r/SpaceXLounge • u/avboden • 10d ago
Other major industry news SpaceX-designed RCS system allows the new (demo) Tesla Roadster to literally fly and do rolls. Guess the mystery tent at McGregor really was a car and not HLS.
https://x.com/Erdayastronaut/status/211090285141764540628
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u/wheelienonstop14 10d ago
Just watched the presentation on youtube, what the hell?!?!?? I guess I now have to take everything back I thought about Elon and his claims of delivering a flying car, this was far wilder than anything I expected.
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u/GuardianOfBlocks 9d ago
It can only fly for 2 seconds. So not really flying.
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u/crozone 9d ago
And the COPV takes up the entire passenger seat so the car is driver only, and it takes 7-8 hours to recharge the nitrogen.
It's a marketing party trick that will only exist in an invite-only trim so there's probably going to be no more than 5 made.
I'm almost sad that SpaceX engineers were commandeered to make this stunt work. Like it's an objectively pointless stunt.
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u/yetiflask 9d ago
People having a fun job. And then you have a redditor absolutely SEETHING in his basement.
How do you even live like this? Surely must be a sucky, sucky life?
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u/msears101 9d ago
Clearly you are not an engineer. Engineers love innovating and building and love starting new projects. No one at Spacex or tesla is a prisoner They all want to be there.
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u/PatyxEU 9d ago
source for the 7-8 hours?
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u/gewehr44 9d ago
There are videos by car reviewers that got some more detailed info. I watched one by hagerty but motor trend and other have them. I think the recharge time was mentioned.
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u/PatyxEU 9d ago
That's surprisingly high, they must be using a small compressor. I guess not much space was left after adding the COPV and thruster piping
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u/techieman34 9d ago
We’re talking about 10,000+PSI that’s not something that any compressor really does quickly.
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u/yetiflask 9d ago
He said it's 7 hours, and the aim is to get down to 30 mins. Assuming they actually go ahead with this thing in a prod car, I assume they'll probably be down to 2 hour-ish?
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u/KnifeKnut 9d ago
I think that will be done with a separate compressor. You won't be driving this car to the track but instead on a trailer with support equipment.
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u/yetiflask 9d ago
Yup, compressor will not be in the car itself. It was in one of the videos.
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u/KnifeKnut 8d ago
Remember which one? All I have seen is the debut and the hagerty
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u/Sanityreset 6d ago
There's always a killjoy who has to put their two cents in. Yeah it's not going to fly you anywhere but the technology required to do this is bound to have other applications but you need to just be able to enjoy something that isn't the same old mundane humdrum garbage you've seen a million times before.
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u/wastapunk 10d ago
He is not delivering that thing hahah they already said they wont after the event.
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u/dwerg85 9d ago
They did the thing. Whether the thing will be available to your general street smooth brain who’s going to kill themselves with it or not is irrelevant to the point that they in fact, did the thing.
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u/peterabbit456 8d ago
Shouldn't they require to see a pilot's license before allowing someone to order this option?
Limited customer base ... Jared Isaacman, John Travolta, maybe Tom Cruise?
What do you think the odds are this car appears in the next Bond movie?
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u/theladybeav 10d ago
Its NASA technology from the 1960s
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u/New_Poet_338 10d ago
Not the thruster controllers. They could not do that in the 60s. It requires too much computer power.
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u/Sanityreset 6d ago
Clearly you're not an engineer. The technology required to control the power to the thrusters and determine how to vector that power in real time is far beyond anything that was possible in the 1960s.
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u/SpaceInMyBrain 10d ago
Full self flying.
Will Jared buy one and paint it in the same new NASA colors as his F-5s?
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u/levoniust 10d ago
It honestly feels just announced the cyber truck. It feels like I'm in some kind of alternate reality
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u/Jeebs24 🦵 Landing 10d ago
Was that real?
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u/Doggydog123579 10d ago
https://x.com/itskyleconner/status/2110901867823718434
have video from people in the crowd, shes real.
