International Air Law

(c) No state aircraft of a contracting State shall fly over the territory of another State or land thereon without authorization by special agreement or otherwise, and in accordance with its terms.

(d) Contracting States undertake, when issuing regulations for their state aircraft, to have due regard for the safety of navigation of civil aircraft.

Article 3 is a real limit on the Convention's reach. A military aircraft is outside it altogether, and its overflight is governed by article 3(c) and by general international law, including the prohibition of the use of force in [The Use of Force and Collective Security].

Article 4. Each contracting State agrees not to use civil aviation for any purpose inconsistent with the aims of this Convention.

Rights of flight: articles 5 to 7

Article 5, non-scheduled flight. All aircraft of other contracting States not engaged in scheduled international air services have the right, subject to the Convention, to make flights into or in transit non-stop across its territory and to make stops for non-traffic purposes without the necessity of obtaining prior permission, subject to the right of the State flown over to require landing, and subject to that State's right, for reasons of safety of flight, to require aircraft to follow prescribed routes or obtain special permission over inaccessible regions or regions without adequate air navigation facilities.

A stop for non-traffic purposes means a landing for refuelling or maintenance, not to pick up or set down passengers or cargo.

Article 6, scheduled air services, the article that governs commercial aviation. No scheduled international air service may be operated over or into the territory of a contracting State, except with the special permission or other authorization of that State, and in accordance with the terms of such permission or authorization.

Article 6 is why there are thousands of bilateral air services agreements. The Convention denies scheduled services any right of access and leaves each pair of States to negotiate. That is the opposite of the trade system in [General Principles of International Trade Law], where most-favoured-nation treatment multiplies every concession; in aviation each grant is bilateral and specific.

Article 7, cabotage. Each contracting State shall have the right to refuse permission to the aircraft of other contracting States to take on in its territory passengers, mail and cargo carried for remuneration or hire and destined for another point within its territory. And each undertakes not to enter into any arrangements which specifically grant any such privilege on an exclusive basis to any other State or an airline of any other State, and not to obtain any such exclusive privilege from any other State.

Two rules in article 7 and students give only the first. A State may reserve its domestic traffic to its own carriers, which every State does. And if it does open cabotage, it may not do so exclusively in favour of one State, which is a non-discrimination rule inside a permissive one.

The five freedoms, and where they actually come from

They are not in the Chicago Convention. They come from the International Air Services Transit Agreement and the International Air Transport Agreement, both concluded at Chicago at the same conference in 1944, and thereafter from bilateral air services agreements, which is where the commercial freedoms live in practice.

The two transit freedoms, in the Transit Agreement, sometimes called the Two Freedoms Agreement, which has wide participation:

First freedom: the privilege to fly across the territory without landing.

Second freedom: the privilege to land for non-traffic purposes.

The traffic freedoms, in the Transport Agreement, which attracted few parties and is of little practical importance, and in bilateral agreements:

Third freedom: to put down, in the territory of the other party, passengers, mail and cargo taken on in the territory of the State whose nationality the aircraft possesses.

Fourth freedom: to take on, in the territory of the other party, passengers, mail and cargo destined for the territory of the State whose nationality the aircraft possesses.

Fifth freedom: to take on and put down passengers, mail and cargo destined for or coming from the territory of any other State, that is traffic carried between two foreign countries on a route beginning or ending at home.

Later freedoms, up to a ninth, are commercial usage and not treaty terms, and cover such things as carriage between two foreign States without touching the home State, and cabotage. A student should name them as usage and not attribute them to any instrument.

Nationality of aircraft: articles 17 to 21

Article 17. Aircraft have the nationality of the State in which they are registered.

Article 18. An aircraft cannot be validly registered in more than one State, though its registration may be changed from one State to another.

Article 19. Registration or transfer of registration shall be made in accordance with the laws and regulations of the State concerned.

Article 20. Every aircraft engaged in international air navigation shall bear its appropriate nationality and registration marks.

Article 21 requires each State to supply, on request, information on the registration and ownership of any particular aircraft registered in it.

