THE UNITED STATES says that the high-altitude balloon it shot down at the weekend that China says was a strayed weather balloon was not a one-off but part of a globally deployed fleet of stratospheric surveillance balloons.
US Secretary of State Antony Blinken says Chinese balloons ‘have violated the sovereignty of countries across five continents’ and that Washington was sharing information from the one it shot down with various governments.
US officials have been briefing that the fleet operates from Hainan Island, home to the People’s Liberation Army (PLA)’s Southern Theatre Command, and over the years has flown spying missions over Japan, Vietnam, India and Taiwan, among other countries, including previous overflights of the United States. One flew over South America concurrently with the flight of the one the United States shot down.
The one shot down, US officials say, was carrying devices to intercept communications — sigint gathering, in the jargon — among other surveillance equipment. Its solar panel array would have provided sufficient power for multiple surveillance devices.
Based on research papers published in recent years, the People’s Liberation Army (PLA) has been showing interest in the military applications of ballons, including as a means to test the air defences of adversaries as well as for electronic surveillance and supporting PLA-Air Force attack missions. Chinese military researchers have also been looking at the way the United States uses high-altitude balloons as part of its early warning systems against missile attacks and to supplement ground-based air defence systems.
The Chinese Academy of Sciences’ Aerospace Information Research Institute and Institute of Optics and Electronics are also researching stratospheric balloons for near-space use. They have conducted test launches, including balloons claimed to be capable of carrying payloads of over 1,000 kilogrammes. While these have civilian uses, such as land imaging and environmental mapping, the technology would readily transfer to military use.
US officials’ descriptions of the downed Chinese balloon suggest that it is at least ten times larger in diameter than a typical weather balloon and carried a payload of at least 900 kilogrammes, compared to the less than 200 grammes typical of the small and expendable measuring device called a radiosonde that weather balloons usually carry. It also appears to have been made of a plastic film, not latex, which is the usual material for weather balloons — and why they burst relatively quickly, giving short flying times, nothing like the days the downed balloon took to traverse Canada and the United States.
Larger balloons carrying equipment for civilian high-altitude photography and videography would be three times larger than a typical weather balloon but still only a third of the size of the one shot down.
The Foreign Ministry has said it does not know which company owns or manufactured the downed balloon. However, US officials have said they have identified a balloon manufacturer that sells to the PLA.
Weather balloon manufacture in China is dominated by Zhuzhou Rubber, part of state-owned ChemChina, which makes 75% of high-altitude balloons used by the China Meteorological Administration (CMA).
The CMA has its roots in the military but has been a civilian agency since the mid-1990s. It is highly unlikely the one shot down was one of its. Earlier this month, it said it had seven meteorological satellites in orbit. These could be used as relays to transmit data from high-altitude balloons back to ground stations.
The other manufacturer capable of making balloons that fly at that height is Guangzhou Double-One Weather Equipment. It has said the downed balloon was not one of its.
A US Air Force defence contractor, Raven Aerostar, and another US company, World View Enterprises, make stratospheric balloons of similar size and capacity to the Chinese one. These are ‘steered’ by moving them up or down to catch air currents moving in the desired direction. The Chinese balloons likely operate in the same way.
It is easy to imagine a fleet of stratospheric balloons able to communicate with each other and form a high-altitude mesh network providing real-time coverage of what is below — whether environmental conditions or military assets — from near-space and using the increasing constellations of communications satellites being put into space by US and Chinese entities to relay their data back to earth.
The 14th Five-Year Plan (2020-25) identifies the development of a national broadband satellite constellation as a policy goal, and earlier this week Beijing announced a licencing system for satellite internet providers.
Our man in Washington tells us that the US is now considering sanctions against Chinese balloon makers that sell to the PLA.
Stratospheric ballooning has its technical challenges, but they are not exactly rocket science, so to speak. Its wide application to civilian use will make it a new and particularly querulous front in the contention over dual-use technologies between Washington and Beijing.