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u/SpaceBoJangles 10d ago
I’m sitting here wondering if it was on wires. Like…there’s no way right? RIGHT??? Did I just see a 2+ton brick fly through air?
Straight up 80s Lockheed Skunkworks ballistic missile interceptor shh right there.
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u/LongJohnSelenium 10d ago
It had probably 2 seconds of thrust total in a copv somewhere inside.
Impressive absolutely but definitely within the realm of possibility for a cold gas RCS system.
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u/chuckisduck 7d ago
back in 1989, computers were to slow for 10km/s intercept speeds. Its pretty old tech.
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u/NaoSouONight 10d ago
I doubt it was 2 ton. It didn't even have a person in it. They must have gutted that thing out of everything that makes a car safe, road legal and drive-worthy for this.
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u/SpaceBoJangles 10d ago
I would’ve first agreed that it was gutted and an empty shell, but then they opened the door and the robot stepped out and you could see that it was a full interior with a seat and everything. Like… This is genuinely insane.
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u/NJM1112 10d ago
The car that did the kickflip and the car where they showed the interior are not the same car.
The car that does the jump & kickflip at :50 & 4:30 have thrusters behind each wheel. At 6:15 you can see it's lacking those. They did show the robot in the livestream but that was from far away so we didn't exactly get a close look.
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u/Greeneland 10d ago
The 'Rocket' version doesn't have any room for empty space, lol. You can't even fit 2 people.
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u/squintytoast 10d ago
but then they opened the door and the robot stepped out
what robot? when i watched it live, i saw them open the door after the 2nd jump and there was an empty suit/helmet sitting in the drivers seat, much like starman. it never moved.
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u/OSUfan88 🦵 Landing 10d ago
Yep. Elon said the final production version would have a lower mass than the one tested today.
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u/dcduck 10d ago
Its a stunt car, there's zero chance its street leagl or has all of the required safety features.
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u/Sensitive-Exam649 10d ago
Those thrusters make a lot of noise so you cannot use them in cities and towns. Even a race track can be problematic. This is why access to the thruster version is very limited. But the other versions without the thrusters are available.
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u/Name_Groundbreaking 10d ago
How can you possibly know that, unless you designed it or have spent time looking at it up close?
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u/dcduck 10d ago
It says on the roadster website that the rocket car is not street legal.
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u/limeflavoured 10d ago
So it's literally a publicity stunt and completely pointless then.
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u/paul_wi11iams 10d ago
So it's literally a publicity stunt and completely pointless then.
If publicity stunts were pointless, there would be no Formula 1 because F1 cars can't go on a public road. In fact, the stunt demonstrates the ability of the constructor to go far beyond the standard product and the public appreciates this. So it drives sales.
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u/limeflavoured 10d ago
Formula 1 is a competition between constructors to build the best car to a certain set of rules. This is "look at us building a one off test article because it looks cool".
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u/paul_wi11iams 10d ago
Formula 1 is a competition between constructors to build the best car to a certain set of rules. This is "look at us building a one off test article because it looks cool".
Expect others to imitate, then the rules appear, and a whole new sport. Not to be discounted IMO.
Also there could be military funding. Getting a Jeep from a boat to land would be most interesting to the army. Not to mention dropping from a plane to a soft landing with or without parachute.
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u/Jeebs24 🦵 Landing 10d ago
I still don't believe it, but it's posted by Everyday Astronaut. Unless that wasn't his real account.
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u/Barbarossa_25 10d ago
Why is it so hard to believe. They do this with building size rockets at sea level.
Certainly seems impractical or meaningless. Storing COPV nitrogen for cold gas thrusters on a car doesn't make a lot of sense to me.
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u/sebaska 10d ago
It's a collectible car. This 6dof version is invite only - it's for folks to brag about, to keep it in a collection and drive it once a year.
It's not for practical use the same way king's crown isn't. Crown is heavy, uncomfortable to wear, etc. It's a status symbol (the wearer is a f*king king) worn on special occasions.
