Everyday

- hi it's me, tim doddthe everyday astronaut. elon musk is again talking about combiningtwo of his companies, spacex and tesla, in a pretty epic way. instead of putting a tesla into space, this time they're talking about putting spacex's rocket thrusters on their next generation tesla roadster. what?

okay, please, please,please tell me this is true! elon's been tweeting up a storm, and claims that by addingaround 10 small rocket thrusters they can dramaticallyimprove acceleration, top speed, braking andcornering. (chuckles) but can this actually be true? how big of thrusters will a car need to actually make asubstantial improvement? surely we're not looking at them

putting a merlin engine on a car, right? i mean that definitely goes against tesla's green initiatives. well we're gonna take apretty deep dive today, including what concerns wehave about a car with thrusters driving around on the streets? are we all at risk of ourshin hairs being fried off on any random street corner? or what about our carsgetting blown off the road

every time a tesla roadster flies by? well we're gonna look atsome other technologies that are similar, look atthe actual cold gas thrusters spacex uses for their falcon nine rockets, and take a look at someexamples in spaceflight history that include using thrusters to increase the downforce of spacecraft. then we're going to calculate just how much faster

the zero to 60 could beon the tesla roadster if we add some reasonablysized thrusters on it. to me, this is the ultimate definition of everyday astronaut. an everyday thing like acar, with rocket technology! hey, i mean come on, there's a reason i named thatcommercial i made for tesla space ships for earth. yes, another opportunity to talk about

both teslas and rocket science. i couldn't be more excited. let's get started! - [announcer] three, two,one, zero and lift off! - [neil] that's one small step for a man. (upbeat, electrorock music) - on november 16th, 2017, elon musk showed the worldhis new electric semi. but then out of nowhere, he shocked us all

by showing off the secondgeneration tesla roadster. (laughs)this car is bonkers! zero to 60 miles an hour in arecord shattering 1.9 seconds, over 250 mile an hour top speed and an all electric range of almost 1000 kilometers or 620 miles. the car is already quantifiably insane. then, a few days later,elon dropped a small hint about the plans for the roadster.

he tweeted this: "not saying the next genroadster special upgrade package "will definitely enable itto fly short hops, but maybe. "certainly possible. "just a question of safety. "rocket tech applied to a car "opens up revolutionary possibilities." okay, yeah, sure elon. rocket technology on a car.

but then we started to actually hear more about this specialaddition spacex package. so when elon tweeted on june 9th, 2018: "spacex option packagefor new tesla roadster "will include around 10small rocket thrusters "arranged seamlessly around the car. "these rocket enginesdramatically improve acceleration, "top speed, braking & cornering. "maybe they will evenallow a tesla to fly."

whoa!(chuckles) he really doubled downon this whole thing. so what the heck couldhe be talking about? well then we ended uplearning a decent amount more on a follow up tweet: "using the config you describe, "plus an electric pumpto replenish air in copv, "when car power draw dropsbelow max pack power output, "makes sense.

"but we're gonna go a lot further." so it seems like using something similar to the cold gas thrustersoff the falcon nine would be a good fit. so let's take a look at those. at the top of the first stageof the falcon nine rocket there are two packs of cold gas thrusters, otherwise known as nitrogen thrusters. spacex uses these nitrogen thrusters

to re-orient the first stage after it lets go of the second stage. they do an initial 180 degree flip, so that the booster caneither do a boost back burn and head back to land, or so it can continueon it's parabolic arc and reenter, engine first. meanwhile, the nitrogenthrusters continue to home in on their landing target

while the booster isout of the atmosphere. each pack of nitrogen thrustershas four nozzles on them so between the two thruster packs, they can pitch, yaw or roll the booster. these run purely offhighly compressed nitrogen, which shoot out thenozzle and provide thrust. the compressed air comes out really cold due to the laws of thermodynamics, hence cold gas thruster.

so this is good news when itcomes to being on a street car. the thrusters don't burn any propellants or have any kind of chemical reaction. so at least our shinhairs won't get burnt off every time one drives by, butthey might get a little cold. but i don't think they'regoing to be street legal. i can imagine bursts of air ripping off other people's fenders, or knocking over children or something,

not to mention the noise. it might only be usedin emergency situations or off-road use, and that's how elon seesit happening as well. but a lot of this depends onhow powerful they are, right? we can get a rough calculation on how powerful the firststage's nitrogen thrusters are based on how quickly the first stage rotates around its center of mass

and knowing the approximateweight of it at that moment. which has led to speculationof these nitrogen thrusters being around 1000 to2000 pounds of thrust. okay, so i don't think they're going to be anywhere near thatpowerful on the roadster, but at least we know what kind of thrusterthey're going to use. so how are they actuallygoing to work on the roadster? well, we don't actually have to go too far

to see real-life applications of this. as a matter of fact, boschis working on a system to help keep motorcycles safe when their tires exceedthe limits of grip. these compact thrusters for motorcycles are only one time use, like an airbag, but they show how a thruster can fire if a motorcycle eitherexceeds their lean limit or hits gravel or sand.

