The following are excepts from The Atlantic Monthly article Can We Trust Google With the Stratosphere?
Google’s balloons’ primary mission might be to deliver Internet service, but it’s their aviation technology that is the real innovation. These balloons operate in the stratosphere, 12 miles up. Unlike unmanned weather balloons, they are capable of staying afloat for months, maybe years at a time. Each Loon balloon is about 50 feet wide and 40 feet high, relying solely on helium for lift. The envelope, or “balloon” part of the balloon, is one-tenth of an inch thick polyethylene fabric, lightweight and relatively delicate, but strong enough to withstand the high pressure differential of great altitudes. Google’s super-pressure balloons each have dual automatic air vents, which a remote pilot at Google Mission Control uses to control altitude by adjusting outside air levels. Tracking their every move by GPS, Google Mission Control says they can not only make them hover to a certain extent, but effectively navigate the Loons around the globe for weeks on end.
Each Loon balloon has three radio frequency antennas (on 2.4 Ghz and 5.8 Ghz bands) and a ground-pointing WiFi antenna, which beams an Internet signal to Earth in a 12-mile radius.
Google’s Loon balloons can talk to each other, and control themselves.”We use a distributed mesh network, so each balloon is pretty autonomous and has pretty much the same hardware in it,” Sameera Ponda, a lead aerospace engineer at the Dos Palos site that day, said on the video stream. “As one balloon floats over a certain area that balloon is talking to the ground antennas, and as that balloon floats away, another balloon comes in and takes its place, so it’s a pretty seamless operation.”
The extreme height at which Google’s Loons can flexibly operate raises a lot of questions. Where will they go? To what jurisdictions are they subject? Who regulates the stratosphere? Are they subject to physical intervention? And what will it mean for the world when Google breaks precedent, and achieves a stable stratospheric communications platform where everyone else has failed?
It’s crucial to figure out who controls the open space where Google’s Loons fly, and this is more difficult than it would seem. In the U.S., there are four classes of controlled airspace. According to the Code of Federal Regulations, Classes B, C, D, and E are below 10,000 feet, and designed to control lower traffic around airports. Class A covers airspace between 18,000 feet and where flight level begins to max out, around 60,000 feet (roughly 12 miles). Above that is the stratosphere, where Earth’s atmosphere gradually dissipates into outer space and the Loon balloons will fly in droves. Though there’s no point where space “begins,” the Kármán Line (327,360 ft.) has typically served that marker. Between where planes can fly and the Kármán Line, though, there’s almost 19 miles of unregulated stratosphere. Though there’s been debate, the stratosphere is generally considered sovereign airspace, but for most countries, it is un-policeable. Not only legally, but physically; no one can get high enough to touch it.
Hardly a speck in the blue overhead, ‘unmanned free balloons’ are the least regulated class of aircraft. With its Project Loon, Google is venturing into not one but two vast open spaces — the law and the sky.