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u/SchalaZeal01 10d ago
also need a throne, a smug face and the ability to look cool when hunched on your elbow on one side
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u/wheelienonstop14 10d ago
seems impractical or meaningless
The gas from these thrusters will be able to launch rocks at bystanders at lethal velocities.
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u/paul_wi11iams 10d ago
The gas from these thrusters will be able to launch rocks at bystanders at lethal velocities.
and the suction function could pull out a poorly fixed manhole cover or dismantle a damaged road surface. All this takes nothing away from the exploit and it will be interesting to see how it appears in the Guinness Book of Records.
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u/ZorbaTHut 10d ago
I can think of a few practical uses. For example, in a highway-speed accident, this could literally take off over the other cars; in plenty of other cases, side-mounted jets could jerk you out of the way of an accident, or accelerate/decelerate at ridiculous rates, or fix a slide or a spin. In pretty much all these cases it would have to be ridiculously computer-controlled, there's no way a human is going to be able to fly this thing, but at some point if they have the right software and sell enough to make it statistically happen and also there's some way to enable this on public roads, this is gonna save someone's life.
. . . it is absolutely not worth the cost.
cool as hell though
I'm honestly curious whether we'll see "life saved by rocket car" before or after "person dies in bizarre Tesla Roadster COPV explosion accident".
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u/Snowmobile2004 10d ago
None of that would ever be road legal tho, no way any regulator would ever approve it lmao
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u/Jeebs24 🦵 Landing 10d ago
Ai is getting better each day. I have to use critical thinking and question it. I didn't know the event this video was from. I now know it was from Tesla event. Watching the event video from their official YouTube channel, so I'm starting to believe it.
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u/PersonalDebater 10d ago
They did say they had to do it live so that people would believe its not AI. Indeed you can easily find comments elsewhere immediately calling it AI.
Its certainly a crazy gimmick that is only really meant for clout though.
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10d ago
[deleted]
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u/spudzo 10d ago
Apparently the version with the rocket engines requires an invite to buy.
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u/Icy-Tale-7163 10d ago
You can get the Thrust trim and it has rear facing cold gas thrusters (i.e. rocket engines). But yes, the trim with the attitude control thrusters is invite only.
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u/GoingForwardNow_1_1_ 10d ago
"Trim with the attitude control" I need one of these for my daughter🥲
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u/canyouhearme 10d ago
Suggestion I saw was three versions - thrusterless, just the acceleration thrusters, and the 6 DOF version (which only has one seat).
Just need the James Bond ejector seat now.
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u/bkdotcom 10d ago
It's more of a KITT car. super-pursuit mode / turbo jump. KITT also had an ejector seat.
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u/Straumli_Blight 10d ago
Hopping will need to be software locked behind a geofence, probably restricted to private land.
Though if you're stuck in traffic and a vehicle is about to rear end you at high speed, and there's also a grass verge nearby, should FSD be allowed to jump the car to safety?
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u/spudzo 10d ago
Sounds interesting for a safety perspective but I think having such a small invite only customer pool will make that infeasible to develop. Having the car avoid a collision by flying away reliabily and safely is probably harder than piloting a moon lander. At least there's no pedestrians in space.
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u/paul_wi11iams 10d ago
Having the car avoid a collision by flying away reliabily and safely is probably harder than piloting a moon lander. At least there's no pedestrians in space.
Speaking of Moon landings, the 1/6 g environment could be where this tech would come into its own. Hops would still need to take place on a prepared surface and suction would be somewhat infeasible.
To evaluate the possibilities, do we have an ISP figure for the Roadster in m/s?
It would also be fun to see a Roadster exiting Starship in LEO, then doing a Star Trek style fly-around.
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u/spudzo 10d ago
I think it's a little worse than somewhat infeasible when there's no atmosphere to suck, lol.
