- Back in October, the
SSC Tuatara set the record for the fastest production
car in the world at 316 miles an hour. That is crazy fast for a production car, but it got me thinking, what's the top speed any car has gone? Well, it turns out it's over
double that, 763 miles an hour. And that record was set... Hold on, is that right? 23 years ago? Well, car technology has
obviously advanced it then so why hasn't anyone
beaten this record? - Well, I mean the old
textbook you can go and buy that tells you this is how you design a 1000 mile per hour car, right? - Well, that's Dr. Ben Evans. And he's part of the team
looking to break that record by building a car to
hit 850 miles an hour. And 850, that's cool and all, but you know what else is cool? 1000 miles an hour. Is that even possible? I mean, what does it take to make a car go 1000 miles an hour? Well, today we're gonna break it all down and it turns out it's
pretty, pretty complicated. So let's get into it. (upbeat music) (beep) Big thanks to Audible for
sponsoring today's episode of Bumper 2 Bumper. Now your old uncle Jerry over here has a lot of free time on his hand, and there's only so much
birdwatching I can do. I've seen literally all birds, but I heard about this thing
called the interweb book thingy and it's called Audible. I found out they had these
things called audiobooks where a voice reads me a book
through this headphone things. It's great. A voice reads to me. Okay, what the heck it's magic! And I've been listening to Greenlights by Matthew McConaughey narrated
by Matthew McConaughey. You know, I do pretty good
Matthew McConaughey impression. All right. All right. All right. Nailed it. Now Audible isn't just limited to literally thousands of audiobooks, oh no no, they have all
sorts of exclusive podcasts, theater performances and
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Audible for yourself. Head on over to audible.com/bumper2bumper or text on your little phone thing, BUMBER2BUMBER to 500-500,
you get 30 day free trial. Okay, I gotta get back to this audiobook. Take me away Matthew, take me away. I'm picturing him with
his shirt off right now. You don't know it, but he's naked. All right quick physics recap. In order for a car to accelerate, there has to be an imbalance between the force pushing it forward and the resistance trying to slow it down. As long as there's more forward force, the car will continue to
accelerate faster and faster until it's met with an
equal amount of resistance at which point it will
even out at its top speed. So to help us visualize this,
made a little Donut balance. And on this side, oh (beep). This side will represent
the forces necessary to drive the car forward. And this side represents the
forces creating resistance. Let's say this shot of
liquid equals 100 horsepower, about the same as a Mazda2. Now on a frictionless surface with zero resistance in a vacuum, you wouldn't need more than 100 horsepower to get to 1000 miles an hour. But in the real world,
that 100 horsepower, it's gotta go through a drive train which creates mechanical resistance. It's gotta overcome rolling
resistance from the tires, and it's gotta push back air resistance, pushing back on the car. Now these forces create
resistance on the car which is why 100 horsepower Mazda2 isn't breaking the sound barrier. In fact, it's barely
breaking 100 miles an hour. That's a 10th of the speed we need. So to go 10 times faster, why don't we try giving
it 10 times more power? So now we're at 1000 horsepower. 1000 horsepower 1000 miles an hour. Big bang boom we got it. Well, it turns out that
it's not that easy. An actual 1000 horsepower
car, like the Bugatti Veyron it only reaches about 250 miles an hour. And one of the main reasons
is more air resistance. The faster you go, the more it stacks up. (chuckles) Now let's actually look at the equation for determining air resistance. It includes the density of the fluid which is just our atmosphere, the velocity of the object,
that's how fast it's going, the coefficient of drag,
which is just a measurement of how well the shape of an
object can move through a fluid, and the cross-sectional area. But really the most important thing is this a little two right up here. Because the velocity is squared, it means that an increase in speed results in a quadratic
increase in air resistance. Meaning that if you double your speed, the drag force it doesn't
double, oh no, it quadruples. So we have a few ways in
which we can combat this. We can keep increasing the
power or we can reduce the drag. Well, sometimes reducing
