13. Air Space and Outer Space Law

Air Space and Outer Space Law [1]




     Before the First World War, there were various theories dealing with the legal status of air space above States.[2]  One theory considered that the air space was entirely free and subject to no sovereignty.  Another considered that there was a zone of “territorial air”, analogy to the “territorial sea”, under the sovereignty of a State followed by a higher free zone.  A third theory considered that all the air space above a State was entirely within its sovereignty; while a fourth theory modified this view by positing a right of innocent passage through the air space for foreign civil aircraft.  Nevertheless, all theories agreed that the air space above the high seas and terrae nullius was free and open to all States.

     The outbreak of the First World War in 1914, with its recognition of the security implications of the use of the air space led to the arise of a new rule of customary law.  The military use of aircraft during the First World War meant that any rule which did not satisfy States’ concern of security would not be acceptable by them on security grounds.   States would not content with anything less than a complete sovereignty over their air space, unlimited by any right of innocent passage.  Since then, the customary rule has been that aircraft of one State have a right to fly over the high seas, but not over the territory or territorial sea of another State.  This rule is reaffirmed by the 1944 Chicago Convention on International Civil Aviation,[3] which provides that “every State has complete and exclusive sovereignty over the airspace above its territory”.[4]  The territory of a State consists “the land areas and territorial waters adjacent thereto under the sovereignty, suzerainty, protection or mandate of such State”.[5]

     Sovereignty of a State was understood to extend for unlimited distance into the airspace above its territory.  However this view has been modified by the law of outer space.

     To understand the contemporary international law concerning air space and outer space, it is necessary to devote the first section of this chapter to deal with the law of air space, followed by the second section dealing with the law of outer space.

Section 1:  The Law of Air Space


     The present law of air space which is centered on the regime concerning air navigation has developed from the Chicago Conference of 1944 and the conventions adopted there (such as, the 1944 Chicago Convention on International Civil Aviation, the 1944 Chicago International Air Services Transit Agreement, and the 1944 Chicago International Air Transport Agreement).  The 1944 Chicago Convention on International Civil Aviation is an international multilateral agreement concluded at the 1944 Chicago Conference.  This Convention lays down the fundamental principles of international air law and establishes the International Civil Aviation Organization (ICAO) as one of the specialized agencies of the United Nations.

     The 1944 Chicago Convention does not bring any major change in the international law of air, previously codified in the 1919 Paris Convention for the Regulation of Aerial Navigation.  It does state more detailed and refined rules, reflecting agreements on standards of air navigational practices.  It does not, however, provide the legal framework for international air traffic, which has been left to be regulated by bilateral agreements. Accordingly, States have concluded many reciprocal bilateral agreements concerning routes and traffic volume.

     The Chicago Convention reaffirms the basic principles of customary international air law. It provides that every State has complete and exclusive sovereignty over the airspace above its territory.[6]  It states the principle that aircraft have the nationality of the State in which they are registered (notably, many rules governing aircraft, provided in the Convention, have been copied from the rules governing ships).[7]  It makes a distinction between scheduled and unscheduled air services.  No scheduled international air service of one State may be operated over or into the territory of another State, except with the special permission or other authorization of that State, and in accordance with the terms of such permission or authorization.[8]  Aircraft not engaged in scheduled international air services have the right to make flights into or in transit non-stop across the territory of another State, and to make stops for non-traffic purposes without the necessity of obtaining prior permission of that State, subject, however, to the right of the State flown over to require landing, or to impose certain restrictions, such as routes and off-limit areas.[9]

     The Chicago Conventions applies only to civil aircraft, not to State aircraft which are used in military, customs and police services.[10]  State aircraft have no right to fly over the territory of another State or land thereon without authorization by special agreement or otherwise, and in accordance with the terms thereof.[11]

    The principle of complete and exclusive sovereignty over the national airspace is a firmly established rule of customary International Law.  It is unquestionably principle of the most fundamental principles of contemporary International Law. It is, however, qualified by various multilateral and bilateral conventions which permit aircraft to cross and land in the territories of the contracting States.

     Violation of national airspace by unauthorized foreign aircraft is a serious breach of International Law, and has led to many international incidents and disputes.  It has been questioned whether there exists a right of passage through the airspace over States, based upon the apparent similarity of treatment as regards sovereignty between the airspace and the territorial sea which centers upon the right of innocent passage that exists through territorial waters.  It is now accepted that no such right may be exercised in customary International Law.  Aircraft may only traverse the airspace of states with the agreement of these states, and where such agreement has not been obtained an illegal intrusion will be involved which will justify interception, though not (save in very exceptional cases) actual attack. 

     The principle of complete and exclusive sovereignty over national airspace does raise an important and controversial question regarding the boundary between national airspace and outer space.  This question remains undetermined and uncertain in International Law, because there is no agreement on the boundary between national airspace and outer space, and none of the conventions contains any provisions on the precise point where the airspace ends and outer space begins.  Thus, the rule that the sovereignty of a State extends over its airspace to an unlimited height has been one of the fundamental principles of the law of airspace.  However, this rule has been substantially modified as the result of the creation and development of the new law of outer space.  This matter is discussed below.


Section 2:  The Law of Outer Space                      


          Ever since the Soviet Union launched the first artificial satellite in 1957, space has constituted a new frontier to be discovered. Space technology and exploration have developed at an unimaginable rate.  International Law has had to keep pace with the rapid progress in this field.  The need to establish a legal regime to govern the activities in the outer space has been the central concern of the International Law.  Thus the law of outer space has emerged providing such legal regime to govern outer space and the activities therein.    