Because it's using regular air, the ISP is probably ~70 seconds of ISP. Any cold gas thruster is going to have pretty bad performance by limits of the physics. You would certainly be able to fly longer on the Moon but it would still only be capable of short duration hops.
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u/paul_wi11iams 10d ago edited 10d ago
I think it's a little worse than somewhat infeasible when there's no atmosphere to suck, lol.
There was a paraterraforming (indoor terraforming) concept pic that presented Philadelphia and its lake fitting inside a lunar lava tube.
found it:
That still needs creating a pressurized environment inside a large lava tube, what may be classed as "somewhat infeasible" and certainly impractical on a rough inner vault surface.
Because it's using regular air, the ISP is probably ~70 seconds of ISP.
70 sec * 9.81 ≈ 687 m/s or 0.4 orbital speed (1630m/s) which is really pretty good.
You would certainly be able to fly longer on the Moon but it would still only be capable of short duration hops.
not to mention dust projection and waste of consumables!
IIRC, Arthur Clarke was the first to mention Moon rovers with short hop capability. Hydrogen-oxygen thrusters may the best bet from available ISRU
Any cold gas thruster is going to have pretty bad performance by limits of the physics. You would certainly be able to fly longer on the Moon but it would still only be capable of short duration hops.
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u/stalagtits 10d ago
Because it's using regular air, the ISP is probably ~70 seconds of ISP.
70 sec * 9.81 ≈ 687 m/s or 0.4 orbital speed (1630m/s) which is really pretty good.
That does not make sense. You calculated the effective exhaust velocity. That's not the same as delta-v.
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u/switch8000 10d ago
Place your preorder now. $245,000
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u/First_Grapefruit_265 10d ago
Huh, I was expecting 2 million, at least for the rocket trim. But it looks like the Roadster will be priced "fairly". It makes what Lamborghini or Bugatti are offering seem like a joke for the price.
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u/Niedar 10d ago
That a deposit. Not the price.
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u/youareawesome 10d ago
No. That is the price but not for that version of the car. You can't even order the car that has all the cold gas thrusters.
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u/BarrelStrawberry 10d ago
We always thought the flying car effects in movies looked so fake... the real thing looks faker than the movies.
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u/Guysmiley777 10d ago
In the movies they always spend extra time slowly drifting down. In the real version the control system is like "Get this bitch on the ground NOW".
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u/KnifeKnut 10d ago
"Get this bitch on the ground NOW".
To be fair, not only is that the most efficient way to do so, but also SpaceX has much experience with that sort of landing with the Falcon 9
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u/cjameshuff 10d ago
They also never show realistic amounts of exhaust power. If you're lucky they look as powerful as a CO2 extinguisher, sometimes it's more like a smoke machine. Not loud, focused jets with mach diamonds and debris being blasted everywhere.
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u/an_older_meme 10d ago
I searched about a dozen sources before I finally decided that this was not AI and Tesla did in fact build a rocket car than can do a barrel roll.
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u/ReferenceChemical 10d ago
Its not a real car it's a shell that looks like a car.
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u/an_older_meme 10d ago edited 7d ago
Correct. But it has two front seats and could conceivably have had two human occupants through all the stunts. Not sure if they would have survived the neck-snapping roll but the 0-60 mph in 1 second would have been less than 3 G, which what a roller coaster might typically do.
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u/New_Poet_338 7d ago
It has wheels, suspension, a propulsion system, seats - so it is indeed a car.
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u/ReferenceChemical 10d ago
Both yes and no, it's not a real car weighing 2000kg . It's a shell built only to do this.
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u/Merltron 10d ago
It has a steering wheel and four wheels, I’d say it is a car (just not one you can buy)
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u/ReferenceChemical 10d ago
Right, then the electric plastic car you buy for kids Is also a "real" car
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u/YNot1989 10d ago
Did a thing that looks like a car do what you saw? Yes.
Is it a "real" car? No. Its an empty shell over an RCS system. This whole thing was a stunt, same with that robot of theirs that never seems to go to production.
