Facebook is preparing to fly drones above its headquarters in Menlo Park, Calif.

The tech giant recently requested a “special temporary authority” from the Federal Communications Commission, the government agency that handles radio spectrum licensing, to broadcast wireless networking waves at a frequency of 27.95 to 28.05 gigahertz in the surrounding area. The reason? To test telecom tech via unmanned aerial vehicles in the air over its offices between this month and April 1st of next year.

Aside from a sparse set of technical specifications, the company released few details about the short-term trial in its public filings, first spotted by Business Insider.

“The purpose of this operation is to test potential new communications applications and equipment in a controlled, low-altitude airborne environment,” the company’s drone division, FCL Tech, wrote in an FCC application, citing Mark Johnson, Facebook’s deputy general counsel, as a point of contact.

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Many of the particulars, such as the maker of the “transmitter unit,” are either not listed or marked as “confidential.” What we do know is that Facebook fb requested to fly an experimental “mobile station,” in this case a small aircraft mounted with an antenna at an altitude as high as 400 feet within a 5-kilometer radius of a point right outside its main campus.

A Facebook spokesperson declined to comment on the record about the program.

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“Disclosure of this information would disadvantage FCL’s competitiveness with regard to its communications services,” the company explained in an earlier note to the FCC requesting privacy on certain items, such as the “vendors of its equipment” and other “information about its test plan.” A document lists Ray Blasing, a program manager at Facebook’s Connectivity Lab, a unit that explores networking tech, as its “stop buzzer contact,” or person who can pull the plug if ordered to do so.

Here are the boundaries of the test drone’s proposed flight area.


The project appears to be unrelated to “Aquila,” the company’s Boeing 747-sized, solar-powered, Internet-beaming drone behemoth ba . Facebook has been testing that aircraft in Arizona with the intention of using it to distribute affordable wireless connectivity around the globe as part of its ambitious Internet.org partnership.

Facebook fb has been duking it out with other tech firms, like Google goog , to provide the Internet access for the far reaches of the world, a move that could land them large swaths of untapped customers for their products.