[SEJeff]

This is the part that gets me:

    The Institute’s results also demonstrate the exceptional strength of Model 3’s all-glass roof, which is supported by a very strong metal body structure and helps protect occupants in roll-over crashes. During testing, the car’s roof was able to successfully resist more than 20,000 pounds of force – that’s more than if we placed five Model 3s on top of the car’s roof at once. And, the roof earned a higher strength-to-weight ratio score than any other fully electric vehicle that IIHS has ever tested.

It takes the weight of ~5 Model 3s ontop of a single one for the glass roof to shatter. That's good engineering.

[eatbitseveryday]

Please do not use code formatting for quotes. It creates a terribly long unbroken side-scrollable box.

> The Institute’s results also demonstrate the exceptional strength of Model 3’s all-glass roof, which is supported by a very strong metal body structure and helps protect occupants in roll-over crashes. During testing, the car’s roof was able to successfully resist more than 20,000 pounds of force – that’s more than if we placed five Model 3s on top of the car’s roof at once. And, the roof earned a higher strength-to-weight ratio score than any other fully electric vehicle that IIHS has ever tested.

[SEJeff]

upvoting you for this. I thought it would break it into a block, and was wrong.

[SilasX]

Wow, and seeing how the post appeared after submitting didn't convince you otherwise?

[adt2bt]

What’s with the attitude? He said he was wrong and the child comment fixed the issue. No need to castigate him.

[SilasX]

Just surprised how people are able to miss this.

SEJeff in particular has been a member since 2012 and has 7500 karma, and somehow never saw a post that looked unreadable because of blockquote, including his own.

[skyyler]

I hope your mood improves soon. No one should have to be as bitter as you are right now.

I don't mean this in jest, I really do hope that you find some peace.

[SEJeff]

Well when I looked at it a bit later, I was unable to edit the original comment. Kind of makes the point moot don't you think?

[austhrow743]

This site is absolutely littered with that formatting. It needs to be changed to [yesiampostingcode][/yesiampostingcode] or something like that.

It's not like browsing the internet on a phone is a new concept any more. Little ridiculous how nothing has been done about its frequent use.

[MrBuddyCasino]

Wondering will I ever see the day this gets fixed. Shouldn’t take more than an hour?

[crushingcrash]

This is hilarious to me, how this site is so badly laid out and has so many rendering bugs.

[Sohcahtoa82]

It's not a bug, it's a feature.

Prepending 4 spaces is intended to be used for posting source code, where automatic line wrapping is undesirable.

[MrBuddyCasino]

I mean you could just render it differently on mobile, or at least not with such a tiny bounding box. Its not impossible.

[kazinator]

Note: on HN, just two spaces marks off code.

[gamblor956]

Note: this quote is from Tesla, not the IIHS.

It's marketing speak and isn't supported by anything in the IIHS's actual public announcement on their most recent vehicle safety ratings. Tesla has received flak in the past for misstating the results of IIHS and NHTSA testing.

[helpPeople]

Some people seem more accepting of misinformation than others.

The whole Mars thing + no 30k electric car after all these years have me immune.

Tesla and musk are simply not trustworthy.

[thebluehawk]

Context is important. Pretty much the entire aerospace industry is terrible at time estimates. SpaceX has accomplished some incredible things, so bashing them for "the whole Mars thing" when they are still hard at work on it seems premature and pithy.

And as far as I'm aware they never promised a 30k car? They promised a 35k car, which you can buy today (you just have to email them or go in person and ask for it, it's not available online)

[hndamien]

You appear to be quite accepting of misinformation. Nobody promised a $30k electric car. It was $35k and they delivered it.

[helpPeople]

https://www.caranddriver.com/news/a27120534/tesla-model-3-li...

From this year. There will be no 35k Tesla.

Anyone who got one was merely lucky.

[hndamien]

So we agree that they delivered it.

[MattRix]

He's always late with his estimates (aren't we all), but he sure is determined to deliver eventually.

I'm not always a huge Musk fan, but I don't understand this kind of criticism at all. Going to mars is something the human race hasn't done before, it's no surprise it is taking longer than expected.

[cptskippy]

> It takes the weight of ~5 Model 3s ontop of a single one for the glass roof to shatter. That's good engineering.

But that's not what it says at all. No where does it say the glass won't shatter.

The Model 3 roof has two roll bars, one links the A pillars and the other links the B pillars. That's what's strong.

[w-m]

The roof strength test is performed "by pushing an angled metal plate down on one side of the roof" (https://www.iihs.org/ratings/about-our-tests#roof-strength-t...). So it is the metal body structure that is tested here, not the glass in the center of the roof.

[mc32]

In a rollover the glass might encounter a sharp point (ala “ninja rocks”) which exerts impact on a very small area causing failure, no? Or is their glass capable of absorbing these impacts?

[modeless]

The glass will almost certainly break in a rollover crash. But it's laminated safety glass, so it won't be dangerous. More importantly, the metal frame of the roof acts as a roll cage, and that's what IIHS tests the strength of. They're not really testing the glass.