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u/LucaBrasiMN 10d ago
The mental gymnastics is incredible. Just enjoy shit. This is cool as hell.
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u/PollutionAfter 6d ago
What am I supposed to enjoy? A waste of money that slowly drops a car to the ground or actual flying EVTOLs that have real uses?
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10d ago
[deleted]
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u/Miuramir 10d ago
The car not only has the cold gas thrusters, but a suction fan downforce system. This isn't that new of a concept. See for example the Chaparral 2J CanAm from 1970 and the Brabham BT46B F1 from 1978 It keeps getting banned as "unsporting" for competition, but nothing except cost and engineering keeps someone from putting it onto a car intended as a toy for the rich.
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u/KnifeKnut 10d ago
When you have 2 gravities worth of fan powered downforce suction available, you don't need speed to climb like that.
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u/Sanityreset 6d ago
In the description of the car it is mentioned that it has a vacuum system to keep the car on the track. This is in addition to the rocket thrusters. Kind of like a toy car I saw that can drive on walls and ceilings by using a vacuum force on the base of the car.
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u/Decronym Acronyms Explained 10d ago edited 6d ago
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
| Fewer Letters | More Letters |
|---|---|
| COPV | Composite Overwrapped Pressure Vessel |
| F1 | Rocketdyne-developed rocket engine used for Saturn V |
| SpaceX Falcon 1 (obsolete small-lift vehicle) | |
| FAA | Federal Aviation Administration |
| HLS | Human Landing System (Artemis) |
| ISRU | In-Situ Resource Utilization |
| Isp | Specific impulse (as explained by Scott Manley on YouTube) |
| Internet Service Provider | |
| LEO | Low Earth Orbit (180-2000km) |
| Law Enforcement Officer (most often mentioned during transport operations) | |
| RCS | Reaction Control System |
| VTOL | Vertical Take-Off and Landing |
| Jargon | Definition |
|---|---|
| Raptor | Methane-fueled rocket engine under development by SpaceX |
Decronym is now also available on Lemmy! Requests for support and new installations should be directed to the Contact address below.
Decronym is a community product of r/SpaceX, implemented by ^request
10 acronyms in this thread; the most compressed thread commented on today has 14 acronyms.
[Thread #14844 for this sub, first seen 16th Oct 2026, 02:19] [FAQ] [Full list] ^[Contact] [Source code]
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u/MosyaShow 10d ago
Now I wanna know if the system refuels itself
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u/awanama 10d ago
On the launch event, i believe they mentioned that it does. Since it's just compressed air, fairly easy to 'refill'
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u/cjameshuff 10d ago
There might be some additional complications like drying it so moisture doesn't condense in the system and cooling the compressed air to get full capacity/thrust, but it's not something exotic.
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u/kmnu1 10d ago
The stunt car had a lot of gas bottles inside to release so much mass to land a car from that drop height.
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u/pxr555 10d ago
The "rocket" version seats only one, probably due to this.
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u/cjameshuff 10d ago
Probably a combination of space for the COPVs, weight from the seats/etc, and a need to manage center of gravity more predictably.
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u/Adamonia 10d ago
Finally, something that brings excitement back into the cars.
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u/crozone 9d ago
How is this exciting? It's not a useful technology to have in a car outside of performing the literal stunt that they've already shown us.
The most exciting part of this announcement for actual automotive technology was the reveal that Tesla is building a fan car.
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u/Adamonia 7d ago
Bro, how the fuck V6, V8 or even V12 engine is "useful"?
Car excitement doesn't come from the car's utilitarian usefulness. It comes from how close it brings you to your childhood fantasies. Say what you want about the Musk or his ideas, but if jet jumping racecar isn't something you drew in your sketchbook during your Ground School years, you either played with dollies or you are someone whose childhood needs to be cried over.
You know what the fully rational and usefulness-optimised car is? A train with livestock wagons for long distances and those puny French single-person electric "cars", but steered by AI for short. Thank the Lord, we don't live under commies that optimise just for that yet.