and this is how i seethis system being used. with around 10 thrustersmounted on the roadster, the computer could sense when the vehicle reaches its limit of grip and either fire a thrusterupward to increase the downforce, or perhaps when stoppingor changing direction, it would fire in the opposite direction. so we know that firing a thruster could actually give momentary bursts

either to aid in change of velocity, or increase the downforce of the car, which would increasethe grip on the tires. but here's the cool thing. we've actually seen spacecraft use thrusters to increasethe vehicle's grip in a low gravity environment before. on november 12, 2014, the european space agency's philae lander

made contact with comet 67p. due to the comets insanely low gravity of only 1/10000th the amount gravity we have here on the earth, the lander was supposed to fire a thruster pushing itself into thecomet once it landed so it could secure itself with harpoons. unfortunately the thruster didn't fire and the philae spacecraftbounced and bounced and bounced,

eventually landing in ashadowy region of the comet and going into a permanent hibernation. dang it. okay cool, but how wouldthis actually work. well elon went on to tweet about how they'd basically take ahigh powered electric air pump and compress air into a copv, or composite overwrapped pressure vessel, that spacex uses tohold high pressure gases

like nitrogen, tea/teb, andhelium in their rockets. so the air pump could drawpower from the power pack whenever there's spare power to be had, which is apparently most of the time. not to mention, when an electric car isregeneratively braking, it can often overwhelm therecharge rate of the battery pack and have to revert totraditional brake pads. so in times like these, someof that additional power

could be sent off to thepump to compress air. so really, there is definitelythe capacity to compress air and have an additionalpower boost, literally. so lastly, let's talkabout the performance we could expect to see from such a system. okay, i don't wanna speculate too much on lateral grip or braking distances, but what i do wanna talkabout is acceleration. with a zero to 60 timeof just 1.9 seconds,

most people agree that the tesla has literally hit the absolute limits of what's physically possiblewith street tires on a car. there simply is not enoughgrip to go any faster. but luckily, thrusters wouldn'tutilize the tires' grip, they would act externally on the car. any force introduced by the thrusters pushes the mass of the vehiclewithout using the tires. and this is a good thing.

so here's some of those numbers. if elon claims the carcould fly, or at least hop, it would need a higher thana 1:1 thrust to weight ratio. so let's just make up some numbers here, let's say the car will be about 1350 kilograms or 3000 pounds. that means we'd need at least 1350 kilogramsor 3000 pounds of thrust in order to hover.

so let's pretend each thruster has around 300 pounds ofthrust, which is a lot, it would need all 10thrusters pointing downward in order to make it capableof hovering, let alone flying. but it's probably safe to assume we don't want all thethrusters pointing downwards, that would decrease the grip. we want to add downforce,or lateral force to the car. so let's pretend half of the thrusters

are on the back of thecar to push it forward. how quickly do you thinkwe can get zero to 60? so we now we'd have about1500 pounds of force pushing the car forward, we'daccelerate at about .5 g's. the stock roadster canaccelerate at about 1.44 g's to reach its zero to 60 of 1.9 seconds. so if we add these twotogether, which we can do since the thrusters wouldn'tchange the grip on the tires, we come up with a theoretical zero to 60

of just 1.41 seconds. oh my god! and now just for fun, what would it take to get that car down to belowa one second zero to 60? well it would require2.76 g's of acceleration to get a .99 second zero to 60. this means the thrustershave to push the car an additional 1.32 g's morethan the motors and tires can, so that would require3960 pounds of force.

i really can't imagine aworld where this will happen, but oh my god, i want that so bad! okay, now of course iliterally made up numbers for thrust and weight here, but based on the numbers of the real falcon nine'snitrogen thrusters, it's safe to think there'ssome real potential here. based on some roughestimates, it would require somewhere between a 13gallon to a 30 gallon tank

in order to hold enough compressed air to have any significant usage. but luckily that does coincide with elon's reply to me on twitter asking how big the copvs would need to be in order to have a substantialimpact on performance. his response would be that they replace theback seats of the roadster with the copv tanks.

so that sounds about right. so hold on, this is all actuallykind of coming together. there is some serious possibility here. i can't believe it. but wait, i should totally believe it. i mean after all, i have played around with fire extinguisher powered hovercraft with my friend amy shiratietel from vintage space on my facebook watch show, spacing out!

that was a ton of fun. so are we about to reachnew limits with cars? we have super cars. we have hypercars. is this the start of a new generation of super-ultra-hyper cars? maybe, and i couldn't be more excited. so what do you think? do you think elon's justblowin' a bunch of hot air?

(chuckles)or should i say cold air? i personally really think this is actually going to be happening, and he tends to not joke around with too much with stuff like this. he really loves makingthe ludicrous happen. so let me know your thoughtsin the comments below. i owe a huge thanks tomy patreon supporters for helping make this

and other everydayastronaut content possible. i owe a super specialthanks to those patreons in our exclusive discord channel, and our exclusive subreddit, for helping me script and research. if you wanna help contribute, please visitpatreon.com/everydayastronaut, thank you. i also owe a special thanks to whereisroadster ontwitter, and jonny hyman

for helping double checking my math. i'd hope we got it kind of right. don't forget to check out my web store for shirts, hats, mugs,prints of rocket launches, and other original artwork, and lots of other fun stuffat everydayastronaut.com/shop. as always, all the musicin my videos is original. feel free to check it out for free at soundcloud.com/everydayastronaut.

tell a friend. thanks everybody, that'sgonna do it for me. i'm tim dodd, the everyday astronaut, bringing space down toearth for everyday people. ("jovian moon run" by everyday astronaut)

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