Balloon expert explains the challenges of shooting down China’s suspected spy balloon

Earlier this month, a suspected Chinese spy balloon drifted over much of the continental United States before an F-22 military fighter jet shot it down off the east coast. The event has put a massive strain on the already fragile U.S.-China relations, with China maintaining that the errant balloon was simply collecting weather data. Shooting down the balloon, Beijing said, was an “overreaction.”

The incident has thrown an unexpected spotlight on stratospheric balloon technology. High-altitude balloons themselves are not new: In fact, there are upwards of thousands of balloons operating in the stratosphere every day, Near Space Labs CEO Rema Matevosyan explained in an interview with TechCrunch. But it’s not every day that one is shot out of the sky, Top Gun-style.

Near Space Labs, an American company founded in 2017, operates a commercial fleet of high-altitude balloons. Near Space’s balloons — as well as the thousands of other weather and Earth observation balloons that currently float around the stratosphere — are equipped with various payloads, depending on their mission purpose. The ability to swap out payloads makes balloons a remarkably flexible platform for Earth observation, Matevosyan said.

She was hesitant to guess what information the Chinese balloon may have been capturing — “let’s wait for the data to be declassified on the sensors,” she suggested — but she did note that the Chinese balloon, and its payload, was notably larger than the many thousands of weather balloons that carry atmospheric sensors. The size of the payload on the Chinese balloon, which U.S. officials said was approximately the size of three school buses, could suggest that there were multiple types of sensors, she said.

There are also challenges with shooting down an object at such a high altitude. The stratosphere is much thinner than the lower regions of the atmosphere, and while you could pop the balloon with a pin if you got close enough — well, it’s impossible to get that close given the altitude limitations of commercial planes. Military jets like the F-22 are not engineered simply to carry missiles, but their unique shapes are optimized for maximum aerodynamic efficiency, speed and a lift/mass ratio, Matevosyan explained. According to the Department of Defense, the F-22 fired the Sidewinder missile at an altitude of 58,000 feet; the balloon was operating around 60,000-65,000 feet, so the missile didn’t have to travel very far across the stratosphere.

“The air is very thin,” Matevosyan said. “The stratosphere is closer to Mars’ atmosphere than Earth’s atmosphere. It’s actually very complicated to navigate. […] You really need a plane because you need very stable platforms to be able to send the missile.”

The big question — one that neither TechCrunch nor Matevosyan can answer — is, why shoot down this balloon? Why now? The Pentagon said that “instances of this kind of balloon activity have been observed previously over the past several years.” No doubt America spies on China in turn. Given that, many are left wondering why Washington decided that now was the time to draw a line in the sand. Whether the maneuver will indelibly escalate relations between the two countries, or end up just being another move in the Superpowers chess match, remains to be seen.