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  • This is Kingda Ka,

  • the tallest roller coaster in the world.

  • At 139 meters, it's nearly the height

  • of the Great Pyramid of Giza.

  • But what if we built a roller coaster even taller?

  • What if there was a coaster that went as high

  • as the tallest building on Earth, the Burj Khalifa?

  • Well, it's a good thing we don't,

  • because strapping into a ride like that

  • might be the last thing you ever did.

  • The true limit of a roller coaster's height has

  • less to do with engineering and more to do

  • with the limits of the human body.

  • Because the higher the roller coaster,

  • the faster you'll drop under gravity.

  • And on our 800-meter-tall megacoaster, riders would hit

  • the blistering top speed of 370 kilometers per hour.

  • Going this fast, the wind alone would cause serious damage.

  • For comparison, here's what a wind tunnel

  • does to a human face.

  • Matt Calabrese: Your skin would pull back at the cheeks,

  • your eyes would be seeing a lot of damage

  • if there was debris in the air or anything like that,

  • and your ears would probably start popping,

  • which wouldn't be fun.

  • Narrator: Some of this is already a problem

  • for Formula Rossa, the fastest roller coaster in the world.

  • It reaches a top speed of 240 kilometers per hour.

  • And anyone who rides it has to wear goggles

  • to protect their eyes.

  • Because at those speeds, dust and debris

  • in the air turn into tiny missiles.

  • Speaking of missiles, dust and debris

  • wouldn't be the only problem.

  • Calabrese: The main thing I'd be worried about is

  • if you had a bird strike.

  • Narrator: Yes, a bird strike.

  • It's rare, but it can happen.

  • Shane Matus: I was like, oh, my God, oh, my God.

  • Narrator: At lower speeds, it could leave you

  • with a bad bruise or a painful welt,

  • like with the Kingda Ka rider.

  • But at 370 kilometers per hour,

  • you, and the unfortunate bird, would likely die

  • from the collision.

  • Now, you could just wear a motorcycle helmet

  • and protective clothing before strapping in.

  • But there's another problem that no amount

  • of protective gear could fix:

  • g-force.

  • It's the force that makes you feel heavier than normal,

  • like when you're riding through a coaster loop.

  • Normally, you experience 1 g-force.

  • But when you rapidly accelerate,

  • like when you're going through a coaster loop,

  • the g-force ramps up,

  • which causes blood to rush away from your head

  • and often makes riders feel light-headed.

  • For this reason, most roller coasters don't subject you

  • to more than 5 gs, tops.

  • But we're not talking about your typical coaster.

  • If you enter a loop on the Khalifa coaster

  • at more than 300 kilometers per hour,

  • Calabrese: Blood will start to move away from your head

  • and to the rest of your body,

  • and that means you'll start to gray out

  • and then possibly black out,

  • and that's not good.

  • Narrator: So what can engineers do to protect riders

  • as they continue to build taller, faster coasters?

  • The boring option is to slow down the ride

  • by adding breaks along the first drop.

  • But there's a better, more exciting way

  • around the problem: loops.

  • Really big loops.

  • Calabrese: All we have to do is

  • manipulate the curvature

  • to maintain the g-forces that we want.

  • So, instead of a tight loop that you would see

  • on a low-speed roller coaster,

  • you need big, swooping loops

  • and large-radius curvature to make sure

  • that you're not generating huge amounts of

  • g-force at that speed.

  • And as you go through the roller coaster

  • and you lose speed due to air resistance

  • and drag on the wheels, your speed drops

  • and your curvature will get tighter.

  • Narrator: That's why many roller coasters start

  • with one big loop followed by a series

  • of faster, lighter ones.

  • So, in theory, our Khalifa coaster is rideable,

  • as long as we add big enough loops

  • and hand out protective eye gear.

  • That said, we'll probably never see a roller coaster

  • get much taller than they are today.

  • Because, nowadays, there are cheaper and more efficient ways

  • to thrill and terrify riders.

  • For example, hydraulic or magnetic launching systems

  • accelerate riders to extreme speeds without needing

  • to build an expensive, giant drop.

  • So, perhaps the only reason to ever build something

  • like a Khalifa coaster would be for the view.

  • Calabrese: I love roller coasters with beautiful views,

  • and it adds so much to the experience,

  • having a view on the way up.

  • So, any beautiful location,

  • I'd love to see a roller coaster in order

  • to get a different perspective on those views.

This is Kingda Ka,

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What If You Built A Coaster As Tall As The World's Tallest Building?

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    Vvn Chen posted on 2019/07/05
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