      Between the years 1957 and 1963, the General Assembly of the United Nations adopted six resolutions applicable to outer space.[12]  These resolutions were incorporated in the year 1967 in “the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies” (known in short as “the Outer Space Treaty of 1967”).[13]

     The 1967 Outer Space Treaty is an international multilateral agreement setting forth the fundamental international principles governing the outer space.  The outer space is the zone beyond the airspace surrounding the earth.  The Boundary between the airspace and outer space is an issue which remains undetermined and uncertain.  Neither the 1967 Outer Space Treaty nor any other conventions or treaties concerning airspace or outer space contains any provision on the precise point where the airspace ends and outer space begins.  Although States, so far, have not feel the urgency to establish a demarcation line between airspace and outer space, their practice provides sufficient evidence for the existence of the international rule that although national sovereignty, for security reason, must extend over the airspace up to a certain limit, it ends at some attitude above the earth. No State has insisted on its sovereignty to an unlimited height.  All States have conceded to unlimited over-flights of foreign satellites and spacecraft over their territories.  This practice infers that the sovereignty of a State over its airspace is limited in height at most to the point where the airspace meets the space. To determine such a point, proposals have been suggested basing on a variety of scientific and technological criteria.  Among these criteria are the theoretical limits of air flight or the lowest altitude at which an artificial satellite can remain in orbit; these criteria place the boundary of the airspace at around 50 to 100 miles.[14]

     Wherever outer space may begin, it is governed by International Law, including the Charter of the United Nations.  The international law of outer space consists mainly of the 1967 Outer Space Treaty,[15] the 1968 Rescue of Astronauts Agreement,[16] 1972 Liability for Damage Caused by Space Objects Convention,[17] the 1974 Registration of Objects in Space Convention,[18] and the 1979 Agreement Governing the Activities of States on the Moon and Other Celestial Bodies (the Moon Treaty).[19]  Beside these multilateral agreements, there are numerous regional and bilateral agreements on outer space cooperation, research and communications.

     The international law of outer space provides the fundamental principles relate to the outer space.  Among these principles are:


1.     Prohibition of national appropriation:  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. Outer space is “the common heritage of mankind” (res communis).

2.     Freedom of exploration: Outer space, including the moon and other celestial bodies, is free for exploration and use by all States without discrimination and in accordance with International Law, and there is free access to all areas of celestial bodies.

3.     The province of all mankind:  The exploration and use of outer space, including the moon and other celestial bodies, shall be carried out for the benefit and interests of all countries, irrespective of their degree of economic or scientific development.

4.     Ban on weapons of mass destruction:  It is prohibited to place in orbit around the earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction, and to install such weapons on celestial bodies, or station such weapons in outer space in any manner.

5.     The demilitarization of the moon and other celestial bodies:  The moon and other celestial bodies shall be used by all States exclusively for peaceful purposes.  The establishment of military bases, installations and fortification, the testing of any type of weapons, and the conducting of any military actions on the celestial bodies are forbidden. 

6.     The liability for damages: A State launching or procuring of launching of an object into outer space, including the moon and other celestial bodies, and the State from whose territory or facility an object is launched is internationally liable for damages caused to another State or to its nationals by such object or its component parts on the earth, in air space or in outer space, including the moon and other celestial bodies.

7.     Ownership of objects launched into outer space is not affected by their presence therein, or by their return to earth.

8.     A State on whose registry an object launched into outer space is carried retains jurisdiction and control over such object, and over any personnel thereof, while in outer space or on a celestial body.    

9.     The duty to avoid harmful contamination and adverse changes in the environment.

10.                        The duty to provide assistance to space vehicles and astronauts in distress, and to return them safely and promptly to the State of registry of their space vehicle.

11.                        The duty to inform the Secretary-General of the United Nations as well as the public and the international scientific community of the nature, conduct, locations and results of their activities in outer space, including the moon and other celestial bodies.

12.                        The duty to open all stations, installations, equipments and space vehicles on the moon and other celestial bodies to representatives of other States for inspection.


     Despite the growing body of rules of the international law of outer space, much remains to be done, particularly in the field of military uses of outer space, space navigation, telecommunications, and the unresolved question related to the boundary between the airspace and outer space.

[1]  See generally B. Cheng, Studies in International Space Law, oxford (1997); C.Q. Christol, Space Law, Deventer (1991); Malanczuk, chapter 13; and Shaw, chapter 10.

[2]  See Shaw, pp. 463-5.

[3]  Text in 15 U.N.T.S. 295.

[4]  The 1944 Chicago Convention on International Civil Aviation art. 1.

[5]  Id. art. 2.

[6]  Id. art. 1.

[7]  Id, arts. 17-21.

[8]  Id. art. 6.

[9]  Id. art. 5.

[10] Id. art. 3(a) & (b).

[11] Id. art. 3(c).

[12] See e.g. G.A. Res. 1721 (XVI); G.A. Res. 1884 (XVIII); and G.A. Res. 1962 (XVIII).

[13] Text in 610 U.N.T.S. 205.

[14] See Bledsoe & Boczek, p. 176.

[15] Text, supra note 13.

[16] Text in 63 A.J.I.L. (1969) 382.

[17] Text in 10 I.L.M. (1971) 965.

[18] Text in 1023 U.N.T.S. 15.

[19] Text in 18 I.L. M. 1434.