Driverless Tesla Car crashes killing two

Why is c o c k pit a banned word?

 

That explains a lot actually. I just don't understand why they recommend water of all things and why nobody is questioning the use of water when it requires such a large amount of water to put out one battery fire. Fire engines typically carry between 500-750 gallons of water. So 3,000-8,000 gallons of water would require between 4-16 fire engines worth of water (if no where near a fire hydrant or other large source of water). The only thing I can think of as to why water is being recommended is because that is what is available to ALL fire fighting organizations. Use the water, not to cool the battery since water and lithium react somewhat violently and create quite a bit of heat and highly flammable hydrogen; but to accelerate the reaction until there is no more reactionary lithium left to provide heat and hydrogen to keep an extinguished electrical fire going.

I think the reason why foam isn't recommended by Tesla to be used on their vehicles is that their electrical systems are not properly insulated and spec'd to withstand the rigors of driving said vehicles. Because of this, I don't think the vehicles are dielectrically tested. If they were, then foam can be used.

According to Safelincs, "Please note that foam extinguishers should only be used on or near live electrical equipment if they are di-electrically tested." They also state that "Electrical equipment should be avoided when using a water extinguisher (unless water with additive are used) as water is a conductor."

CO2 is the most recommended method for electrical fires and can be used on any fires except Classes A and F, since those could spread instead of being extinguished. CO2 doesn't leave any sort of residue and is a non-conducting material. Just don't use it in enclosed locations without proper ventilation due to the risk of asphyxiation.

Dry Powder (ABC Powder) is the most recommended for Class D fires, but it can also be used for Classes A, B, and C along with electrical fires. Used where water shouldn't be used. Lithium, among other reactionary metals, is classified as a Class D fire. Not recommended for enclosed spaces due to breathing hazards. They are also quite messy and not easy to clean up.

Resource for Dielectric Testing.
DIELECTRIC TESTING | Gigavac

Resource for fire extinguishing materials and methods.
How to Use Foam Fire Extinguishers.

Resource for Lithium and Water Reaction
Lithium (Li) and water (lenntech.com)

 

Dielectrical testing refers to the foam extinguisher and agent itself. The whole point is that you should only use a foam extingusher if it is non conductive (dielectrically tested).

The insulation/dielectric properties of the car does not matter one bit, as all that goes out the window once fire is added. Not only does the fire burn through insulation on wires, fire itself conducts electricity.

Really, the issue with damaged lithium batteries is that they self-ignite. Damage shorts them out, and they will reignite even after the flames are out. The best solution is flooding with water.

 

This is ALL just a stepping stone
We can’t go directly to non driver vehicle status
We need to bridge the “ what if “ gap along the way

 

Meh...
Not sure about that
Didn’t Capt Sully make a difference?

 

For those of you questioning the intelligence of the 2 dead men in the Tesla, one of them was a 59 year old physician. Of course that doesn't guarantee common sense, but at least one of the two you would think should have known better.

'He will be dearly missed': Doctor among 2 victims in fatal Tesla crash

Sounds like the two men just dropped their wives off and decided to go for a joy ride and play with the autopilot feature, at least that's what the wives told investigators. Elon Musk has said that according to their data, the auto pilot feature was turned off at the time of the crash, but that doesn't seem to fit the story, since both occupants felt comfortable enough with the performance of the car that neither of them felt it was necessary to be in the driver's seat. More than likely the autopilot feature shut off just before the crash, which you would think should result in the car making a safe stop.

My biggest gripe is the way they market this feature as "autopilot". The name alone gives drivers a false sense of security. When autopilot in an aircraft disengages, the pilot has plenty of time to take control of the plane. When autopilot in an automobile disengages or if it doesn't recognize a potential risk, the driver may only have a second or less to respond, and the human brain simply isn't wired to respond that quickly in most instances, as many of us can attest being professional drivers. Tesla is so sure about their autopilot tech that they're coming out with a $10,000 upgrade for Tesla software they they call FSD or Full Self Driving mode which can supposedly navigate city streets, recognize stop lights and even summon your car to your location from a parking garage. Sounds like a disaster waiting to happen to me.

 

They(Tesla) should just call it what it really is,,,Cruise Control.

 

Because part of a valid and non-offensive word has an 'offensive' word as a part of it.

I guess the programmers that write the censoring programs are not smart enough to do it correctly.

And maybe that is why AI will never be as good as AI.

(And maybe that is why Artificial Intelligence will never be as good as Actual Intelligence.)
?

If there were real people censoring the words, that would (should?) never happen.

 

I started reading this thread and go to about 28 posts before I had enough. I’m sure a lot has been cleared up in the other 7 pages but wanted to point some things out.

the fire was extinguished in approx 4 mins. Due to the nature of lithium batteries burning they continued to be an obstacle for several hours.

water is the primary agent suggested by Tesla, foam does nothing and smothering doesn’t apply. Fact is smothering would need class b foam is for polar solvent fires. You can flow a smothering blanket and that’s a tactic for suppressing vapors too but the foam blankets don’t hold up well to direct flame. The chemical reaction happening with the batteries is tough to overcome. I believe there are approx 7k batteries.

the rear passenger was the driver and had been in the drivers seat prior to impact. This was not a fault of a self driving car

this was a tragic accident that replays daily in the country and garnered literal national attention due to the make of the car and assumption made by the initial law enforcement agency.

I’m just a random person in the Internet but rest assured this is as accurate information as there is from someone that is familiar with this situation.

brett

 

All class A foam is is basically a water wetter. Think dawn soap, reduces the surface tension of the water so it can be absorbed better also creates an insulation of sorts for exposure protection.

In rural settings, depts typically have tankers or tenders that carry up to 3500 gallons of water. Tesla tend to stay in more densely populated areas with hydrants readily available too.

lithium reacting to water is nothing compared to magnesium for reactivity.

when left alone, they will burn themselves out in approx 24 hours

brett