5 star rating, have they confirmed that they will get 5 star in every category?

Here is what he said at the Model 3 reveal; “There are a lot of cars that say they are 5-star … there is not a scientific metric,” Musk wryly pointed out. “The Volvo [S60] is arguably the second safest car in the world.”

reveal: “There are a lot

 

[maxell2hd]

Here is what he said at the Model 3 reveal; “There are a lot of cars that say they are 5-star … there is not a scientific metric,” Musk wryly pointed out. “The Volvo [S60] is arguably the second safest car in the world.”View attachment 273471 reveal: “There are a lot

That video can be misleading. The Model S is similarly rigid (see 66s mark of video) but in NHTSA's quantitative evaluation, the S60 scores much better.

 

[SmartElectric]

While it's stated for the video that the forces were below the survivability threshold for that test, physics dictate that the Smart occupants experienced higher loads than the other car. And that was a 50km/h test (~31 MPH). At some point higher in the speed scale there will be a point where the Smart's occupant's will experience lethal G-forces and the other car's occupants likely would not have.

Indeed. The Smart design as a city car where speed limits of 60 km/h are enforced makes sense for the size and speed scale. I've driven 30000 km with an average speed of 30 km/h over the past 4 years on my daily commute, and the Smart meets that need.

As for the Model 3, I was highlighting that car size/scale/mass is not the only way to judge safety, nor is it even the most important element.

I dislike the "wrap your kids in a massive SUV cocoon" mantra for safety. While this seems ironic for someone like me who owns a massive Model S, we didn't buy the Model S for the school run, we do that in the Smart. The S is for highway travel, and that is the majority of the use ours gets.

 

[scaesare]

Indeed. The Smart design as a city car where speed limits of 60 km/h are enforced makes sense for the size and speed scale. I've driven 30000 km with an average speed of 30 km/h over the past 4 years on my daily commute, and the Smart meets that need.

As for the Model 3, I was highlighting that car size/scale/mass is not the only way to judge safety, nor is it even the most important element.

I dislike the "wrap your kids in a massive SUV cocoon" mantra for safety. While this seems ironic for someone like me who owns a massive Model S, we didn't buy the Model S for the school run, we do that in the Smart. The S is for highway travel, and that is the majority of the use ours gets.

However I see them on the highway travelling at >2x those speeds around here.

In the context of this discussion, many people could interpret the relatively terse "Judge me by my size you should not." words as implying size doesn't matter. It does. And in some cases that size (not necessarily mass) is the most important differentiator. Hence my comment.

 

[Doug_G]

Surely the 3 has a 12V system, like all other Teslas. Just because the main pack goes offline in a crash doesn’t mean the doors won’t work.

 

[anticitizen13.7]

Surely the 3 has a 12V system, like all other Teslas. Just because the main pack goes offline in a crash doesn’t mean the doors won’t work.

This is correct.

https://www.tesla.com/sites/default/files/downloads/2017_Model_3_Emergency_Response_Guide_en.pdf

On p.10:

In addition to the high voltage system, Model 3 has a low voltage electrical system. Its 12 volt battery operates the SRS, airbags, windows, door locks, touchscreen, and interior and exterior lights. The high voltage system charges the 12 volt battery, and the 12 volt battery supplies power to the high voltage contactors, allowing high voltage current to flow into and out of the high voltage battery. The 12 volt battery, outlined in red, is located under the hood and the plastic access panel

During an investor conference call, Elon had indicated that Tesla intended to move away from 12V lead acid batteries at some point.

I would not expect this to happen until Model Y or a product generation beyond.

 

[vigge50]

Here is what he said at the Model 3 reveal; “There are a lot of cars that say they are 5-star … there is not a scientific metric,” Musk wryly pointed out. “The Volvo [S60] is arguably the second safest car in the world.”View attachment 273471 reveal: “There are a lot

That's funny, then IIHS tested Model S and found out that the seat belt didn't work so well then 5 star was the only thing that matter...