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China's ‘Spy Balloon’ Explained by High-altitude Balloon Experts

From January 28th to February 4th 2023, a high-altitude balloon (HAB) of Chinese origin (dubbed in Western media as a 'spy balloon' and 'airship') was seen drifting across Northern American airspace. During its flight, the balloon flew over a nuclear warhead stationed in a silo field in Montana, causing a great deal of suspicion among authorities. Despite China’s claims that the craft was a meteorological balloon which veered off course, the Pentagon strongly insisted the balloon was being used to spy on sensitive military sites.

Following backing from the president, the blimp was shot down just off the South Carolina coast on live television by an F-22 fighter jet missile. Only time will tell whether the US’s response was necessary, as well as the nature of the technologies onboard the craft.

F-22 fighter jet shooting down a high-altitude balloon

Alongside this HAB, another Chinese balloon has been spotted travelling around Latin America and the Caribbean. According to Chinese officials, this is being used for “civilian purposes” and “flight tests”.

What was found on the Chinese High-Altitude Balloon?

Following the high-altitude balloons' dramatic descent from an altitude of 55,000 feet, an array of Coast Guard and Navy vessels rushed to the landing site situated off the Carolina coast to collect debris from the shallow waters (around 15 meters deep). So far, cameras, antennas, and sophisticated communication technology powered by solar panels have been found. The capabilities of this technology are still unknown. After landing, debris was spread over 7 miles. After all, the 'spy balloon' was 200 feet tall, approximately the height of a 20-story building.

When will we know what was on the 'spy balloon'?

A dock landing ship, a guided missile cruiser, and a salvage vessel are all set to arrive in the next few days to gather as much as they can from the remains of the balloon, along with FBI agents to categorize and assess the findings.

Did China's balloon violate international law?

If an entity (including the entity that launched China's balloon) plans to carry out a high-altitude balloon launch in a country or region, they have to apply for and gain approval from a relevant aviation authority. This applies to high-altitude balloons travelling across the US. Since the Cold War, the US has had its own ”air defence identification zone” requiring all aircraft to identify themselves and request approval before flying. However, in this unusual circumstance, the craft in question is a HAB, which isn't necessarily subject to the same laws and regulations as aeroplanes for example.

As a leading commercial high-altitude balloon flight operator, we regularly conduct international high-altitude balloon launches on a commercial basis. With over a decade of experience, we've built relationships with aviation authorities around the world, as well as a nuanced understanding of the regulations and procedures in place when conducting a high-altitude launch at any given location around the world. This expertise puts us in a good position to understand this multi-faceted controversy.

Weather balloons and high-altitude balloons under international law

High-altitude balloons (HABs), otherwise known as "weather balloons", are not only legislated for by individual sovereign states - they're also legislated for under international law. As part of the International Civil Aviation Organisation (ICAO), China, along with all other UN states are signatories to the "Chicago Convention", a treaty that upholds the jurisdiction of the ICAO and its framework on international aviation regulations and laws.

HABs are categorised aircraft by the ICAO which means that they have to follow international aviation law. International law is clear in regard to entities using balloons in another country’s airspace - every country has complete sovereignty over its own airspace, both for commercial and government aircraft. However, in the situation of China's 'spy balloon,' there is a catch. The upper limit of airspace ownership, as such, is not agreed upon in international law. At present, it usually extends to 45,000 feet (the maximum height military and commercial aircraft operate).

Was the 'spy balloon' flying at a height covered by space law?

China has tested the boundaries of international law with the recent "spy balloon" that floated above the US, making many of us ask where airspace ends and space begins. The Chinese weather balloon seen travelling across the US last week was flying at an altitude of 60,000 feet, placing it in a grey area where it's unclear immediately whether US law is usurped by 'space law'.

'Space law' at face value appears to be a spurious science fiction fantasy. In reality, space law is defined by a series of treaties and conventions, starting with the 1967 Outer Space Treaty (OST) which is clear in stating that: “Outer space, including the moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means.”.