See pictures of a rolled over Model 3 here: https://electrek.co/2018/07/15/tesla-model-3-rollover-crash/ The glass is broken but the rigid metal frame clearly protected the occupants from harm.

[SEJeff]

https://www.iihs.org/ratings/about-our-tests#roof-strength-t...

[mc32]

Thanks that’s good information. I still have a concern in that it appears this is a controlled pressure (it’s not a sudden violent impact), if it is a sudden violent impact then it’s not expressed that way to me.

Metal gives and then fails. Glass gives minimally, and depending on tempering, can fail very, very quickly.

[SEJeff]

But it is safety glass, and the roof is still re-enforced with metal.

[hanniabu]

I also suspect this isn't a real world value because if you find yourself in an upside down car, chances are it's because you were in an accident. This means the vehicle likely acquired some damage and therefore would likely have a compromised support structure for the glass.

[MFogleman]

Rollover crashes are generally pretty safe assuming the roof doesn't collapse and squish you to death, and you are wearing your seatbelt. The energy dissipates without you suddenly coming to a stop like if you hit a tree. Most of the damage will be from broken windows/debris causing cuts/scratches.

If you are not wearing a seatbelt, you run the risk of being ejected from the vehicle, and the higher risk of being 'partially ejected' from the vehicle, which is often worse.

I personally observed only 1 vehicle where the roof caved in on rollover (I believe it was a mid 2000s mustang). If the driver had been a few inches taller, I imagine he would've been hurt pretty badly.

The only other time I saw a roof collapse in wasn't from a roll over, but striking a tree roof first at a high rate of speed.

The only rollover crash I ever observed that the driver couldn't walk away from was a rather fortunate partial ejection. The vehicle only rolled onto its side, pinning the drivers arm between the road and the door as it slid for a few dozen yards.

The durability of the laminated safety glass should not be understated. A fire department's extraction team's approach is likely to be "cut through the glass with a circular saw".

Granted, all of this is anecdotal, with a very small sample size. Either way, wear your seat belt.

[black6]

Strength and toughness are different properties in materials science. A ceramic mug is strong enough to support great amounts of weight, but it's not very tough. I would think toughness (and elastic modulus) plays more of a safety role in a roof than strength, because strength comes from the pillars.

[semi-extrinsic]

Where is that quote from?

When I open TFA, I can't even find the word "glass" when I search for it.

[weaksauce]

https://www.tesla.com/en_CA/blog/model-3-earns-2019-iihs-top...

Must have been moved from the Tesla press release to the institutes website press release.

[semi-extrinsic]

Makes sense, the language in that quote sounds much more like a company press release. I would have been surprised if the IIHS actually said things like "the exceptional strength". On the contrary, IIHS didn't even find this fact important enough to mention in their press release at all.

[SEJeff]

Tesla's followup on this: https://www.tesla.com/blog/model-3-earns-2019-iihs-top-safet...

[roland35]

The glass may be strong but it is probably not "tough" in a material science sense. Metals and plastics can absorb more force and impact without fracturing which is probably what you want in a crash: http://www-materials.eng.cam.ac.uk/mpsite/properties/non-IE/...

[imeron]

It can also turn orange in certain conditions: https://www.google.com/search?q=tesla+orange+roof

[SEJeff]

It is only the front part, and it is due to being polarized glass, which only manifests when the car is wet. I think it is kind of pretty actually (note that I own a Model 3).

[andrewmunsell]

The Model 3 has gone through several iterations of glass, and some builds actually have nearly the entire roof (including the back glass) turn orange in the rain, but I believe new builds actually have no coloration at all since they changed the glass again.

[cptskippy]

It isn't polarized, it's just an IR filter.

[anewguy9000]

and how many model 3s does it take to shatter a metal roof? im not discounting that the claim is impressive, but from a purely safety point of view, wouldnt you expect even more significant forces on this thing in a crash?

[SEJeff]

Lots of vehicles have less crush strength than the Model 3, and most of them don't have glass roofs. If you recall... the NTHSA testing of the Model S literally broke their machine. The NTHSA said the Model S had the best rollover test (top impact from their machine trying to crush it) of anything they've ever tested.

https://www.roadandtrack.com/new-cars/videos/a5238/watch-the...

To really answer your question, I've arbitrarily picked a few common vehicles with metal roofs.

The IIHS says the Civic roof withstands 13,195lbs of force: https://www.iihs.org/ratings/vehicle/honda/civic-2-door-coup...

A Subaru Outback: 18,533lbs of roof strength: https://www.iihs.org/ratings/vehicle/subaru/outback-4-door-w...

A BMW 3 series has roughly the same roof strength as a Model 3: https://www.iihs.org/ratings/vehicle/bmw/3-series-4-door-sed...

An Audi A5 is only 16,327lbs of roof strength: https://www.iihs.org/ratings/vehicle/audi/a5-coupe-2-door-co...

You get the idea!

[baybal2]

One moment you missed. Electric cars are very heavy, and their centres of mass tend to be right below the cabin.

Having very strong pillars is pretty much a prerequisite for surviving a rollover in an EV.

