Fcl Tech, Inc., which also operates under the name Facebook Connectivity Lab, is secretly testing experimental wireless devices — mounted onto an unmanned aerial vehicle (UAV), i.e. drones, above the skies of the New Mexican desert, according to the latest Federal Communications Commission (FCC) Application for Special Temporary Authority.

Business Insider highlights the FCC filing, which show that FCL Tech Inc. — a Facebook subsidiary that develops aerospace and communication technologies, including high-altitude long-endurance drones aimed at providing internet access in the emerging growth world — was recently cleared by the Federal Government to conduct three months of tests from March 01 to June 01.

According to the filing, the tests are for an “LTE-based connectivity project requires a hardware prototype testing facility to assess key risks associated with communication system architecture, channel modeling and link budget verification at a coverage area spanning 50 km radius.”

While the manufacture of the drone is “confidential,” the filing indicates Fcl Tech, Inc. will be experimenting with “two units.” The filing further reveals the company is conducting experiments in the town of Truth or Consequences, New Mexico.

While the details of the project are confidential, the filing notes that the experiment will include the 3650 – 3700 Mhz radio frequency, which Business Insider notes are the “spectrum for the so-called Citizens Radio Broadband Service, an unlicensed radio band that many companies believe could be useful for 4G LTE wireless networks.”

Down the street from the Fcl Tech, Inc.’s test site, is an FAA-licensed space center located on 18,000 acres of State Trust Land in the Jornada del Muerto desert basin in New Mexico, residing next to the U.S. Army’s White Sands Missile Range. Business Insider specifies that the area is home to the space tourism industry, including Virgin Galactic. In recent years, Google has conducted experimental test runs at Spaceport, for aircraft hovering 25,000 feet in the air while operating wireless communications devices.

The suspected drone behind Fcl Tech, Inc.’s experiment could be the solar-powered “Aquila” drone. Back in 2016, Mark Zuckerberg wrote a blog post about the “first successful flight of Aquila.”

“On June 28th, we completed the first successful flight of Aquila — our solar-powered plane that will beam internet to remote parts of the world and eventually break the record for longest unmanned aircraft flight.”

The Facebook CEO describes what happened during the first experimental flight test:

“The flight took place before dawn in Yuma, Arizona. Our original mission was to fly Aquila for 30 minutes, but things went so well that we decided to keep the plane up for 96 minutes. We gathered lots of data about our models and the aircraft structure — and after two years of development, it was emotional to see Aquila actually get off the ground. But as big as this milestone is, we still have a lot of work to do. Eventually, our goal is to have a fleet of Aquilas flying together at 60,000 feet, communicating with each other with lasers and staying aloft for months at a time — something that’s never been done before.”

Zuckerberg’s breaks down the inner workings of the “Aquila” drone:

“Weight — Aquila has a wingspan wider than a Boeing 737, but has to weigh as little as possible to stay up for as long as possible. That’s why the body of the plane is made of a carbon fiber composite so the whole thing weighs less than 1,000 pounds — or about the same as a grand piano. We need to continue to make it lighter. Power — The amount of energy Aquila collects from the sun during the day has to be enough to keep its propellers, communications payload, avionics, heaters and light systems running when it’s dark. That means using about 5,000W of power at cruising altitude, or about as much as three hairdryers. We’re always looking for ways to trim this down and make our systems more efficient. Control — Aquila is mostly self-sufficient, but it still relies on a ground crew of about a dozen engineers, pilots and technicians who direct, maintain and monitor the aircraft. They control the aircraft through software which allows them to determine heading, altitude and airspeed — or send Aquila on a GPS-based route. Takeoff and landing are automatic, since no human pilot can land in a precise location as well as software can. Speed — When you see Aquila fly, one of the most surprising things is how slow it goes. That’s on purpose. In order to use the least amount of energy, Aquila needs to go as slow as possible. At higher altitudes, where the air is thinner, we’ll be able to go a bit faster — about 80 mph. Altitude — In order to take off, fly and land, Aquila’s wings and propellers have to be able to operate both in high, cold altitudes and lower, warmer altitudes where the air can be 10 times denser. We’re working to figure out how much power that takes — and what impact it will have on solar panel performance, battery size, latitude range and seasonal performance. Load — Almost half the mass of Aquila will come from high-energy batteries. That’s a lot of weight to put on large, flexible wings, which is why we have computer models to predict how Aquila’s shape deforms under load. A few more flights will help us better understand the actual in-flight dynamics. Communications — Aquila will carry a communications payload that will use lasers to transfer data more than 10 times faster than existing systems. It will be able to aim its beams precisely enough to hit a dime more than 11 miles away while in motion.”

Business Insider spoke with Steven Crowley, a consulting wireless engineer, who speculated that Fcl Tech, Inc.’s latest experiment could be related to signal strength testing of the data communication systems on the drone, and he adds that New Mexico’s environment provides the ideal conditions for it.

“From the phrase ‘channel modeling and link budget verification’ my best guess, and that’s all that it is, is that this is en experiment of signal propagation,” consulting wireless engineer Steven Crowley wrote in an email.

“Monitoring the signal strength between the two points and seeing how it varies with weather and terrain. Then change the two points and test again. The channel model and link budget would be used to predict the signal strength and, depending on the results, they might go back and adjust the channel model and link budget to make it more accurate.” He added: “They could test in Menlo Park, but it is a different, more congested environment. The area around Truth or Consequences is relatively flat and much less urban. They might have a reason for wanting to know the propagation conditions there as precisely as possible — by actually testing there and not trying to extrapolate from elsewhere. “Just speculating, I can imagine fixed communications equipment spaced at intervals to control and monitor drone flights. You’d want those links to be highly reliable. Painstaking testing can help ensure that. “Then again, I’d think you could just boost the power some on the ground and on the drone. Power can make up for lack of knowledge of, and help overcome variations in, the channel. I expect there is not much there they can interfere with. So it’s still somewhat of a mystery.”

While Zuckerberg may be on the cusp of something big – or something entirely sinister - following the Cambridge Analytica scandal, one should be concerned as nobody is in the big data collection game to the same extent as Facebook.