Pentagon Practiced Shooting Down Spy Balloons In Alaska Wargame Two Years Ago

The U.S. military appears to have anticipated the threat posed by Chinese balloons and has practiced tackling them for at least two years, according to Pentagon budget documents describing a classified program known as TRIPPWIRE. These also indicate that rather than there being a ‘balloon gap‘ as the Wall Street Journal recently suggested, the U.S. military may be well ahead in this technology – though its balloons are used rather differently from the Chinese ones.

TRIPPWIRE is a contrived acronym from “Tactical Responsive Intelligence, Surveillance, and Reconnaissance (ISR) Platforms and Payloads Watching Isolated Remote Environments.” It is a multi-year effort using stratospheric balloons as long-range, long-endurance observation platforms.

The scant details are provided in a program description in the Research and Development budget of the Office of the Secretary of Defense, an organization which manages activities where Army, Navy, Air Force and Space Force work together. TRIPPWIRE is described as “a DoD initiative to operationalize the stratosphere by offering increased demonstrations of high-altitude ISR and communication systems.”

The phase “operationalize the stratosphere” is a mantra for this program: the view is that experiments and prototypes have already shown the value of steerable stratospheric balloons able to navigate to a location and remain over it, now is the time for the services to use them in operations.

Plans show TRIPPWIRE was incorporated into “joint multi-domain demonstrations exercises, such as Northern Edge 21, Talisman Sabre, or Pacific Europe/Pacific Defender” to show “operational utility in operationally relevant environments with direct warfighter involvement and feedback.” In other words, getting troops to use the systems in realistic wargames.

TRIPPWIRE’s main focus is in using high-altitude balloons as sensor platforms and communication relays, providing similar capability to satellites but for a prolonged period and from much closer range. In addition, the document notes that “A Counter-Stratospheric Operations experiment will be conducted within TRIPPWIRE” – in other words, taking down balloons operated by opposing forces. In a wargame, this would most likely involve a simulated kill, but would have tested the U.S. capacity to detect, track, intercept and get into firing position with a virtual missile against a real target.

Media releases from Northern Edge 21, a giant wargame involving Air Force, Army, Marines and Navy units and held in Alaska in May 2021, show that stratospheric balloons were involved. Images were captioned with minimal information: “Ground crew members prepare and release an observation balloon” is a typical example.

Video from Northern Edge 21 shows a balloon strikingly similar to the Chinese one shot down off South Carolina, with a spherical envelope and an array of solar panels.

The U.S. has denied that it flies spy balloons over China, and while there may be an espionage balloon program, the military program is directed towards tactical use. According to the FY23 budget documents on the OSD’s Stratospheric Balloon program: “Demonstrations focus on evaluating how the Joint Force can leverage … operationalization of the stratosphere to refine hypersonic and long-range fires kill chains to counter time-sensitive targets.”

In other words, using balloons to spot things like moving vehicles or, specifically, mobile ballistic missile launchers. ‘SCUD hunting’ during Desert Storm proved to be largely futile, as Iraq’s mobile SCUD launchers were able to hide under bridges and inside buildings, firing missiles and getting out of the area before they could be targeted. Observation balloons teamed with new hypersonic missiles might be able to locate and strike such mobile units before they could carry out an attack.

Documents also mention one specific piece of hardware, stratospheric balloon called COLD STAR, for Covert Long Dwell Stratospheric Architecture, “equipped with autonomous navigation, high fidelity sensors, and on board algorithms to facilitate tasking, collection, processing, exploitation, and dissemination.” This has been carrying out operational demonstrations since 2020. The word ‘Covert’ suggests that COLD STAR may have some stealth features making it difficult to spot.

Images released during the Thunder Cloud live-fire exercise in Andoya, Norway, in September 2021 show the launch of an unspecified Raven Aerostar stratospheric balloon; according to the caption, this was used to provide target co-ordinates for long-range fire. This company has provided stratospheric balloons for NASA and a number of military programs.

There is little information available – “Details of this project are classified,” according to the description of the Stratospheric Balloon program. But there is enough to show that the Pentagon has been actively pursuing this technology for, is already flying the hardware, and has a pretty good idea about how to bring it down.

Which suggests that the recent shoot downs have been somewhat more calculated than the early breathless reports suggested. But it’s a good bet that ‘counter-stratospheric capability,’ once a very niche interest, is now enjoying a lot more attention than previously.