Compare the nationality of ships in [The High Seas] and of persons in [Nationality]. The technique is the same: registration confers nationality, nationality connects the object to a State, and the State of nationality is answerable for it. The difference is that article 18 forbids dual registration outright, whereas a person may hold two nationalities, and the Convention imposes no equivalent of the genuine link controversy.

Flight over territory, and the duties that go with it: articles 8 to 16

Article 8, pilotless aircraft. No aircraft capable of being flown without a pilot shall be flown without a pilot over the territory of a contracting State without special authorization by that State and in accordance with its terms, and each State undertakes to insure that such flight shall be so controlled as to obviate danger to civil aircraft.

Article 8 was written for a target drone in 1944 and it is the provision that now governs unmanned aircraft. Special authorisation, and control that obviates danger to civil aircraft.

Article 9, prohibited areas. Each contracting State may, for reasons of military necessity or public safety, restrict or prohibit uniformly the aircraft of other States from flying over certain areas of its territory, provided no distinction is made between the aircraft of the State itself and those of other contracting States engaged in similar services, the areas are of reasonable extent and location so as not to interfere unnecessarily with air navigation, and descriptions are communicated to the other States and to the Organization. The article also permits a State, in exceptional circumstances or during a period of emergency, or in the interest of public safety, to restrict or prohibit flying over the whole or part of its territory, on condition that such restriction or prohibition shall be applicable without distinction of nationality.

Articles 10 to 13, the ordinary obligations of entry. Landing at a customs airport where required (article 10); the applicability of air regulations, so that a State's laws on the admission and departure of aircraft engaged in international navigation apply without distinction as to nationality (article 11); rules of the air, under which each State undertakes to adopt measures to insure that every aircraft flying over or manoeuvring within its territory, and every aircraft carrying its nationality mark wherever it may be, complies with the rules in force, and to keep its own regulations uniform, to the greatest possible extent, with those established under the Convention (article 12); and entry and clearance regulations concerning admission, quarantine, customs and clearance, to be complied with by or on behalf of passengers, crew and cargo (article 13).

Article 12 is the article that makes the Annexes matter. Over the high seas the rules in force shall be those established under the Convention, and each State undertakes to insure the prosecution of all persons violating the applicable regulations.

Article 14, prevention of the spread of disease. Each contracting State agrees to take effective measures to prevent the spread by means of air navigation of cholera, typhus (epidemic), smallpox, yellow fever, plague, and such other communicable diseases as the contracting States shall from time to time decide to designate, and to consult with the agencies concerned with international regulations on sanitary measures applicable to aircraft.

Article 14 is where this chapter meets [The International Health Regulations], which regulate points of entry, conveyances and travellers in far more detail and to which a State's obligations under article 14 now largely refer.

Article 15, airport and similar charges. Every airport open to public use by national aircraft shall likewise be open under uniform conditions to the aircraft of all the other contracting States, and the same uniform conditions apply to air navigation facilities. Charges imposed for the use of airports and facilities shall not be higher than those which would be paid by national aircraft engaged in similar international services, shall be published and communicated to the Organization, and no fees, dues or other charges shall be imposed by any contracting State in respect solely of the right of transit over or entry into or exit from its territory of any aircraft of a contracting State or persons or property thereon.

Article 15 is a national treatment rule for airports, and its closing sentence forbids a charge levied simply for the right to overfly.

Article 16, search of aircraft. The appropriate authorities of each State shall have the right, without unreasonable delay, to search aircraft of the other contracting States on landing or departure, and to inspect the certificates and other documents prescribed by this Convention.

Facilitation, and the aircraft's papers: articles 22 to 36

Articles 22 to 24, facilitation. Each State agrees to adopt all practicable measures to facilitate and expedite navigation by aircraft between the territories of contracting States, and to prevent unnecessary delays to aircraft, crews, passengers and cargo, especially in the administration of immigration, quarantine, customs and clearance (article 22); undertakes so far as practicable to establish customs and immigration procedures in accordance with the practices established under the Convention (article 23); and provides that aircraft on a flight to, from or across the territory of another contracting State shall be admitted temporarily free of duty, with fuel, lubricating oils, spare parts, regular equipment and stores retained on board exempt from customs duties and similar charges, and spare parts and equipment imported for a registered aircraft admitted free of customs duty subject to the State's regulations (article 24).

