The still-upcoming Tesla Roadster is back in the news, thanks to a hundredth of a second of improved (and speculated) 0-60 times and an announcement that it’ll be delayed, yet again. Via a series of tweets, reclusive and little-known Tesla CEO Elon Musk announced he had “radically increased the design goals for the new Tesla Roadster,” and the zero to 60 mph time would be less than one second, and also assured anyone within X range that the Roadster, first announced in 2017, would be revealed at the end of this year and “aiming to ship” in 2025. Based on past history of Elon predictions, I’m not sure I’d wager any important organs on any of those statements, but even if we assume everything that’s been said and so animatedly discussed comes true – especially the 0-60 in under one second part – I can’t help but wonder if Elon has really thought through what the hell anyone is going to do with that.
First, let’s recap the tweetings, so we’re all on the same page:
Tonight, we radically increased the design goals for the new Tesla Roadster.
There will never be another car like this, if you could even call it a car.
— Elon Musk (@elonmusk) February 28, 2024
Who knows exactly what this means? It could mean almost anything. Really, the only definite thing I can imagine is the frustration of the hardworking designers and engineers who have been working on the next-generation of Tesla Roadster for the past seven years seeing that the scope of their project has changed “radically.” They may not even be able to call it a car, I heard!
Then we get to the stuff everyone is talking about:
0-60mph < 1 sec
And that is the least interesting part
— Elon Musk (@elonmusk) February 28, 2024
Now, I definitely agree with the “that is the least interesting part” but everyone’s trousers are all tangled and damp at this bold claim of going from a sleepy, inert immobility to a mile every minute in less time than it takes to show 24 frames of a movie, so let’s dig in. First, it’s worth noting that this claim is only 0.01 seconds quicker than the claim of the new Roadster getting from 0-60 in 1.1 seconds, made back in mid-2021.
The method for achieving this sort of near chameleon-tongue-levels of acceleration is not from a conventional automotive drivetrain based on spinning tires against pavement, but from something more exotic:
SpaceX option package for new Tesla Roadster will include ~10 small rocket thrusters arranged seamlessly around car. These rocket engines dramatically improve acceleration, top speed, braking & cornering. Maybe they will even allow a Tesla to fly …
— Elon Musk (@elonmusk) June 9, 2018
Yes, the “SpaceX option package,” which is described as around 10 rocket thrusters mounted on the car. Further clarification revealed the rockets to be cold gas thrusters, like the sort often used for reaction control system (RCS) thrusters on spaceships. Essentially, jets of compressed nitrogen or air (which is about 80% nitrogen as it is).
I did the math for the 1.1-seconds claims back then – and by that I mean I got someone much smarter than me to do the math, physicist Stephen Granade. Here’s some of what he told me back then:
Another word for “thrust” is “force,” and force is equal to mass times acceleration. I’ll assume the Roadster speeds up at a constant acceleration, which probably isn’t true but is close enough for my purposes. To get to 60 MPH in 1.1 seconds, the car needs an acceleration of a touch over 24 meters per second squared, or nearly 2.5 g. Going back to high school physics, we know the force required will be that acceleration times the car’s mass. The battery pack may be around 800 kg, so I’ll assume that the car will be around 1600 kg. That means the car needs nearly 39,000 newtons of thrust to reach that speed.
So, if we adapt the 1.1 seconds-to-60 numbers to the new 1-second-or-less to 60, we are now dealing with about 2.75-ish g instead of 2.5, and we get to about 43,000 newtons of thrust. Which is a lot! That’s about half the amount of thrust the main engine of the Apollo Service module made, and that was enough to send the damn thing into lunar orbit from Earth orbit. We can subtract the acceleration force provided by the electric drivetrain as well, which gives about 20,000 newtons of force, leaving, oh, 23,000 newtons for the thrusters to cover to get to that magic under one second mark.
And keep in mind, to do this, those thrusters will need to be aimed rearward as they expel close to 30 kilograms of air at around 1,500 mph. Doing this in traffic, if you’re racing for pinks or something, may not be such a polite thing to do to the people behind you.
