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Comment by nonchalance | Hacker News Reader

Amusing how positive stories about tesla take the top spot on HN while news of the fire was quickly flagged off the front page.

Not to question what was said here, but:

> Had I not been in a Tesla, that object could have punched through the floor and caused me serious harm.

How is that the case? There are cars that are higher off the ground than a Tesla (where it wouldn't have a chance to punch through the floor) and most cars have material in the undercarriage to protect against small blows like this ...

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I've been in an old Subaru Justy whose floor pan had been rusting for years, and it wouldn't have stopped squat coming through and hitting the driver. Once, the car's owner was driving us to a music contest, and we started to hear some scraping. He pulled over and pulled a piece of metal off the bottom of the car, and we kept driving.

That's never going to happen with a Tesla S. (Read that both in a good and bad way.)

How old is the Justy though ... compared to a newer model Subaru? I love my Subaru Impreza ... and it is built solid...

In 1992, that Justy was already old. Incidentally, that friend bought that car for $250 his sophomore year. When he graduated, he sold it for $250.

> old Subaru Justy whose floor pan had been rusting for years

Now, if Tesla S floor pans never rust, then I'd agree with your conclusion.

It's not just that. There's very little metal besides aluminum, and it's quite a bit thicker than the steel floorpan. I would expect the battery cases to be much less vulnerable to corrosion than sheet steel.

Aluminium corrodes quite nicely in salty environs.

Pretty much everything does. The question is how fast. When steel rusts, it manages to increase the surface area available to more chemical reactions, which is why rust spreads like a cancer. I don't think aluminum does this.

Under normal conditions, aluminum oxide forms a protective layer for the rest of the aluminum. This goes out the window for unusual sorts of corrosion (say, mercury).

Really? Someone should really tell the manufacturers of boats then.

They know this; that's why zinc sacrificial anodes are used. See: http://en.wikipedia.org/wiki/Cathodic_protection

If your boat is only aluminium you don't really need the anode. it is only when in contact with other metals that aluminium has serious problems in sea water, as it becomes the sacrificial anode to your steel or brass, so you need zinc then as it has an even lower potential.

I think we need to try to define small blows if that's what you're going to call this. They hit a trailer hitch, fast, and it pierced 1/4 inch of steel armor. In a car with similar clearance and without such armor it seems there's a very real chance it could have penetrated the driver or passenger compartments. I don't think that's a small blow.

Are .02% of all car drivers injured every year by road debris which punctures the cabin from the underside of the car? Because that's the percentage of Tesla drivers who claim the design of the car saved them from this very thing.

According to the well-referenced http://en.wikipedia.org/wiki/Road_debris :

> In 2004, a AAA Foundation for Traffic Safety study revealed that vehicle-related road debris caused 25,000 accidents—and nearly 100 deaths—each year.[1][7] At highway speeds, even small debris can be deadly.

With the small sample size so far, we could chalk it up to a statistical anomaly (repeated "unlucky" events do happen, and are expected with natural random sampling), or an actual engineering problem.

My bet is low clearance. It would be interesting to compare these accidents against all cars with similar bottom clearance.

In that case, it's just a physical dimension problem combined with a bit of a poor consequence of battery damage...

Flagged off the front page? The day news of the 3rd fire broke there were two stories that made it to the front page and between them both covered pretty much the entire working day.

This was noted two days ago: https://news.ycombinator.com/item?id=6692051

This is a general trend though: Tesla's overreach regarding the NHTSA rating was on the front page for more than a day, whereas NHTSA's statement regarding Tesla's misinterpretation was not even on the front page for a few hours.

Also>Yesterday (21 points, flagged < 1 hr)

https://news.ycombinator.com/item?id=6697788

And before that... (26 points, flagged < 1hr)

https://news.ycombinator.com/item?id=6566931

Last press release: (567 points, #1 front page)

https://news.ycombinator.com/item?id=6497478

That seems to be more the result of the overzealous flame-war detector rather than the effect of flagging. Only PG can truly tell, though.

The flamewar detector brings the story down if it has a lot of comments, and if not paired with lot of upvotes, takes it quickly off the front page. So, while you're right about the HN bias(lack of upvotes), you're wrong about the reason(flamewar detector rather than flagging).

It also tends to happen to Gruber articles, articles positive or neutral about Microsoft, and anti-Samsung or anti-Google articles.

Here's a couple of examples.

http://hnweird.tumblr.com

HEADLINE: Tesla Fire Sets off Flamewar.

MOUNTAIN VIEW, CA. HN headquarters was forced to shut down earlier today when a Tesla Model S (discussion) spontaneously caught fire. Responding the the event, the mountain view polic chief was on the scene within minutes. According to source, PG tried to put out the fire using water (in line with TSLA protocol), but the stubborn flames kept re-igniting. Finally, he had to revert to "flipping the server over" and drilling a hole in the bottom to finally douse the flames. No injuries were reported in the incident, and PG will be writing an essay later this week on the subejct. Extolling the cirtues of the Flamewar detector, as well as the excellent design of the electronically powered server at the heart of the matter.

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