Zuckerberg first unveiled his vision for flying wireless internet access points in March last year. The aim of Internet.org is to use solar-powered, internet-beaming aircraft flying over remote communities to connect parts of the global population that don't currently have internet access.
In a Facebook post this morning, Zuckerberg revealed that the Internet.org aircraft have been successfully tested in the UK. Indicating that it is still under development, he says the finished aircraft will have a wingspan greater than a Boeing 737, but still weigh less than a car. It will be capable of flying at an altitude of 60,000 ft (18,288 m) for months at a time.
"Aircraft like these will help connect the whole world because they can affordably serve the 10% of the world's population that live in remote communities without existing internet infrastructure," Zuckerberg writes.
And Facebook isn't the only company with high-flying internet aspirations. Last year, Portuguese company Quarkson announced its SkyOrbiter program that plans to use UAVs to transmit internet access "to every corner of the world," while Google has floated the idea of using balloons with its Project Loon and is continuing testing of the concept having just successfully sent a balloon on a 20,000 km (12,400 mi) trip from New Zealand to Australia – the long way around.