What are the provisions of international law on airspace?

Territorial airspace

Refers to the air above the territorial land and territorial waters of a country that is subject to national sovereignty.

Before the 20th century, there were different opinions on whether a country had complete sovereignty over its territorial land and territorial waters: ① It was believed that the entire space was free and unappropriable, and that the country had complete sovereignty over its territory. There is no sovereignty over the airspace; ② The space below a certain height above the ground is considered airspace, and the space above it is public space. Public airspace, like the high seas, is completely free and does not belong to any country; ③ Recognize the country’s sovereignty over airspace, but It is conditional on allowing innocent passage of foreign aircraft; ④ It is believed that the country has complete sovereignty over the territorial land and territorial waters, that is, the air space.

During World War I, aircraft began to become a tool of war. Both belligerent and neutral countries prohibit foreign aircraft from flying over their territories without permission. The former aims to consolidate national defense and the latter to protect neutrality. In terms of domestic legislation, some countries have enacted laws that exercise jurisdiction over the skies above their territories. For example, the British Air and Ship Law enacted in 1911 and amended in 1913 stipulates that the British government has the right to prohibit foreign aircraft from passing through the skies above British soil. Germany has the same law. Other countries have designated the skies over certain areas as restricted areas, prohibiting foreign aircraft from flying in.

The Convention on Aviation Management was concluded in Paris on October 13, 1919 after World War I and came into effect on July 11, 1922. It was referred to as the "Paris Aviation Convention" and was the first in the world. A treaty on air legislation. The Treaty recognizes “the complete and exclusive sovereignty of every State over the air space within its territory” (Article 1). At the same time, contracting states agree to grant each other freedom of innocent passage for civil aircraft in peacetime (Article 2). The Convention on International Civil Aviation, concluded in Chicago in 1944, follows the principles of the Paris Aviation Convention and reaffirms the absolute sovereignty of states over the airspace within their territories. Since the concept of "outer space" had not yet appeared at that time, some international legal scholars understood the term "complete and exclusive" in the above two conventions based on the so-called principle of Roman law that "the space above the land shall belong to the owner of the land". As "infinite height", it is believed that a country's sovereignty over its airspace is unlimited upward. However, with the launch of artificial satellites, the legal system for outer space has gradually taken shape. The legal principle that a country's air sovereignty (i.e. airspace) is limited to air space and cannot be extended to outer space has become increasingly accepted internationally. (See Outer Space).

The "Convention on International Civil Aviation" states' exercise of sovereignty over their airspace does not hinder the development of international aviation. The Convention on International Civil Aviation, concluded in Chicago on December 7, 1944, replaced the Paris Aviation Convention and formulated a series of principles and regulations for international civil aviation activities. The Convention first stipulates that all aircraft used for military, customs and public security purposes are state aircraft to distinguish them from civil aircraft. State aircraft may fly over or land in the territory of another Contracting State only with special agreement or permission. As for civil aircraft, they are divided into two categories: "not engaged in scheduled international aviation business" and "engaged in scheduled international aviation business". Under the conditions of complying with this Convention, the former has the right to fly over the territory of other contracting states without obtaining permission in advance, and has the right to make non-operational stops (such as refueling or repairs), but the country being overflew has the right to order it to land. Such aircraft also have the privilege of loading and unloading passengers, cargo and mail if they are used for reward or rental, but the country where the loading and unloading place is located has the right to stipulate relevant conditions or restrictions. As for scheduled aviation operations, they must obtain a license before they can conduct commercial flights over the territory of another country. This kind of concession generally takes the form of a bilateral agreement to stipulate business rights, flight routes, flight capacity (number of flights times the carrying capacity of the aircraft), procedures for approving freight rates, etc. Usually, the right to engage in transportation business between various points within a country is reserved to its own airlines.

For military needs or security reasons, a contracting state may establish restricted areas to prohibit aircraft from other countries from flying over. Unmanned aircraft are not allowed to fly into the airspace of other countries without special permission. In the event of war or the declaration of a state of emergency, a Contracting State is free to decide not to allow foreign aircraft to enter its airspace. The Convention also stipulates that aircraft should have the nationality of the country in which they are registered; aircraft engaged in international navigation must have one nationality. If it is registered in more than one country, it will be invalid. When aircraft of a Contracting State pass through or land at the airport of another Contracting State, they shall comply with the relevant flight, entry, release, immigration, passport, customs, health, safety and other regulations of the country on the ground. Aircraft of all Contracting States shall be treated equally without distinction based on their nationality.

Two agreements on international aviation. At the 1944 Chicago Conference, in addition to the "Convention on International Civil Aviation", two agreements were also signed. The first is the "International Air Transport Agreement", which stipulates the so-called "five freedoms": ① the privilege of flying over the territory of a country without landing; ② the privilege of non-operational landing; ③ unloading passengers and cargo loaded from the territory of the country where the aircraft belongs , the privilege of mail, ④ the privilege of loading passengers, cargo, and mail destined for the territory of the country to which the aircraft belongs; ⑤ the privilege of loading and unloading passengers, cargo, and mail destined for or from the territory of any other country. The other agreement is the International Air Transit Agreement, which only includes the first two freedoms.

Most of the participating countries signed the latter agreement, while the countries that signed the former agreement were less than half of the participating countries. Even the United States, which strongly supported the "Five Freedoms", withdrew from the International Air Transport Agreement in 1946. Until the early 1980s, efforts to conclude a universally accepted multilateral international convention on rights in civil aviation operations had not been successful. Civil aviation between countries is generally developed through bilateral agreements.

The People's Republic of China recognized the Chicago Convention on International Civil Aviation in 1974 and was elected as a member of the Council of the International Civil Aviation Organization in the same year. At the same time, it also cooperated with many countries on the basis of equality and mutual benefit. Countries have concluded bilateral agreements to promote the development of international civil aviation.