drag isn't an option because it can be the only thing keeping the car on the ground. Passenger cars naturally have
a shape that generates lift. Look at the cross section
of an airplane wing and look at a car, they
look pretty similar. Now if we didn't do
anything to combat the lift, and then a car like a Mercedes A-Class with the lowest coefficient
of drag for production car going about 250 miles an hour
would generate enough lift to counter 98.3% of its own weight. The car would be the
equivalent of 55 pounds. Now a bump in the road or slight breeze would be enough to
knock the car off course and the steering, well,
it would be almost useless as front tires would have no traction. So to combat this, we
need to add some downforce but that downforce
inherently creates drag. So reducing drag is pretty much
out of the question for now. Our only option is to increase power. - [Man] More power baby. - So if this is equivalent
to 100 horsepower, then this is equivalent
to 10,000 horsepower about the same horsepower
that's in a top fuel dragster. And these drag racers
can hit 300 miles an hour in under four seconds. But dragsters like this only
run a quarter mile at a time. Well what if we just say, we just let one of them keep going? Could it reach our goal
of 1000 miles an hour? What do you think? No, they can't. And the easiest way to
explain why this is, is because dragsters are built
so specifically for one task that they can barely survive
just one run that they do. Their clutches, literally
they last one run during which they weld themselves
together from friction. So if we wanted a dragster to keep going, you're gonna need more
cooling, you'd need more fuel, you need a bigger transmission, you need beefier engine internals. And all of that means
you have more weight, more weight means we need more
power, which means more fuel. And to have that more power,
we need to cool all that, which means more weight. It's a snake, eating its own tail. Hmm! Yum, yum! Ah, I love my tail. Hmm my tail so good. Yum, yum, yum! And we haven't even gotten into
the mechanical limitations. So let's look at the Veyron for instance. Now forget wind resistance,
forget rolling resistance, forget parasitic losses and all that jazz. It can still only go as fast
as its engine can spend. So say we want the Veyron
to reach 500 miles an hour with its current rev limit of 6,600 RPM. We could on paper do that. And in fact, we did the math. (audience laughs) We would need the last gear ratio and the transmission to be 0.42 which would be something
around like 15th gear if we had to step it all the way up. Or we need 53 inch wheels, which would be a pretty ball away to solve this physics problem. And while that works on paper, it doesn't account for parasitic
losses, component strength and the added unsprung
weight of the wheels. Not to mention, the engine
would need way more torque to turn a system that big. Now land speed record cars have come up with a solution for all this, but it isn't more torque it's no torque. No torque. - As soon as we hit
kind of four hundred-ish that sort of region 400
miles an hour or so, that's when the switch had to happen to thrust driven vehicles. - Now, this is Dr. Ben
Evans aerodynamicist on the Bloodhound LSR
Land Speed Record Project. The current car going for the record. - And it just becomes the more natural way of propelling yourself forward once you're at these sorts of speeds. - Now what he's talking about is rocket and jet powered cars. With these there's no torque measured because nothing is turning. Instead, we have pounds of
thrust pushing us forward. How much thrust? Well, the land speed record holder from the 1970s reached 622 miles per hour using a rocket engine making
22,500 pounds of thrust which in liquid horse juice
terms is about this much. Mazda2, 1970s land speed record holder. (heavily sipping liquid) Now this is about 58,000 horsepower. Now the car was called the Blue Flame and it held the official land
speed record for 13 years, which actually brings me to the next problem in this equation. And that's the record itself. The land speed record is an
official FIA world record and to hold it, you can't
just reach the top speed, oh no, you gotta stay there. And the record is for a flying mile which means that the
speed is the average taken over a whole mile and then it's averaged against another run in
the opposite direction within the same hour. Now the Blue Flame was
like a bottle rocket, it relied on its lightweight
and bursts of thrust for its speed. Now that design only gets us so far because after 650 miles an hour, air pressure begins to increase as we enter a space called- - [Heavy Voice] The Transonic regime. - No I'm not talking
