The project, based in Somerset, aimed to provide Internet basestations that could stay in the air for weeks at a time at an altitude of 60,000 ft. However the 2kW power requirements and the laser communications technology that was intended to link aircraft in the sky and to the ground were both significant challenges.
“The only spectrum available for these platforms wasn’t suitable for broadband due to technical and geographical limitations,” said Yael Maguire, director of engineering at Facebook. “We’ve made important progress on some of the other key parts of the system — including setting new records using millimeter-wave technology in air-to-ground and point-to-point communication. And then we more than doubled our record with 40 Gbps connectivity simultaneously in both directions from a ground location to a circling Cessna aircraft over 7 kilometers away.”
“Given these developments, we’ve decided not to design or build our own aircraft any longer and to close our facility in Bridgwater [Somerset]," he said. Around 16 people work there and showed the first flight of the full sized system in 2016. "Going forward, we’ll continue to work with partners like Airbus on connectivity generally, and on the other technologies needed to make this system work, like flight control computers and high-density batteries.”
The technology for the 42m wingspan craft came from the $20m acquisition of consultancy Ascenta in 2014, which was part of the design team of the Zephyr high altitude long endurance (HALE) system. That system is now made by Airbus, with the production model Zephyr S having a wingspan of 25m and weighing less than 75kg. A larger version Zephyr T is currently in development with a wingspan of 33m and weighs 140kg and will be able to carry larger payloads than the Zephyr S. It is also working with Williams Advanced Engineering on new power management and battery systems.
Around the same time as the Ascenta deal, Google also bought a HALE startup called Titan Aerospace but cancelled that