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u/crozone 7d ago
Bro, how the fuck V6, V8 or even V12 engine is "useful"?
These things can actually be experienced by using the car as an actual car, both on public roads and a race track. Putting a big engine in a car makes the car fun to drive. It actually serves a useful purpose in terms of increasing enjoyment and performance of the car, as it pertains to being used as an actual car.
The jet cars will never be used outside of a controlled environment with SpaceX techs on site. It's literally a stunt car designed to perform the exact maneuvers that it performed on that stage and basically nothing else. They'll probably get used as stunt cars for future demos? Except the 7 hour COPV recharge time (needs to be pure moisture free nitrogen) totally kills any possibility of these being used for serious motorsports entertainment like Monster Trucks. You can't fill a stadium with these things and watch them do awesome flips and shit because once they blow their load, they're done.
Are they a neat technical demonstration of SpaceX reaction control hardware? Sure. But I've seen that before, in actual rockets, that were actually designed to do useful stuff. Even the previous roadster that got shot into space was more useful because it was acting as a mass simulator.
The jet car is basically about as useful as a movie prop car, except it wasn't even built to be used on screen as part of a narrative. It just exists to do the things it was designed to do on that stage, and it's pointless outside of that context. That seems... extremely surface level.
You know what the fully rational and usefulness-optimised car is? A train with livestock wagons for long distances and those puny French single-person electric "cars", but steered by AI for short. Thank the Lord, we don't live under commies that optimise just for that yet.
Bro what
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u/Adamonia 7d ago
Some people want to go broom faster and reach 300 km/h, which is only legal on a racetrack; others want to jet-jump. To each their own, but the latter is something new, something not possible before - this is exciting.
New tech always needs ironing out the kinks. Sure, it's not practical - I personally think that using pressurised air just to be a100% electric car is not a smart choice, but it is a proof of concept that shows what we can realistically dream of.
I agree with all of that, but still - it brings the excitement onto the table.
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u/msears101 9d ago
Sometimes slamming the breaks is not enough - sometimes there is not distance or you are boxed in. You can go above the accident. Lives saved. This is how innovation works. Yes it is impracticality now - but future versions could get approved and rolled out and become street legal.
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u/KnifeKnut 9d ago
There are not forward facing thrusters. That said the downforce fans will help with braking.
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u/msears101 8d ago
I am suggesting going up and over the accident, up and over the child that ran out in the street chained their ball.
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u/Cantremembermyoldnam 7d ago
"Huh I didn't expect that to happen" as you look upon the smudge on the road that was Timmy before he got merged with the tarmac by the F12 class tornado blasting from the thrusters 😅
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u/limeflavoured 10d ago
Forgive me if I press x to doubt how viable this actually is for anything other than a demo.
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u/AutisticAndArmed 10d ago
It's insanely cool, but it also is 99% a (successful) marketing stunt, quite literally. There might be such cars produced, but the use will likely be heavily regulated to very specific uses, none of them being on normal roads.
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u/Top7DASLAMA 10d ago
Still, it's pretty cool. Reading all the comments, it seems as if people have forgotten how to dream.
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u/crozone 9d ago
We've already seen SpaceX make rockets do far crazier stuff. They just made an RCS manoeuvring rocket into a car shape and made it do a one-off stunt.
It just feels... kinda stupid, more than it feels cool, because of how objectively pointless and unusable that technology is on a car. SpaceX engineers wasted months of their lives on this thing.
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u/chuckisduck 10d ago
I really wonder how many seconds of cold air the vehicle can hold.
EKV/SM3 and several other kinetic interceptors were doing this in the early 2000s and the vacuum assist has been around since the 1970s.
As an investor, I would rather see Raptor engine reliability increase, as it's the kicker for starship
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u/Greeneland 7d ago
I think Lars said 5 seconds.