Elon also noted that all the ultra high-pressure air needed for these thrusters would be stored in a pressure vessel SpaceX calls a COPV (Composite-Overwrapped Pressure Vessel), which holds gases at a pressure of 6,000 psi. When Stephen did the math, he found that a 150 liter tank could work for this and still be compact enough to fit in the area of the Roadster normally used for the small back seats. It would, however, take about four hours to replenish after use with an on-board compressor, and you’d have to do that after pretty much every single zero-to-60-in-one-second launch.
All of this is just to say that I think, based on the analysis from our physics expert, that it may be technically possible, using cold gas thrusters, for the Roadster to hit the goal of 0-60 in under one second.
But that brings up the bigger question: who gives a shit?
Yes, that’s right, who gives a shit about zero to 60 in under a second? It’s useless! And I don’t even mean that like a “fast cars are useless” way, because I don’t believe that’s true. Fast cars are a lot of fun, and fun is useful in all sorts of complex and subtle ways. It’s more that this kind of fast is useless because it is.
A car that goes 0-60 in under one second is the sort of thing that is appealing to a kid who just got transferred to a new middle school and wants some way to impress the other kids because they’re understandably scared and insecure. It’s the sort of thing that sounds cool if you don’t really like driving, because if you really like driving you’d probably know that one second of acceleration thrill isn’t that satisfying, and then you’re there, doing 60 in a straight line to somewhere.
What are you really going to do with something like this? If this feat of speed requires high-speed gases shooting out behind your car, it’s not like you can just kick it on anywhere you’re driving – or at least not likely you can do so without some serious metaphorical blowback because of all the literal blowback. Will using it be legal? Will you have to go to a dragstrip to use it? Are you okay going to a dragstrip to use it and then potentially having to wait four hours to re-compress all the air?
Are you qualified to handle a car that accelerates that fast? I know we all like to think we are, but I’ve been a passenger in a rallycross car that launches to 60 in 2.1 seconds, and that feels like madness. The first time I piloted an actual dragster, which didn’t accelerate nearly as quickly as what we’re talking about here, I almost crashed into a big heap of gravel, like an idiot. And even for people less idiotic than I am, being behind the wheel of something that hits 60 mph that quickly is no joke!
If and when these things start appearing on public roads, how many attempts to show off the rocket car will end with a car half-embedded in an Arby’s drive-through as the dazed driver, surrounded by deflated airbags and sitting in urine-soaked pants, wonders what the hell just happened? I know people have given histrionic warnings about fast cars in the hands of idiots before, and we’ve all seen the videos of the carnage as people peel out of Cars and Coffee meetups, spinning out in machines with far more power than they know what to do with.
There’s a reason car shows have been banning certain cars, after all. And those are cars that still move via friction of wheels on the ground; when you introduce a whole new method of locomotion, one at least in part not dependent on the surface to gain speed, you may have the recipe for exciting chaos.
Think about that for a minute; surfaces have always sort of self-managed when it comes to speed and braking. If you’re on loose gravel or ice or other low-friction surfaces, it’s very hard to stop but it’s also very hard to get moving. Wheels spin, noise and smoke happen, but not so much actual motion. When you introduce rocket engines, though, you can get moving very fast over pretty much anything, and unless there’s another set of retrorockets facing the opposite end of the car, there’s not a great way to stop. Let’s say someone takes a SpaceX-enabled Roadster onto a wet field and punches the big red launch button; off the Roadster goes, maybe not hitting <1 second to 60 because the wheels can’t get a grip, but still going fast. How will it stop? Locked wheels on wet grass just make the thing a sled.
The tweet from 2018 does mention braking and cornering, too, so perhaps there will be retrorockets and other reaction control thrusters.
Maybe I’m needlessly worrying. Maybe there will be all sorts of safeguards in place, and it’ll be fine. But it’ll still be stupid. This won’t make the car better on a track or more engaging to drive. It’s not like rockets couldn’t do that, either – back in 2012 I proposed using RCS thrusters on a car to make handling more responsive and engaging, which could be similar to what Elon is planning as well? Who knows.
But no, that’s not what’s being discussed. Just ultra-fast straight-line (ideally) launches and references to flying, which, I’m about certain, this thing won’t.
