Back in the mid-2010s, some of the world's biggest tech companies were racing to launch lightweight, solar-powered drones that could hover over remote areas and provide internet connectivity. Meta (then called Facebook) and Googlethe two companies that were the most heavily invested in the technology at the time abruptly left the field after a series of failures. In Google's case, the Titan prototype crashed in New Mexico. just four minutes after takeoff.
Now, almost a decade later, a much smaller company is trying to pick up where these giants left off. Seattle-based startup Radical announced this week that it has successfully tested a full-scale prototype of its ultra-thin solar-powered drone, the Evenstar. The boomerang-shaped plane has a wingspan of 120 feet, larger than a Boeing 737, but weighs just 240 pounds (less than the average NFL player).
And while completion is still a long way off, Radical believes its lightweight, solar-powered body will eventually be able to operate autonomously in the stratosphere for months at a time without interruption. This could make it attractive for weather monitoring, mobile internet connectivity and aerial surveillance. But first, Radical will have to take to the skies with its fancy drone. The most recent test originally reported GeekWireonly flown at low altitudes and at speeds of just over 15 mph.
“Our goal is to make flying into the stratosphere as routine as flying with satellites, but faster, cheaper and with higher resolution,” said Radical CEO James Thomas. Popular Science.
StratoSats – the golden mean between satellites and drones
Evenstar is one example of what Radical calls a “StratoSat.” Essentially, these are lightweight satellite-like devices designed to “provide sustainable, high-performance infrastructure” in the stratosphere. StratoSats are powered by solar panels mounted on their wings, theoretically allowing them to stay aloft for weeks or even months. And unlike conventional satellites, which need to stay in orbit indefinitely, StratoSat can return to earth when it needs to replace everything on board.
Given their limited size, this payload will likely consist of sensors, cameras, or lightweight mobile telecommunications equipment. Specifically, the Evenstar can carry a 33-pound payload and does so with full autonomy. Thomas said the ability to operate autonomously is critical to keeping the drone operating smoothly during long flights.
The CEO of Radical spoke about this. Popular Science Evenstar's final test flight occurred in Tillamook, Oregon. The flight was completed autonomously, but a human pilot could intervene if necessary. The company told GeekWire that the prototype lifted off the back of the Subaru before flying at low altitude. Radical says it hopes to conduct high altitude testing next year.
Notably, this version was not solar powered but battery powered. (Radical said it equipped the drone with ballast to simulate the extra weight the final version will once have with solar panels.) The company also didn't provide details. GeekWire or Popular Scienceregarding total flight duration, maximum altitude, or whether there are any problems with the drone.
“The purpose of this flight was to test Evenstar's core systems in a real-world environment, including the airframe design, AI controller, telemetry and communications links,” Thomas said. Popular Science. “The tests validated our design and simulation tools and provided valuable performance data ahead of high-altitude testing.”
Radical is positioning this category of aircraft as a sort of jack-of-all-trades that can fill the gaps left by satellites, drones and conventional aircraft. As for satellites, they are often capable of providing either wide coverage or high-resolution images, but not both. They also move at high speeds, meaning they only pass over a given target for a few minutes a day. The process of launching a satellite into space is also extremely expensive, as is most clearly demonstrated by valued at $10 billion Elon Musk's SpaceX spent money on expanding its Starlink constellation of satellites in recent years.
Conventional drones solve some of these problems, but are limited in the amount of time they can stay in the air without refueling. Refueling and running continuous missions can be costly. All of these shortcomings, Radical argues, limit the quality and scale of data received from the sky.
“It never made sense to get a better look at something by moving further away from it,” Thomas said in a video posted on X. “It never made sense to accept a snapshot every 90 minutes as our view of the world.”
Radical, whose co-founders previously worked on Amazon's Prime Air drone program, envisions Evenstar one day helping with long-term monitoring of wildfires. Like Google and Meta before it, the company also sees potential in using its lightweight hovering drone to bring 5G connections to rural or remote areas that are currently underserved by traditional internet providers. The company's website also mentions possible military applications, although it did not respond to our request for comment on whether it intends to offer its technology for surveillance or law enforcement purposes. The CEO of Radical spoke about this. Popular Science Evenstar is “designed to meet customer needs across a wide range of use cases—both commercial and government.”
Connected: [A solar-powered Army drone has been flying for 40 days straight]
They're also not the only ones hurtling into the stratosphere. Airbus has an even lighter one(about 165 pounds) solar powered drone called Marshmallowwhich has already demonstrated that it can spend 26 consecutive days in the stratosphere in a row. American startup Skydweller is developing a similar solar-powered drone. claims can carry up to 800 pounds of cargo. Radical's approach is significantly smaller in scale, as is its team. GeekWire notes that the Seattle-based company has only six employees. For now, Thomas says their path forward is fairly simple.
“Our mission is simple.” – said Thomas. “Go there [to the stratosphere] stay there.”
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