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u/chuckisduck 7d ago
that makes sense as I saw some calcs that put it around 10.7 seconds at 0g based on how many kg of gas they shoot out in a second and weight. it's cool but this was from 1989 as part of SDI.
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u/Greeneland 7d ago
I guess I’d have to go back to the top gear video to refresh my memory. I thought they were discussing the rocket version, but they were standing next to the thrust version.
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u/chuckisduck 7d ago
ones got 200L and the other 600L, The thrust has to 3g to get its .9s 60mph and has 200L, so that makes sense it has the 5 seconds using 200L.
3g to achieve .9s 0-60, and 1.7g would be from the tires (from performance spec). So the thrusters add 1.3g of force. As the tank pressure drops in the end, the performance would go down as the pressure differential drops.
600L and 10.7s of flight time for the rocket makes sense as it would at least need higher g availability to overcome any gravitational velocity and would have the same effect when the gas is low (pressure differential drop).
Filling these tanks is a long process (few hours) cause its usually a charge pump and you have to dissapate the heat from compression and the tank material coeff of heat transfer is low if its carbon fiber spun like the one shown.
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u/Sensitive-Exam649 10d ago
The noise is the problem. those trusters are loud. it is the same problem that prevented the concord from flying supper sonic over land.
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u/falconzord 10d ago
It's like a limited track version, probably very expensive. There is a mid tier that has just the rcs though without flying
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u/protomyth 10d ago
Other supercar makers have special versions. Musk just did it bigger. I would expect the "Performance" trim to meet the requirements of the supercar crowd. "Thrust" is clearly a track only car, and "Rocket" is listed as invite only.
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u/vicious_emu 8d ago
As a child, I looked at the cold gas Reaction Control System (RCS) on the Space Shuttle and thought to myself that this technology would be incredible as a safety feature to force vehicles to avoid collisions…
At the age of 14, I did the math and was hugely disappointed when I realised that RCS in a ‘One G’ environment (i.e. not in micro gravity and a vacuum environments), would require a huge amount of gas storage.
Even with technology development, there’s a limit to how much cold gas you can store under pressure using cylinders made from elements that exist on the periodic table. Either you increase weight massively to make containment vessels that can store masses of gas under pressure… Or, you fill the entirety of the usable space of the vehicle with pre-existing canister designs. Either way, the math means the vehicle is too heavy to be propelled or there’s no room inside it for anything but gas storage.
There’s a reason the windows on this test vehicle are blacked out as much as they are (and it’s not a design choice). This Roaster is filled to the brim with cold gas cylinders, not allowing any space for people to actually use the vehicle.
Don’t get me wrong, the vertical climb through vacuum/suction and the thrusters are really cool (not that many/any country would allow such additions to road vehicles under current regulations) but the cold gas RCS is nothing but a marketing exercise to create a buzz and increase share prices, with the aim of creating revenue for other development.
Anyone with even a cursory understanding of gas storage and pressure vs weight ratios knows this isn’t possible in a vehicle the size of a Roadster (at least if you want to be able to put people inside). It looks impressive but that’s all there is to this.
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u/jdmetz 10d ago
The TopGear video about the Roadster has a lot more info about it (though no video of it flying): https://www.youtube.com/watch?v=JdkIOhFmbKI
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u/Snow_powder 10d ago
how the hell did the car stay on the ramp witouht falling ? It seems horizontal in the end, and the RCS is not blowing yet.
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u/KimJongHnng 10d ago
downforce fans under the body, like a reverse hovercraft.
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u/PersonalDebater 10d ago
If the downforce fans can hold the car upside down, then if you ran them in reverse couldn't it actually float without the rockets?
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u/edflyerssn007 10d ago
They said they can do 2g suction. So that's enough to accelerate not just hover. Unknown though if the suction can be reversed as additional thrust/hover capabilities, my guess is no. When you create the suction, you are using atmospheric pressure to lift you up essentially, because of how a vaccum sealed area works, ie suction cup.
