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For the Geeks: The Mechanics of Ziplining

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Ziplining is a high-flying, fun-filled, adrenaline ride that will leave your heart pumping out of your chest; this we know. What many people might not know is how some rope, pulleys, and simple physics can be turned into a mind-blowing activity. Lucky for you, we have a great understanding of how such ordinary elements can be combined to provide so much fun. So if you’ve ever wondered how exactly these unremarkable-seeming items enable flight among the treetops, read on.

Fun with Physics

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It’s all fun and games until…TREE!

First and foremost, there’s gravity; perhaps you know of it. Apparently, some guy named Newton got hit in the head with an apple and gravity was born. We might have some bad information. Regardless, it’s what makes this whole zipline thing go. We start with two points, one higher than the other, and some rope. String the rope up between these two points and you’re in business, right? Not quite. Ever heard of friction, aka the leading cause of rope burn? OK, so get some gloves, problem solved. You’re getting closer, but what about braking at high speeds, or if you lose your grip?

This is where ziplining gets mechanical. Back in the day, someone came up with the idea of a grooved wheel, known as a sheave. In the beginning, these sheaves moved like ski-lift lines, creakily and certainly not designed for speed. Today we have stainless steel, double-sheave encased trolleys, putting one of these on your rope is like turbocharging your car. By improving the sheaves, zipliners have been able to reach much higher velocities, up to 40 MPH on some of our lines! Yet in the early days, brakes were still eerily absent. The solution then was to create a gradual rise at the end of the line, which would—hopefully—slow down said kamikaze rider naturally.

A Safe New World

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This looks much safer

Thankfully, the technology has improved drastically and we no longer have to hold our breath watching zipliners trust physics to stop them before the inevitable meeting with a tree. Automatic brakes have become so sophisticated that there are brakes that use a magnetic current to bring riders to a slow halt. A more common, yet equally safe, brake type is the bungee brake. The bungee brake is essentially a large block attached to the zipline, which is attached a bungee, which is then anchored to a to a fixed point. Once the rider hits the block, momentum is slowed until the bungee stretches and slowly brings the rider back.

Ziplining has recently seen a huge uptick in popularity. This is mostly due to improvements in technology, but also to zipline course designs. At one time it was enough to just fly but those days are gone. All of our zipline courses immerse you in the beauty of Hawaii while soaring through the tropical treetops.