[SEJeff]

Most people tell me the BMW 330i is very comparable to a Model 3, and its curb weight is 3,582 to 3,764 lbs (per BMW). The Model 3's curb weight is 3,627 to 4,072 lbs (per Tesla).

That isn't as big of a difference as I'd have expected.

[thetinguy]

Engines and transmissions are also heavy.

[moduspol]

They're not all that heavy any more.

The Tesla Model 3 is 3552-4072 lbs, while the new Jeep Wrangler (JL) is 3955-4455 lbs.

[bradlys]

I think it's more of a "relative" to certain cars.

I could compare it to a miata that is ~2300lbs. But that's not really relevant then, is it? A Jeep Wrangler is basically a truck - so I don't think that's a good comparison.

Compared to other "compact executive cars" (as its class states) it's close to the competition.

[moduspol]

Well, I mention it only because I get the comment a lot and my last car was a (two door) Wrangler. You could compare it to trucks, but it's just not perceived as a particularly heavy vehicle even relative to normal cars.

The vibe I've got from talking to people is that they think the Model 3 (or Teslas in general) are significantly heavy relative to normal consumer vehicles. It's pretty surprising to them that even a 2 door Jeep Wrangler is actually heavier.

[baybal2]

Suzuki Mehran dry mass is around 550kg, and it's made of steel, not aluminium.

A more spacious Alto that uses some aluminium and magnesium is around 650kg.

Talking about "not-so-heavy" cars...

[DuskStar]

> Suzuki Mehran dry mass is around 550kg

That's a Pakistan-only car with no safety features [0]. (From the Wikipedia description, "a car with everything manually operated, and with no safety features. The car lacks airbags, ABS, rear window defogger, side air conditioner vents, seat belt reminder and even rear seat belts.") So yes, it's light. You'll also immediately die in a collision, but you get what you pay for I suppose. (The Alto is sold more broadly, but it's still obsolete)

Not exactly comparing like to like.

0: https://en.wikipedia.org/wiki/Suzuki_Mehran

[maxerickson]

The Model 3 is ~25% heavier than Ford Fusion.

[kenhwang]

That's not even that impressive and pretty standard for the industry. The relatively pedestrian Mazda3 resists 18,239lbs, which is 6x it's weight.

Just about every family sedan on the market does >5x body weight.

[peaktechisnow]

Is the Mazda3 roof made out of glass?

[kenhwang]

It doesn't matter because the glass isn't load bearing. Sunroofs are even less rigid and safe than panoramic glass roofs and cars have been passing safety tests with those for decades.

[fucking_tragedy]

What's being measured is the strength of the bars that make up the roof, not the glass.

[lucb1e]

So my phone may not yet have 5G, but my car can definitely pull 5G on its roof.

Sure how many Gs one typically pulls during a car crash. 5 doesn't strike me as a lot, but of course this is specifically about force applied to the roof. I guess you have to not just roll but actually fall on top of it somehow. At any rate, some actual data would be great instead of being amazed at this marketing statement.

[thenewwazoo]

Weight, a force in lbs, is not the same as g-force (m/s^2), which is an acceleration. You can't directly compare the two without knowing the time over which the acceleration occurs (and even then you only get an average force over time).

[ummonk]

The comment you’re replying to correctly used F=ma to impute the amount of sustained acceleration the roof could support.

[prolepunk]

I think the quote mischaracterizes static and dynamic load.

Yes, the roof can hold 5 teslas stack one on top of the other, but this doesn't tell you much.

More practical knowledge would be at what speed the car will fall on the roof before the roof collapses? 50km/h 70km/h 100km/h?

[thetinguy]

That’s pretty much as strong as other cars in the class.

[saiya-jin]

Static load is a nice number, but that's not what car safety test should be about - car crash is a rather violent dynamic event. I guess most common situation is rolling of the car, with possible stop at some wall with roof absorbing most of the impact.

I am not sure tests of such an event would be still so favorable.

Or to put it differently - that's an impressive achievement of a situation that will never happen to a Tesla driver. What about performance in crash situation that might actually happen?

[SEJeff]

Ask literally anyone who's been in a horrific wreck in a tesla and walked away. They're incredibly safe vehicles.

There have been some pretty insane examples of this, such as this one: https://www.autoblog.com/2016/05/06/tesla-model-s-crash-germ...

[kalleboo]

Literally the definition of survivor bias.

[SEJeff]

I guess what I was attempting (and admittedly failing!) to say was that Tesla vehicles hold up very well in very bad wrecks. The cars have tons of driver assist / active safety features, but they also have a huge crumple zone due to not having an engine, and an exceptionally low center of gravity due to the battery. There are many cases where people walk away from bad wrecks in a tesla where they'd have been intensive care or worse in most vehicles.

[whenchamenia]

No doubt! I crashed violently, twice, at highway speeds, in tiny 80s economy cars. Im fine. They must be safe! /s

[kalleboo]

You joke but I've literally heard people make this argument about seat belts.

[rootusrootus]

Go to the Subaru forums and you get similar examples. Modern cars are generally very safe.