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Watch a rocket-propelled katana sword slice through a drone like hot butter

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Sometimes the technology we get to cover includes astonishing breakthroughs in AI that suggest the secrets of the human brain are finally in the process of being unlocked, and that we’re soon to live in a world populated by genuine artificial intelligence. Other times we write about rocket-powered katana swords slicing drones in half.

Today is one of those “other times.”

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The creative destruction in question is the work of YouTuber David Windestal, who decided to not only build said rocket-propelled sword, but to use it to answer the age-old question: Who would win in a battle between a DJI Phantom drone and an ancient Japanese sword? Apparently the answer is We, the viewers.

“The idea behind the Rocket Knife series was to re-create the Mythbusters episode where they cut a car in half using a rocket sled,” Windestal told Digital Trends. “I thought it was so inspiring, and a very worthy challenge to create on a smaller scale. Making the rocket and sled was difficult and time consuming to get right, but very rewarding. Each episode, we ask what the community wants to see cut, and the drone was the most requested by far. The knife wasn’t tall enough, so we ramped it up to a katana sword. The hope was that the drone would be cleanly cut in half — but we failed by a literally a centimeter.”

Image used with permission by copyright holder

The rocket was calculated to burn for 0.3 seconds and have 120 pounds of thrust, which was achieved using a mixture of sorbitol and potassium nitrate. At first, Windestal said he had problems with the rocket being too powerful for the purposely lightweight sled. However, after a bit of fine-tuning, he was able to achieve his slightly terrifying goal.

“The calculated speed of the sled was within 2 percent of the calculations, and the impact energy is over 3,000 joules,” he noted. For those keeping track at home, those are drone-slicing levels of speed and power.

Which just leaves the question of why YouTubers apparently hate drones so much. There’s no definitive word on this, but we’d certainly like to know. Maybe it has something to do with a recent NASA study revealing that drones officially make the most annoying sound out of any vehicle?

Luke Dormehl
I'm a UK-based tech writer covering Cool Tech at Digital Trends. I've also written for Fast Company, Wired, the Guardian…
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