Comment by amai
1 day ago
This video states that it takes 2–6 hours to charge the compressed air for the cold-gas thrusters. And then you can use it exactly once before you have to recharge it. The journalist calls it “beautifully pointless.”
1 day ago
This video states that it takes 2–6 hours to charge the compressed air for the cold-gas thrusters. And then you can use it exactly once before you have to recharge it. The journalist calls it “beautifully pointless.”
The funny thing is that during the event, Elon claimed that the car can recharge the tanks itself [0], but in the Top Gear video, the Tesla folks say that it is recharged from an external source [1]. In the Top Gear video, they also say that they are filling it from a "high pressure nitrogen system", whereas Elon claims that the tank is filled with air. They can't even keep their own messaging straight.
[0] https://www.youtube.com/live/qt5p-_tE8d0?si=V5csPghK02wwd0or...
[1] https://youtu.be/JdkIOhFmbKI?si=ULvyIRWDRZRWlIWA&t=1340
Elon _always_ lies and exaggerates during these things. He seemingly can't stop himself.
I assume it's both...
it has its own pump, but if you don't want to wait 6 hours to recharge, you can fill it with a nitrogen cylinder.
The Top Gear video mentions that kind of recharge time using an external system (though they do claim that they are trying to get it down to 30min).
I've seen some claims that the gas is stored at a pressure of 10000 psi/690 bar in a 200 l tank. If that's true, then that is a gas volume of 138000 l. A commercial, stationary scuba compressor compresses around 850 l/min [0] to 350 bar. A compressor like that would take around 160 min just to compress 138000 l to 350 bar (so significantly less than 690 bar), is a _large_ appliance, and _loud_. Compressing gas quickly also produces heat. An on-board compressor seems quite unrealistic to me unless I'm missing something.
[0] https://www.bauer-kompressoren.de/en_en/pe-ve1
And the car would have 4 seats(now 2), over 1000 km range(now less than half), and be the fastest car period(now very far off). Then they say it will do 300 and something km/h, but also say it will do Mach 0.5. They are completely clueless, as usual.
He's only 78% correct.
promise everything now, work out everything else later.
Perhaps they use liquid nitrogen and then just allow it to boil off inside the tanks? This would give them a safe and easy way to quickly recharge the tanks for testing.
Air is basically nitrogen. It can probably use both.
Based on a cursory search, propellant-grade nitrogen requires a high purity (99.99%) [0]. I am no aerospace engineer, but I'd be interested to know what the actual requirements are for a system like that to work reliably. If 99.99% nitrogen is actually required, then I'd assume that the corresponding compressor would neither be compact nor particularly maintenance-free.
[0] MIL-PRF-27401
Air often contains water though too which could cause problems with ice at the rquired discharge rates.
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It's pretty simple, actually, Elon is a pathological liar.
The stock market agrees. TSLA continues trending downward.
Also, the stock market's id, aka WSB is not impressed in hilarious and sometimes insightful ways. [0]
From my nerd POV, this looks super cool! From any other POV, ummm, what are we supposed to do with this? This is neat as heck, but you cannot put COPVs on public roadways.
[0] https://old.reddit.com/r/wallstreetbets/comments/1x73hxs/tes...
Not trending down anywhere near enough. Their PE Ratio is absurd, but it definitely proves the adage that the market can stay irrational longer than you can stay solvent.
And as a nerd, while it's a cool demo in a controlled environment, cars like that are the last thing I want on the road near me as a driver, passenger, or pedestrian!
I'm not sure if the stock price means a lot. Tesla is kind of a meme stock, people buy it based on vibes, not based on what it's worth.
But this technology is as useless as a toothbrush with a rocket engine. Some rich car crazy guys will buy it, sure. But maybe a few thousand units. This technology doesn't bring any substantial revenue for a billion dollar company. People who own this rocket car it will try it out once or twice and then it will end up in some pretty garage for a few decades.
> people buy it based on vibes, not based on what it's worth.
There's a little secret you should know about the value of all stocks...
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All fancy sports cars are useless. Like really. To race them? What’s the point?
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I mean, this is something we want to encourage. Everyone always likes to quote fiduciary duty ad nauseum. Here is a public company flying (lol) in the face of that in the spirit of, well, fun.
But, this version of the Roadster is just a concept car with many extra steps, isn't it?
What happens when a charged COPV is involved in a car accident?
What is the point of reaction thrusters that turn anyone on the wrong side of the car into pink mist?
Will anyone ever be allowed to drive this on a public roadway?
4 replies →
We're not just talking about "fiduciary duty". Some people put down large (250k) down payments for the Roadster when it was announced 9 years ago. If I were one of those folks I'd be more interested in getting an actual car I could drive than seeing a cool demo.
> TSLA continues trending downward
uh.. zoom out a bit? The stock price is double what it was two years ago
But you'd expect if this were being treated as a likely success for Tesla the announcement would have caused a price bump or at least a reversal of the trend.
Also 2 years ago is a pretty specific time point where it was near the lowest it's been looking back a less random 5d, 1M, 6M, 1Y and 5Y it's only up on the 5Y chart and that's a relatively meager 25%.
5 replies →
I suppose I should have written "continues recent downward trend." One would hope that a huge marketing investment like this would help hype the stock, no?
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It's just a supercar. Supercars are allowed to be pointless.
This isn't the car though, this is a concept demo to keep people subscribed while they continue to delay the real car. I agree supercars are pointless in a lot of ways, but this is just not the same thing because it's vaporware meant to be provocative.
It's a "sports car". At least that is what all the marketing says and has said since forever. Even the title on the website is "Electric sports car". But it's not really a sports car, it's a fantasy car that does not exist, and never will exist.
It's not pointless at all. The car needs wings to become a glider. It doesn't need the fans for downward force or any of the high speed stuff. You take the car as high as you can and glide down. So it would be an airplane first and a car second. That would be seriously cool. The military would use it too. An airphibious/wingsuit vehicle. It could also have a drop-out seat/s for skydiving out of or doing air drops. For landing, another central wheel can be deployed to absorb the main bump or the existing wheels are extended further down. If there's a problem mid-flight there is an emergency chute as well, or can be used if wings not fitted or used.
It could also be made into a water/air vehicle instead and useful for getting over rough seas or air-docking with superyachts or destroyers. Floating/inflatable solar panels would be great too. Another interesting use case would be for airplane passengers and their baggage to leave a plane without the plane actually landing. The landing car could re-dock with the plane on its return flight. That'd be tricky, though.
That sounds fine. Charging time isn't the problem though.
I would say it's beautifully pointless in about the same way that the tires on a Bugatti Veyron are rated for some absurdly low number of km before they need to be replaced, and they can only be replaced by shipping the entire wheels to specialized facilities which are equipped to do them. The whole levitating car on thrusters thing is a specialty novelty for rich collectors.
The obvious use case is to avoid a collision!
Single use is perfectly fine for that purpose. No one complains that airbags are single use.
You can't really predict how a collision would happen and hence where you should land.
I'd say the best way to avoid collisions at scale is already on the road and its cars with sensors and computers, if we weren't living in a pre-cyberpunk dystopia I would gladly have them coordinate to achieve that
As a driver, that would be very hard, but the car could figure it out in a millisecond.
The "air rockets" could probably also be used as hard emergency brakes.
It's a typical Tesla/Elon marketing stunt and nothing more.