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Facebook has announced that it has completed the first flight of its UK-developed solar-powered, high-altitude drone aircraft designed to provide internet connectivity to remote regions.

The ‘Aquila’ drone was developed over the past two years by the company’s UK-based aerospace unit and will boost the Internet.org project set up in partnership with other tech firms in 2013 to widen global internet connection.

Internet.org aims to benefit the estimated more than four billion people who are not yet online, and has already connected more than 1 billion people by working with mobile operators. But Aquila will help reach the 10% of the world’s population living in remote locations where technologies used everywhere else are not feasible.

Facebook plans to build a fleet of Aquila drones to fly in 3.6 mile-diameter circles at 6 0,000 to 90,000 ft to avoid other air traffic and at an estimated 80mph to provide internet coverage for an area 60 miles in diameter. The drones will stay in contact with each other and the ground using lasers and will remain airborne for months at a time.

Aquila’s laser communication technology was developed by Facebook’s Connectivity Lab’s communications team in the US and will be used to deliver data at tens of Gbps, roughly 10 times faster than the previous technology, according to Facebook.

The Aquila was developed in the UK with the help of expertise acquired through Facebook’s purchase of UK aerospace five-member start-up Ascenta, led by chief engineer Andrew Cox, in 2014 for £12.5m. The drone was tested in Yuma in the US state of Arizona.

The test flight was scheduled to last 30 minutes, but was extended to 96 minutes to gather as much data as possible. It marks the start of what is expected to be a year of test flights.

Facebook founder and CEO Mark Zuckerberg said while the test flight was a milestone, there was still a lot of work to do to solve “some difficult engineering challenges”.

Although the Aquila has a wingspan wider than a Boeing 737’s, it has a mass of less than 500kg thanks to its carbon-fibre frame. But, according to Zuckerberg, development teams are working to find ways of making the aircraft even lighter.

Almost half the drone’s mass comes from the aircraft’s batteries, a lot of weight to put on large, flexible wings, he said.

“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,” Zuckerberg wrote in a blog post.

The Aquila has to collect enough energy from the sun during daylight to keep its propellers, communications payload, avionics, heaters and light systems running when it is 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,” said Zuckerberg.

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,” said Zuckerberg.

Aquila is mostly self-sufficient, but according to Zuckerberg still relies on a ground crew of about a dozen engineers, pilots and technicians who direct, maintain and monitor the aircraft. They control it through software that lets them determine heading, altitude and airspeed or send Aquila on a GPS-based route.

“Take-off and landing are automatic, since no human pilot can land in a precise location as well as software can,” he said.

The first test flight did not end with a textbook landing, however. The fragile structure was damaged when it landed in a stony field short of the runway, according to the BBC.

Zuckerberg has acknowledged the firm will benefit in the long run if more people gain internet access, but claims the project is based on the conviction that internet service can bring economic and social benefits to developing nations.

In parallel to work by the Facebook-led Internet.org, Google is experimenting with high-altitude balloons as well as drones and satellites, while Microsoft has funded a project to transmit internet signals over unused TV frequencies.

– Warwick Ashford