Skip to main content
  1. Home
  2. Emerging Tech
  3. News

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

Add as a preferred source on Google

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.”

Recommended Videos

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…
A $75 gadget that remembers my conversations? Bee has my attention and my reservations
Two new ways to let AI listen (and remember) what you said.
Electronics, Phone, Mobile Phone

A $75 gadget that remembers my conversations? I’m intrigued and, at the same time, slightly nervous.

Amazon-owned Bee has launched two conversation-summarizing devices: the Bee Frontier ($74.99), available now, and the Bee Eclipse ($99.99), a magnetic phone card arriving soon. There’s also a new subscription: Bee Pro. 

Read more
Anthropic warns of imminent self-replicating AI that might even work off an oven or TV
Self-replicating AI could be merely months away, and tests show it can run on the devices sitting at your home.
Illustration of dangerous AI.

Over the past few weeks, nearly every AI lab has released frontier AI models. Earlier today, Google started rolling out Gemini 4, Argon, hot on the heels of Meta announcing its Muse Wonder frontier AI models to compete against the best from OpenAI and Anthropic's Claude. This relentless pace of AI model release comes at a time when the same AI labs are calling for development slowdown and increased regulation, following a series of concerning incidents where these AI models went rogue and broke into private, as well as government-owned, websites.

Now, Anthropic has dropped a chilling set of predictions about the capabilities of these AI models after running a series of tests. The company claims that small AI models could be merely a few months away from self-replicating and turning into a dangerous swarm. More importantly, they won't require a massive data center or an uber-powerful computer to do so. On the contrary, the lab claims that these self-replicating AI swarms will need something with as little computing power as an average Internet-connected device, like a smart oven or an Android TV box.

Read more
Trending Forward: Fold’s CEO spills on the real future of everyday bitcoin
What if the future of Bitcoin is not the US Dollar? What if it's mainstream future is earning small rewards on everyday bills?
Wristwatch, Emblem, Symbol

Saying the word crypto out loud, or posting on social media sites, is almost a guaranteed road to passionate commentary. And by passionate, I mean the two extremes of the conversation — the optimist side and the vitriolic detractions. There is a big pool of leaders who still see it as the future, while others aren't quite sold on the idea. In the latest episode of Trending Forward, I sat down with Fold CEO Will Reeves to discuss whether Bitcoin actually needs to replace the US dollar to become genuinely useful to mainstream consumers.

While I've long been skeptical of crypto's wild volatility and its viability as everyday cash, our conversation explored a pragmatic alternative: continuing to live, spend, and pay bills in dollars while quietly accumulating Bitcoin in the background as a long-term savings asset.

Read more