about Jared Leto's cult. Although Jared Leto hit me
up, I'll be part of your cult. - Essentially the transonic regime is as soon as there's air
flow around the vehicle is traveling faster
than the speed of sound. And that happens before the vehicle itself gets to the speed of sound. And that's when drag really starts to build up around the vehicle. - [Narrator] So basically
as an object approaches the sound barrier, the air begins to stack up
on the nose of the object like a pile of pancakes that
are harder to push through than your normal air. And once you break that sound barrier, object pokes through that
pancake and they break apart just like this analogy and
you create a sonic boom. At least that's how it works in the air. On land that sonic boom hits
the ground you're running on. - The fact that you're
giving that spray momentum, leads to a drag term and in
kind of high speed motorboats, they refer to this drag as spray drag. And it's a similar phenomenon for us. So we've termed this additional drag, which, you know normally
as an aerodynamicist you don't need to account
for, a spray drag. - So you can see why it'd be a lot harder to break the sound barrier
on land than in the sky. And it wasn't until 1997, 50 years after Chuck Yeager
broke the sound barrier in the Bell X-1 that the sound barrier was just barely broken
on land by the ThrustSSC. All the components and power needed meant that this super sleek looking plane with wheels weighed 10 tons and made the equivalent
of 100.000 horsepower. A thousand times more power
than our little Mazda2. Just to get a peeky tow
across the sound barrier for just a second and
a record speed average of 763 miles an hour. We're not even close to
hitting 1000 miles per hour. So how much more do we need to get there? Well, this is where Dr. Evans and the team building the
Bloodhound LSR come into play. Now it's the current contender
for the land speed record and it's scheduled to make its run soon in the Hakskeenpan of South Africa. Now the Hakskeenpan is
a dry lake bed so flat that you can see the
curvature of the earth. Over a 10 mile stretch,
the elevation changes by only 300 millimeters. And it's even flatter now because the Bloodhound
team removed 16,000 tons of stones by hand. Now with the equivalent
of 135,000 horsepower or 10 of these gallon jugs,
Bloodhound has already made it to 628 miles per hour in test runs. And it's gonna go a lot faster. So yes, Bloodhound in theory
could go 1000 miles an hour. It's got the thrust, it's
got the drag coefficient, it's got the crazy team behind it. But there's still some
holes in this equation that you just can't slap a Mo
Powa Babeh Sticker over it. And we've talked about
g-forces and their effect on the body in previous episodes. But the main thing you need to know is that sustained g-force
is way worse for the body than instantaneous g-force. In a crash, you might experience
8g or more for a second, but in land speed record attempt, if you wanted to maximize
your use of the space, the driver would experience sustained G from the moment of launch all the way up to the moment they pull parachute. And then there'd be more sustained G as the car decelerates to stop. - In principle, I mean the only way you can overcome that barrier of fundamentally how
much distance do you have is accelerate quicker, decelerate quicker, but then you move into the realms of what can the human body sustain, and of course, fighter jets and so on will experience G loading
of much higher than 3g, but that's for a relatively
short amount of time. - So Bloodhound might be accelerating as fast as a car can safely accelerate, and if it doesn't have the
space to reach its top speed, they've gotta find a new spot. Literally the land speed record
is determined by the earth. That's the limiting factor. The initial goal when we
set out on all of this over a decade ago, the design brief was what does a 1000 mile
per hour car look like? You know, we still don't know in reality if that is possible, but we believe in principle
Bloodhound has the potential to go at that sort of speed. - But will it? I mean, I don't know, I don't think so. I'm sure that the Bloodhound team they're gonna get close to it. I really hope they do. Big thanks to Dr. Ben Evans for taking the time to speak with us. Maybe we'll put up an
extended cut of that interview for all of our Donut
Underground followers. By the way if you're interested in where we got our liquid horse juice, I followed a horse around for a long time. Until next week. Bye for now. (upbeat music)
