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Man In Tesla Model S Fire Explains What Happened
An anonymous reader writes "The three recent Tesla fires have raised concerns with a lot of people. One person who isn't concerned, however, is Juris Shibayama, the man whose model S burned in Tennessee. He says: 'I would buy another one in a heartbeat.' From the article: 'Shibayama said that he struck a three-pronged trailer hitch in the middle lane of the interstate. He continued: "About 30-45 seconds later, there was a warning on the dashboard display saying, 'Car needs service. Car may not restart.' I continued to drive, hoping to get home. About one minute later, the message on the dashboard display read, 'Please pull over safely. Car is shutting down.'" He said he had time to remove his possessions, even though, he said: "About 5-10 seconds after getting out of the car, smoke started to come from the front underbody of the car."'"
Gas tanks don't need 1/4" armor ... because they don't mount them where shit getting wedge under the car is going to penetrate them, neither should you.
Obviously you haven't looked under a car before. Most gas tanks are mounted under the rear seat and VERY exposed, having only a couple straps and..... a piece of sheet metal (for a heat and debris shield) to protect it. (tanks nowadays are mostly made of plastic as well, so the casing on a battery is probably stronger. the plastic is soft, and flexes, so that helps)
One of these, perchance? http://www.harborfreight.com/triple-ball-trailer-hitch-69874.html
Program Intellivision!
You are correct that Tesla needs to analyze why the batteries are being compromised from what should be survivable incidents, a car's batteries should be protected better to keep them from being damaged by even the most severe road debris.
Actually, the described scenario of striking a multi-headed trailer hitch is probably WORSE than all that you described. It must of acted like a huge caltrop. You can't design for 'everything' and keep the car light enough to be functional.
Concrete curb - Odds are at least one of the wheels are going to hit the curb as well, raising the vehicle and lowering the strike area, and standard ones probably don't stick up as high as the hitch did. Even if not, you likely have a deflecting implact, not a puncturing one.
Road sign - These are generally constructed of mild steel and aluminum, as the worst the post has to withstand is the weather on the sign. In an impact it's going to be forced down of course, but then the rest of the sign will act as a lifting/distributing force on the car.
Trailer hitch - Designed to be able to haul trailers weighing 5k pounds and up, the balls are solid hardened steel and the post is generally at least 1/2 inch thick, again of hardened steel. Given the described hitch was a multi-ball type, it's entirely possible/probable that the thing weighed more than the average stop sign/post(excepting concrete), much less a mile marker. It probably impacted the car in a armor-piercing fashion much like a pike against a calvary charge.
I don't read AC A human right
On a more serious note, you should read the actual post and not just the couple sentences.
Here's probably the most revealing item in terms of how safe the car is:
The firemen arrived promptly and applied water to the flames. They were about to pry open the doors, so I pressed my key button and the handles presented and everything worked even though the front of the car was on fire. No flames ever reached the cabin, and nothing inside was damaged. I was even able to get my papers and pens out of the glove compartment.
So, guy runs over hitch in the road doing 70mph, it damages the car, the car tells him to pull over, and even though it no longer accelerates it still steers and works 100% normally. Car starts smoking a few minutes later, so he sits around and watches it burn until the fire deparment shows up, and even while it's on fire it still works and doesn't even get enough heat into the passenger area to melt the cheap plastic pen in his glove box.
If it wasn't $100k, I'd buy one tomorrow. Shit, we just had a guy in my town catch his truck on fire (leaky fuel line they think) and he pulled over, had 2nd degree burns by the time he got out of the cab, and watched his truck burn to the ground within minutes.
Yeah its not as if petrol/diesel cars ever catch fire...
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/36467/FSGB_2011_to_12.pdf
http://webarchive.nationalarchives.gov.uk/20120919132719/http://www.communities.gov.uk/pub/894/FireStatisticsUnitedKingdom2003PDF1724Kb_id1124894.pdf
14,000 or so in the UK last year, which is a massive drop from the 28,800 in 1993 and those are just the accidental fires...
Newsflash: technology gets more reliable over time and the Tesla is still brand new compared to internal combustion that has had over 130 years of safety problems, development work and improvements. How often do you hear of mobile phones and laptops bursting into flames these days? For a while it seemed to be happening all the time...