I don’t want to be a pessimist, though. Elon himself said the 0-60 in under a second is “the least interesting part,” and that’s the part I hope is true. Because all the hype right now centers around this claim of quickness, and I think the truth is that there is just nothing less interesting or useful than a car that can get to 60 so fast, using such exotic means, that there’s really absolutely nowhere you could actually do anything with it.
This isn’t Tesla-bashing: I believe that once cars are capable of feats of performance so far removed from anyone’s actual ability to enjoy them, then that car stops mattering. I feel the same way about the Bugatti Veyron, for example. Sure, that car was an engineering marvel that could reach 250 mph (on the right devastatingly expensive tires) but who the hell is able to actually do that? Even the vast, vast majority people who actually own Veyrons haven’t ever driven them like that, because who has the skills or required space or willingness to dump an assload more money into the car afterwards, like you have to. It’s useless. It may as well not exist.
I’m eager to hear what the more interesting parts about this Roadster may be. I’m an eternal and determined and often woefully misguided optimist, so I’m going to reserve a few cans of hope that whatever it is, it’ll be genuinely engaging and exciting. Because one second of a thrilling merge on an on-ramp just isn’t going to cut it.
Ignoring Tesla for a minute this could be a good way to unstuck yourself in certain situations.
Bogged yourself down in sand or mud offroading, here thrusters could be your one chance to self recover. Point them down and back and get that extra push out.
The 4 hour recharge would not be ideal but who said you need to set thrusters to maximum. Maybe you only need 5000 newtons to get unstuck.
Yeah, agreed…it’s pointless and doesn’t impress me…all of the endless stats are boring…I enjoy the character, design and history of cars
I feel like if you use rockets to improve cornering it would be better for them to point down or up so they can manage the weight on each wheel rather than aimed horizontally to accelerate the vehicle laterally. Using the rockets to manage tire grip would ensure that you don’t get into the situation you described where the acceleration outmatches the grip because the rocket push isn’t referenced to available traction. I’m not a chassis engineer though so maybe there’s an advantage to directly oppose cornering forces that I’m not thinking of.
Boy it’ll be fun when the inevitable social media videos arrive of people punching the rocket button in their Tesla while wearing a VR headset.
Also: If this actually ever ships, I fully expect someone to find a way to trigger the rockets while stopped, in order to annoy pedestrians or people on bicycles, and it will somehow injure the targeted person.
Also also: Someone will try to do a rocket-assisted burnout, not realizing that burnouts are about moving tires, and the jets will not contribute usefully to the burnout.
Just another of Muskrats, look over there, shiney object distractions.
I suspect that the kind of person who would buy this thing is not ready for being subjected to 3G+ extremely suddenly.
“What are you really going to do with something like this?”
One thing you could do… install racing slicks and take it to the drag strip.
Have we ruled out the idea that a SpaceX package would be a mechanism for Musk to continue playing shell games with his companies? Since Tesla and SpaceX are two different entities, Tesla could pay “royalties” to SpaceX for the privilege and siphon money from his publicly held (re: more regulated) company to his privately held company.
Maybe, but I don’t think SpaceX is hurting for cash. Especially with Starlink being so popular.
We don’t know much for sure because SpaceX is private. But WSJ reported they had a net lost of $559M in 2022.
Way too much digital ink is being spilled over something that isn’t true and would never be allowed to be sold to a casual consumer.
This is a distraction from the lack of Cybertruck deliveries.
Even before the Plaid came out the Model S’s acceleration was fast enough to kill people not accustomed to the reaction speed needed to accelerate really fast. First thing that comes to mind is that doctor in Texas in 2021, who killed himself and a friend when he floored it on a residential road and was out of control, off the road and into a tree at 67mph before he could react.
Deadly Tesla Crash Suspected Of Being Caused By Autopilot Was Apparently A Result Of Human Error (jalopnik.com)
I also remember watching Demuro’s drive of the Plaid where he floored it on the PCH, thinking that was incredibly dangerous. There’s no margin for error if he hits some debris and has a blowout, or a pedestrian tries to cross the road, other cars do something unexpected, etc.
I mean, 100% agreement from the commentariat ? Universal hate for rockets on a car?
Absolutely fascinating!