Glass roof rollover safety?

Glass roof rollover safety?

I have not seen any comments or conjecture about the potential hazards if an M3 is involved in a rollover event? Granted, the center roof bar will protect the occupants from crushing hazards. However, will the "glass" roof stay in place to prevent heads and limbs from being exposed to sliding pavement, etc.? As an S85D owner, I understand the potential for a rollover is low, but they will inevitably happen. Anyone have factual or reality-based information or ideas?

topher | 9 May 2016

Only anecdotal evidence but this car rolled at least once:

The NHTSA gives the Model S a five star rating, in all categories. As to the roof:
"The car reportedly broke the machine NHTSA uses for roof-crush evaluations."

Thank you kindly. | 9 May 2016

Beyond topher's excellent answer, whether the roof is glass or metal (on any car) it has the potential in some rare kinds of accidents to be ripped off. It's the structure around it that is the most important. If the roof crushes in a rollover (as it will in most cars), game over for the occupants. Since most cars are "crushable" I guess you really don't have to worry if the top is ripped off first in those vehicles, as you'll likely be dead anyway.

I'm glad you own a Tesla, being dramatically safer than any other car, and I expect the M3 to be just as safe. I would hope you use your seat belts to avoid further injuries in a severe accident.

Bubba2000 | 9 May 2016

I think Tesla uses a Boron steel safety cage design, including the roof members in the Model S. That car got to be among the safest if not the safest. Tesla will probably use similar design. Regular metal roof without reinforcement is not different than toughened glass. Hard to believe but the 18 yo driver in Germany managed to do a barrel roll of a Model S!

PeterPlt | 10 May 2016

The benefit of seatbelts is unassailable. I walked away from a helicopter crash into tall jungle (shot down) without a scratch due to a great seat system and a four point seat harness. The three point belt system in the Tesla is a good real-world compromise (compared to something like a racing harness). I taught my boys that all seatbelts must be fully engaged prior to shifting the car out of Park. So far, so good.

My original point: I hope Tesla will use a heavier glass/plastic sandwich for the roof than is used in the windshield to further protect occupants in all seats during a rollover.

Hi_Tech | 10 May 2016

I've been amazed with the level of safety of the Model S to date. Lots of stupid driver incidents/news out there and in any case where a Tesla was involved, you can tell that one of the safest places to be in was the cabin.

To PeterPit's point, I also wonder about how structurally sound the "all-glass" roof will be for Model 3. However, I don't doubt that Tesla will manage to make it one of the safest vehicles.

If my son ever does something as stupid as the kid in Germany (above link), I pray to gods that everyone comes out without any injury... but, I doubt the car will be able to save him from the yelling/discipline he'll get from me for being so stupid!

Bubba2000 | 10 May 2016

Tesla could have a "Teenager Mode" that is password protected:
1. Max speed limit and can not exceed posted speed limits
2. Limit geography per GPS, Zip Code, Intestate Highway restrictions
3. Seat belts required with sensors to detect passengers.
4, Camera to record inside and outside
5 Remote control capabilities to disable the car. So even if kid get hold of the key, can not use the car.

Most of this stuff can be done now with software upgrade.

Hi_Tech | 10 May 2016

Something like the valet mode. I like it!

dsvick | 10 May 2016

That'd be awesome!! You forgot one though
6. Automatic check in - the car will send a text/email to the parents on a specified schedule letting them know where it is, how fast it is going, and how many passengers are in it.

jordanrichard | 10 May 2016

You have to realize that a steel roof is nothing more than a sheet of metal. It does nothing in way of providing any crash worthiness. It is the structure that the roof panel is welded to that provides the "safety" aspect to the roof's structure.

weare94 | 10 May 2016

Not sure if this will help but, I was in a rollover accident in a car with a "T-Top" when I was younger. Obviously the glass shattered and the only thing supporting the car was the bar that formed the "T". If I wasn't wearing my seatbelt, I would have fallen to the ceiling and been dragged under the car (sorry to be so graphic). What I'm trying to say is, as long as there is support and you aren't taller than the ceiling, and you're wearing your seatbelt, you should be ok in a rollover, even if all the glass does go away.

PeterPlt | 10 May 2016

@Hi-Tech... Headline: "Kid survives Tesla accident with minor scratches only to be severely bruised by parents!"

@Bubba... How about software that alerts, real time, guardians of exceedances of pre-negotiated parameters (speeds, distances, geography, seatbelt use, no cell or text use in motion, etc.)? There is a million dollar piece of software!

@jordanrichard & weare94 - To complete the point, a metal or shattered but intact "glass" roof will help keep heads and arms from being dragged on asphalt while the car is sliding.

I do agree with the expectation that Tesla will find the best answer practical and is not likely to compromise on safety. That is their culture. | 10 May 2016

So far, Tesla has placed top priority on safety, as evidenced by the performance of the Model S. As long as Elon is in charge the same emphasis will be extended to the design of the M≡.

I like the teen mode. Maybe add periodic electric shocks based on behavior, driving and otherwise.:-))