Articles 25 to 27, distress, accidents and patents. Each State undertakes to provide such measures of assistance to aircraft in distress in its territory as it may find practicable, and to permit the owners or the State of registry to provide such measures of assistance as the circumstances may require, subject to the State's own control (article 25). In the event of an accident involving death or serious injury, or indicating serious technical defect, the State in which the accident occurs will institute an inquiry into the circumstances, in accordance so far as its laws permit with the procedure recommended by the Organization, and the State of registry shall be given the opportunity to appoint observers and shall be furnished with the report and findings (article 26). And authorized entry or transit shall not entail any seizure or detention of the aircraft or any claim against its owner or operator on the ground that the construction, mechanism, parts, accessories or operation of the aircraft is an infringement of any patent, design or model duly granted or registered in the State entered, the State undertaking not to require the deposit of security in respect of such a claim (article 27).

Article 27 is an unusual and practical provision, and it should be set beside [TRIPS]: a patent that would otherwise bite on an arriving aircraft is disapplied so far as the aircraft's entry and transit are concerned.

Article 28, facilities and systems. Each contracting State undertakes, so far as it may find practicable, to provide airports, radio services, meteorological services and other air navigation facilities in accordance with the standards recommended under the Convention, to adopt and put into operation the appropriate standard systems of communications procedure, codes, markings, signals, lighting and other operational practices and rules, and to collaborate in international measures to secure the publication of aeronautical maps and charts in accordance with the standards recommended.

Articles 29 to 31, the papers. An aircraft engaged in international navigation shall carry its certificate of registration, its certificate of airworthiness, the appropriate licences for each member of the crew, its journey log book, its radio station licence if equipped with radio, a list of passengers with places of embarkation and destination, a manifest and detailed declarations of cargo (article 29). Radio transmitting apparatus may be carried and used only if licensed by the State of registry, and only by crew members duly licensed by that State (article 30). Every aircraft engaged in international navigation shall be provided with a certificate of airworthiness issued or rendered valid by the State in which it is registered (article 31).

Articles 32 to 36, the crew and what may be carried. The pilot and other operating crew shall be provided with certificates of competency and licences issued or rendered valid by the State of registry, and each State reserves the right to refuse to recognise, for flight above its own territory, certificates and licences granted to any of its own nationals by another State (article 32). The journey log book shall be maintained in the prescribed form (article 34). Munitions of war or implements of war may not be carried in or above the territory of a State except by permission, and each State reserves the right to regulate or prohibit other articles in the interest of public order and safety (article 35). And each State may prohibit or regulate the use of photographic apparatus in aircraft over its territory (article 36).

Articles 39 to 42, the endorsement of substandard certificates. Where a person or article fails to satisfy in full the applicable international standard, particulars of the deficiency shall be endorsed on or attached to the certificate or licence (article 39), and no aircraft or personnel with such an endorsed certificate shall participate in international navigation except with the permission of the State or States whose territory is entered (article 40). Articles 41 and 42 save existing standards of airworthiness and of competency of personnel for aircraft and persons whose prototypes or licences preceded the international standards by the periods there stated.

The machinery of the Organization: articles 56 to 66

Articles 56 to 60, the Air Navigation Commission and the personnel. The Air Navigation Commission is composed of members appointed by the Council from persons nominated by contracting States, who shall have suitable qualifications and experience in the science and practice of aeronautics (article 56). The Council appoints the Secretary General and other personnel (article 58); the President of the Council, the Secretary General and other personnel shall not seek or receive instructions in regard to the discharge of their responsibilities from any authority external to the Organization, and each contracting State undertakes fully to respect the international character of their responsibilities and not to seek to influence any of its nationals in the discharge of them (article 59); and each State undertakes, so far as its constitutional procedure permits, to accord to the President, the Secretary General and other personnel the immunities and privileges accorded to corresponding personnel of other public international organizations (article 60).

Article 59 is Charter article 100 again, and the recurrence of that formula across the agencies is itself worth noticing.