Despite this seeming legal loophole, the 'spy balloon' at an altitude of 60,000 feet was not in an area that any international framework would describe as 'outer space', but it was instead well inside what is legally described in the US as “controlled airspace” within the ICAO framework. As a result, the US government will be fighting to reject any claims from China that the aircraft’s journey was acceptable according to US law, or that the debacle was a mere accident, especially if surveillance software and hardware are discovered in the wreckage. Speculators have a strong argument that the US was within its rights under international law to defend its sovereignty and "controlled airspace".

Was the Chinese weather balloon blown off course or was it all pre-planned?

Whilst the Chinese foreign ministry issued a statement that the US’s response was “an obvious overreaction and a serious violation of international practice” and have since filed a formal complaint with the US Embassy, propellers were found on the craft which was able to steer the balloon directly over sensitive US sites. As such, alarms were raised at the North American Aerospace Defense Command (NORAD).

If it is discovered that the high-altitude balloon was indeed employed for surveillance purposes and its trajectory cannot be boiled down to mere force majeure, it wouldn’t be the first time China tracked US territory without consent, and vice versa. The two nations have a long history of spying on each other.

The history of using balloons as spy satellites

Spy balloons, officially referred to as ‘reconnaissance satellites’ (Earth observation satellites deployed for military or intelligence purposes) are certainly not a new invention. Primitive balloons of this nature can be traced back centuries. During the Battle of Fleurus, in 1794, manned aircraft were used to monitor the enemy. Although they were initially used, albeit rather ineffectively, by both sides during the US Civil War, spy balloons came into more popular usage during The Cold War, between the years 1947 and 1991.

China & the US’s history of reconnaissance satellites

Since The Cold War, the US and China have been engaged in a game of spy satellite cat and mouse. From 1960 to the mid-1980s, photo satellite evidence was largely the only means to accrue information about nuclear threats. In light of this, The US embarked on project CORONA (a series of reconnaissance satellites primarily tracking the Soviet Union and China). Since then, the US has used hundreds of spy satellites to track the movements of its adversaries.

Cold War era spy satellite in space

Across the pond, China’s espionage against the US has been pretty extensive, with balloons of a similar nature traversing the continental US at least three times during the Trump administration. According to the Centre for Strategic and International Studies, “China has spy satellites flying over the United States every day, taking pictures, collecting radio signals and other data. Their space intelligence constellations have grown in number and improved dramatically in collection capabilities over the last 20 years.”

UPDATE: The 'spy balloon' story unfolds

In the coming weeks, we will have the answers to whether or not China’s balloons are part of a military surveillance programme, or are being used for other nefarious purposes. Since its entry into US airspace, the airship’s presence has already led to the Biden administration cancelling a trip to Beijing and increased political furore between the two nations. We will have to see what the future holds and if China’s interference really is the ‘greatest threat’ facing the US, as voiced by the former defence secretary, Mark T. Esper on CNN last Friday.

Feb 22nd: US Department of Defence releases an image taken by a US Air Force Pilot

It has been confirmed by the Pentagon that an image published by the US Department of Defence of China's spy balloon taken over the shoulder of a U2 spy plane's pilot is in fact authentic. The image is the most detailed view we've had of the spy balloon since the high-altitude espionage saga unfolded.

Chinese spy balloon seen over the shoulder of  a U-2 spy plane pilot

The payload of the spy balloon is believed to have consisted of a large solar array, with a wingspan of over 100 feet, which was used to power a sophisticated surveillance system.

Sent into Space’s balloon-assisted spaceflights are as low drama as you can get. Aside from the breathtaking views and epic ascent and descent footage, the only surveillance we conduct is keeping up to date with flight paths, and scanning our GPS systems to help us complete another successful trip to the skies. If you’d like to launch a spaceflight without receiving complaints from the US government, don’t hesitate to get in touch.

Sent Into Space high-altitude ballon in space with the Earth in the background


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