Chinese balloon row: Time to determine vertical delimitation in ASEAN

Delimitation of air and outer space has become a topical issue in the 21st century.


Ballooning tension: United States sailors assigned to Assault Craft Unit 4 prepare material recovered in the Atlantic Ocean from a Chinese high-altitude balloon for transport in Virginia Beach, Virginia, the US on Feb. 10. US jet fighters shot down the balloon on Feb. 4. (AFP/Ryan Seelbach/US Navy)

February 15, 2023

JAKARTA – On Feb. 4 the United States Air Force shot down a Chinese meteorological balloon flying over US airspace. This incident has since triggered fears about the worsening US-Sino relationship in the middle of tensions between the two giants in the Asia-Pacific.

Balloon operation is permissible under the International Telecommunication Union through the World Radio Conferences of 1979. Furthermore, the balloon is categorized as a High-Altitude Pseudo-Satellite (HAPS), an object stationed at an altitude of 20 to 50 kilometers and a specified nominal, fixed point relative to the Earth according to ITU Radio Regulations No. 1.66A.

The incident reminds us of the outer space delimitation inquiry and how high air space, thus the air law regime, may apply. No delimitation has internationally been agreed upon this issue, nor has the Chicago Convention of 1944 as the Magna Charta of air law that is closely bound with the Regulation of Aerial Navigation of 1919, also known as the Paris Convention. Both refer to the ancient Roman maxim “Cuius est solum eius est usque ad coelum et ad inferos,” which means whoever’s is the soil, it is theirs all the way to Heaven and all the way to Hell.

The Outer Space Treaty of 1967 (OST 1967) is also tacit on the delimitation issue. Yet, horizontal delimitation over air space is described in Article 2 of the United Nations Convention on the Law of the Sea of 1982 (UNCLOS 1982). States have sovereignty over their airspace within their territorial waters, but there is no consensus on vertical delimitation.

The silence of global conventions pertaining to delimitation issues cannot be separated from its development when the conventions were negotiated, as there is a limitation on atmospheric and space science. Referring to the International Civil Aviation Organization (ICAO), most aircraft fly below FL600 or 20 km since there are physical limitations to modern jet engines that need air flowing through its turbine. Still, there is no issue with rocket engines and balloon technology as these machines do not need airflow.

Currently, there are two approaches to delimitation issues, namely spatial and functionalism. The former focuses on where the air law regime ends and the space law regime begins with an exact altitude referred to as a vacuum area. It is widely known as the von Karman Line (100-120 km).

The functionalist approach has a different view. The functionalist oversaw whether the object’s function and intention would be launched for space purposes or not. The functionalist approach rejects the idea of a demarcation line between air and outer space.

Both approaches have to leave fatigue issues, because HAPS is considered a near-space object and not a full-space object. Google balloon is one example of HAPS. Neither object flew over the Karman Line as the functionalist approach.

Both concepts end with difficulties in determining where air and outer space delimitation shall begin. The shooting down of the Chinese balloon seems to have encouraged spatial doctrine as legal grounds to safeguard national defense.

Delimitation of air and outer space has become a topical issue in the 21st century. Such discussions have been ongoing at the United Nations Committee on the Peaceful Use of Outer Space (UNCOPUOS) for decades. A unique approach as a consensus, rather than voting mechanism, applies to ensure the sustainability of the result. It explains why progress takes so long without a certain foreseeable deadline.

Indonesia is among a few countries which have shown persistence in proposing delimitation at 100-110 km. Yet, the Indonesian Space Law of 2013 says such range can be applicable, at least for any space activities within the archipelago. Another example within the Asia-Pacific region is Australia, which has also set its delimitation around 100 km.

Keep in mind that there is no agreed delimitation on an international stage as each jurisdiction may vary.

The recent shooting down of the Chinese balloon should spark further discussions on delimitation to avoid potential conflict. In light of searching for legal certainty on delimitation, its absence should lead to establishing a code of conduct to avoid such a thing happening with ASEAN. This region is striving to maintain peace and stability. By chance, Indonesia is honored to chair ASEAN this year.

As the ASEAN chair, Indonesia can play a further role in space law by accommodating an exclusive economic utilization zone, as suggested by various space law experts who insist that the state has sovereign rights outside of its national air space.

One of the benefits of the utilization zone is that underlying states could control who could install vehicles above its air space. Furthermore, international standards would be established for HAPS operations that could encourage this sector to grow more significantly.

Underlying states have the rights to govern basic principles for safety and security issues and enjoy priority rights to use Near-Earth Objects (NEO) through the establishment of the utilization zone. According to Transparency Market Research, the HAPS business sector will grow to US$4.77 billion in 2023. Therefore, this area is promising particularly for Indonesia, which has an immense aerial area that could contribute to its economy.

Departing from precedence of the Exclusive Economic Zone (EEZ), the utilization zone would focus on economic benefits as well as the security and safety of underlying states. Currently, there is no robust or clear regulation concerning NEO, including interception manuals at the air force.

No wonder many countries react differently toward HAPS, as in the case of the recent Chinese balloon incident, which could discourage HAPS business.  


Ridha Aditya Nugraha teaches air and space law studies at Prasetiya Mulya University, Jakarta. Taufik Rachmat Nugraha is a researcher at the Centre for International Law (CIL), National University of Singapore. The views expressed are their own.


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