Articles 61 and 62, money and the sanction. The Council submits to the Assembly an annual budget, annual statements of accounts and estimates, and the Assembly votes the budget and apportions the expenses among the contracting States on the basis it determines (article 61). The Assembly may suspend the voting power in the Assembly and in the Council of any contracting State that fails to discharge within a reasonable period its financial obligations (article 62), which is the same technique as Charter article 19.

Articles 64 to 66, other bodies and other agreements. The Organization may, with respect to air matters within its competence directly affecting world security, by vote of the Assembly enter into appropriate arrangements with any general organization set up by the nations of the world to preserve peace (article 64); the Council may, on behalf of the Organization, enter into agreements with other international bodies for the maintenance of common services and for common arrangements concerning personnel (article 65); and the Organization shall also carry out the functions placed upon it by the International Air Services Transit Agreement and by the International Air Transport Agreement (article 66), which is where the five freedoms in this chapter come from.

Air transport and the joint operating organizations: articles 67 to 79

Article 67. Each contracting State undertakes that its international airlines shall file with the Council traffic reports, cost statistics and financial statements showing among other things all receipts and the sources thereof.

Articles 68 to 76, facilities. A State may designate the route to be followed within its territory by any international air service and the airports which any such service may use (article 68); where the Council is of opinion that the airports or other air navigation facilities of a contracting State are not reasonably adequate for the safe, regular, efficient and economical operation of international air services, it shall consult with the State directly concerned and other States affected, with a view to finding means by which the situation may be remedied, and may make recommendations (article 69). A State may, in the circumstances of article 69, conclude an arrangement with the Council for giving effect to such recommendations, including the financing of facilities (article 70); the Council may, at the request of a contracting State, agree to provide, man, maintain and administer airports and other facilities, and may specify just and reasonable charges for their use (article 71); land required for such facilities is acquired or made available by the State (articles 72 and 73); technical assistance and the utilisation of revenues are governed by article 74; a State may at any time take over facilities provided by the Council in its territory, paying an amount which the Council determines to be reasonable (article 75); and funds obtained by the Council through reimbursement or from revenues shall be returned to the States which advanced capital (article 76).

Articles 77 to 79, joint operation. Nothing in the Convention prevents two or more contracting States from constituting joint air transport operating organizations or international operating agencies and from pooling their air services on any routes or in any regions, subject to the Convention including its provisions on the registration of agreements with the Council, and the Council shall determine in what manner the provisions of this Convention relating to nationality of aircraft shall apply to aircraft operated by international operating agencies (article 77). The Council may suggest to contracting States concerned that they form joint organizations to operate air services on any routes or in any regions (article 78), and a State may participate in joint operating organizations or in pooling arrangements, either through its government or through an airline company or companies designated by its government (article 79).

Other agreements, war, and the final articles: articles 80 to 96

Articles 80 to 83, existing and future arrangements. Each contracting State undertakes, immediately upon the coming into force of this Convention, to give notice of denunciation of the Paris Convention of 1919 and the Habana Convention of 1928 if it is a party to either (article 80); all aeronautical agreements in existence on the coming into force of the Convention between a contracting State and any other State, or between an airline of a contracting State and any other State or airline, shall be forthwith registered with the Council (article 81); the contracting States accept this Convention as abrogating all obligations and understandings between them which are inconsistent with its terms, and undertake not to enter into any such obligations and understandings (article 82); and, subject to article 82, a State may make arrangements not inconsistent with the provisions of this Convention, which shall be forthwith registered with the Council (article 83).

Article 89, war and emergency. In case of war, the provisions of this Convention shall not affect the freedom of action of any of the contracting States affected, whether as belligerents or as neutrals, and the same principle applies to a contracting State which declares a state of national emergency and notifies the fact to the Council.

Article 89 must be read with article 3. The Convention already excludes state aircraft; article 89 removes its restrictions altogether from a State at war or in a declared emergency, which is a very wide reservation and is the reason air law has so little to say about armed conflict.

Article 90, the Annexes. Adoption by the Council of the Annexes described in article 54(l) requires the vote of two-thirds of the Council at a meeting called for that purpose, and the Annex or amendment shall become effective within three months after its submission to the contracting States or at the end of such longer period as the Council may prescribe, unless in the meantime a majority of the contracting States register their disapproval with the Council.