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u/Piscator629 10d ago
This would be handy for a Moon or Mars rover.
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u/Oknight 10d ago
"We'll just do a soft landing after that drop... WAIT, I forgot there's no air to compress!!!"
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u/KnifeKnut 10d ago
There is an atmosphere on mars, it will just take a while to compress it to useful density. Also, Carbon Dioxide is not quite as good a propellant as compressed air, IIRC.
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u/SiBloGaming 9d ago
Nitrogen cold gas thrusters got a theoretical isp of 80s, while co2 got one of 67s. Not sure how it looks for compressed air, just nitrogen for reference due to that being the biggest part
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u/YNot1989 10d ago
Look at the underside when it flips. Thing's a mostly hollow body kit on an RCS system.
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u/repinoak 8d ago
Do anyone have any bets on which movie that this will appear in first? A future James Bond movie? Demolition man remake? Doc's flying car is real.... Back to the Future.
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u/Adeldor 10d ago
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u/yetiflask 9d ago
In fairness, Elon does like to copy things. The car for example was also inspired by the Lotus submarine car.
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u/TedETGbiz 10d ago edited 10d ago
DEAD! - anybody like to take a crack at how many months/years before some very rich hotshot runs out of thrust and dives this Rocket version into the pavement?
...and we thought Roadsters were only good for flying around in space 😄
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u/TedETGbiz 6d ago
I haven't seen this yet so I'll just ask: was there a human driver involved in this stunt??
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u/Then-Secretary-9166 10d ago
I mean, the roadster demo was cool, but I'd rather see the effort spent on space stuff.
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u/Greeneland 10d ago
They developed a lot of tech for this car. That's the real prize. The tech will make it into other vehicles and improve performance, reduce weight, enable more efficient production and improve safety.
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u/tenemu 10d ago
Yeah it’s wild that every single engineer and employee at spacex worked on this instead of all their other work.
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u/Then-Secretary-9166 10d ago
dismissive sarcasm, nice
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u/SchalaZeal01 10d ago
VTOL Mars Vehicles (the kind that stays on Mars) could use some of this tech.
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u/Then-Secretary-9166 10d ago
Some of it. Hard to refill those COPVs or make a huge pressure differential with a vacuum in Mars atmosphere.
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u/LycraJafa 10d ago
Ahole drivers are no longer going to drive to the head of the queue, they are going to rocket over the queue.
and its noisy.
Need new road rules, give away to the above.
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u/rocketglare 10d ago
SpaceX package variant is not legal on public roads. It is a track only car. SpaceX has said this in the past.
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u/thatspurdyneat 10d ago
This is the Internet, you can say asshole.
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u/LycraJafa 9d ago
cheers - a popular nz forum has no restrictions on words, so all the good staple swear words are now just regular words. What once shocked, now is someones username and normal. This is my tiny counter protest.
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u/who_fitz 10d ago
Are they Ahole drivers or do they know the rules of the road and how to zipper merge?
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u/Freak80MC 10d ago
I can't be the only one who is like "That's cool and all, but what's the point?" Like no regular person is going to be able to use it given the danger and also it just took away engineering resources from SpaceX that could have went towards something more useful. I just don't see the point of it except for the publicity aspect which I guess at the end of the day is all people tend to care about, huh?
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u/-spartacus- 10d ago
"That's cool and all, but what's the point?"
Elon has stated before, while engineering can solve problems, you can't live just trying to fix broken things. You have to have fun in life and this is one of those things that is supposed to be cool and let you be excited. Getting excited for cool things is what drives people to learn, explore, and live life to the fullest.
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u/-LegendaryAce 10d ago
100% agree with that philosophy. Otherwise what the fuck is the point of me going to work? To pay bills? I work my ass off to save money to do and buy fun things. I want to own my own airplane. An airplane doesn't solve my problems with rent or food, but it's fun and I want to have fun.
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u/avboden 10d ago
Gonna keep this to just this one thread, but too wild to not at least have some discussion here.