[The Universe] has gone offline.
Initially I would think the fuel is more flammable than the batteries, but I have no research to support that.
The difference is that the batteries can ignite without an external heat source. As in the case mentioned, if the battery short-circuit for any reason, it can ignite. Fuel needs an external heat source to ignite. :-) ).
Liquid fuel is actually not easily ignited (do not believe what you see in movies
One other factor is how a fast a fire becomes dangerous. If the fuel ignites, you are in big trouble NOW. If the battery ignites, it is quite likely not immediately dangerous, as the flammable material does not spread.
Different energy stores, different risks.
And yet the driver not only kept driving after the impact, but then (after the second warning) had time to pull over, collect his things and calmly get out.
And after the fire, which was easily put out, he recovered his other possessions from the car, which were all unburnt because not only did the fire never breach the passenger compartment, the heat from the fire never reached it. Theoretically, he could have sat in the car the whole time. I've only seen one vehicle fuel fire, and even though the fire dept was there in a few minutes, there was nothing left afterwards but bare metal.
Science is all about firing a drunk pig out of a cannon just to see what happens.
If road/car safety was left to the "invisible hand" then people would still be driving around with "DIY LPG conversions"
If you had any idea how many DIY LPG conversions there are running around on the roads right now, you would apparently piss yourself. And besides conversions, it is hilariously common for people to do DIY propane systems on their diesels. Apparently it provides a power boost similar to a turbo, and propane is cheap these days so it's cheaper than using a turbo to burn more diesel. A grill tank goes in the bed or sometimes in a toolbox and gets connected with some more grill parts, like a grill regulator and nozzle. These systems are relatively trouble-free so long as they're installed such that the line isn't run someplace idiotic.
As well, you can get a propane conversion for pretty much anything carbureted for about $250, not counting the fancy tanks you have to have for road use.
I've run a 2.5 HP briggs and stratton four stroke by connecting a nipple to a camp stove (throwaway) cylinder and running a piece of 1/4 inch tubing into the carburetor. The nipple is based on a torch head that fell off, so there's a valve there. You can control motor speed by turning the valve, simple as that. The conversions use a vacuum-controlled valve, so the engine draws the fuel it needs and you control the butterfly in order to control the engine as normal. Anyone competent to turn a wrench can perform a conversion and again, there's currently significant cost savings in running propane. It's 2.50 per gallon-equivalent on one of the local reservations right now.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Except, these vehicles are being held to the high standard of --- will not explode or be dramatically less safe, after a minor accident, than an ordinary gasoline-fueled vehicle.
Driving over a 3-way hitch at speed on the freeway and having it come up and strike the vehicle is not a minor accident. That could easily have damaged a suspension component or punctured a fuel tank in a gasoline vehicle. In an extreme case, it could bounce up on end (stranger things have happened, and I've even seen some of them) and the vehicle could sort of pole vault on it, with unpredictable consequences; it might end up stuck through a floorpan, or just put a massive dent in one. Nobody can possibly tell.
In the case of this accident, it appears that it did jump up on end, because it apparently punctured the big plate which protects the batteries. That takes enough force to take this well out of the range of "minor accident".
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
So I did a little math. I know, a bad habit, but I can't help myself.
In any case, I was curious as to the numbers behind the recent Tesla vehicle fires and how that compares to the rest of the vehicles on the road.
So last year 21,500* Tesla vehicles where sold. To date there have been 3 fires. That makes 21500/3 equals roughly 1 fire out of 7167 vehicles. That looks pretty bad, wow. Tesla vehicles must be terrible. Right?
For comparison, there were 194,000** vehicle fires between 2008 to 2010 or to oversimplify things 97,000 per year. And in 2008 there were roughly 256 million*** vehicles on the road.
256000000/97000 equals about 1 fire out every 2639 roadable automobiles. Doh!
It appears that it is almost three times as likely that any random vehicle on the road will catch fire than any random Tesla. That bears repeating. You are just about 3 times safer from dying by fire in a Tesla.
And yet another sensationalist story that the media is getting wrong.
* http://www.forbes.com/sites/hannahelliott/2013/11/05/tesla-up-9-as-production-hinders-growth/
** http://www.usfa.fema.gov/downloads/pdf/statistics/v13i11.pdf
***http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_01_11.html
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