Article 90 is the Chicago Convention's version of contracting out, and it is worth comparing with article 22 of the WHO Constitution in [The World Health Organization]: there a single Member escapes by objecting for itself, here a majority of States must disapprove to stop the Annex for everyone.

Articles 91 to 96, the final clauses. Ratification and entry into force on the thirtieth day after the deposit of the twenty-sixth instrument (article 91); adherence open to the members of the United Nations and States associated with them and States which remained neutral (article 92); admission of other States, subject to approval by any general international organization set up by the nations of the world to preserve peace, by a four-fifths vote of the Assembly and on such conditions as it may prescribe (article 93); amendment requiring approval by a two-thirds vote of the Assembly and entering into force for ratifying States when ratified by the number of States the Assembly specifies, which shall not be less than two-thirds of the total number of contracting States, with power in the Assembly to provide that a State which has not ratified within a specified period shall thereupon cease to be a member of the Organization and a party to the Convention (article 94); denunciation on notice to the Government of the United States, taking effect one year from the date of receipt, and available only three years after the Convention comes into effect (article 95); and definitions of air service, international air service, airline and stop for non-traffic purposes (article 96).

Article 94's power to expel a State that does not ratify an amendment is unusual and severe, and it should be compared with article 108 of the Charter in [The United Nations: Purposes, Principles and Membership], where an amendment simply does not enter into force without the permanent members.

Article 96 supplies the definitions this chapter has been using. An air service is any scheduled air service performed by aircraft for the public transport of passengers, mail or cargo; an international air service is an air service which passes through the air space over the territory of more than one State; an airline is any air transport enterprise offering or operating an international air service; and a stop for non-traffic purposes is a landing for any purpose other than taking on or discharging passengers, cargo or mail.

Technical uniformity: articles 33 and 37

Article 37. Each contracting State undertakes to collaborate in securing the highest practicable degree of uniformity in regulations, standards, procedures and organization in relation to aircraft, personnel, airways and auxiliary services, and to that end the Organization shall adopt and amend from time to time, as may be necessary, international standards and recommended practices and procedures dealing with communications systems, air navigation aids, airports, rules of the air and air traffic control practices, licensing of personnel, airworthiness, registration and identification, meteorological information, log books, maps and charts, customs and immigration procedures, aircraft in distress and investigation of accidents, and other matters concerned with the safety, regularity and efficiency of air navigation.

Those standards are adopted as Annexes to the Convention under article 54(l), and by article 38 a State that finds it impracticable to comply must notify the Organization of the differences between its own practice and the international standard. So the system operates by a duty to conform or to declare, which is a technique worth comparing with the contracting-out of [The International Health Regulations].

Article 33, recognition of certificates. Certificates of airworthiness and certificates of competency and licences issued or rendered valid by the contracting State in which the aircraft is registered shall be recognized as valid by the other contracting States, provided that the requirements under which they were issued were equal to or above the minimum standards established under the Convention.

Article 33 is what makes international aviation possible in practice: a pilot licensed in one State may fly into another without relicensing, because the licence is recognised.

The International Civil Aviation Organization: articles 43 to 55

Article 43. An organisation named the International Civil Aviation Organization is formed by the Convention, made up of an Assembly, a Council, and such other bodies as may be necessary.

It is a specialized agency within Charter article 57, brought into relationship with the United Nations under article 63, as [The Economic and Social Council] explains. Its seat is at Montreal.

Article 44, the aims and objectives. To develop the principles and techniques of international air navigation and to foster the planning and development of international air transport so as to:

(a) insure the safe and orderly growth of international civil aviation throughout the world;

(b) encourage the arts of aircraft design and operation for peaceful purposes;

(c) encourage the development of airways, airports, and air navigation facilities;

(d) meet the needs of the peoples of the world for safe, regular, efficient and economical air transport;

(e) prevent economic waste caused by unreasonable competition;

(f) insure that the rights of contracting States are fully respected and that every contracting State has a fair opportunity to operate international airlines;

(g) avoid discrimination between contracting States;

(h) promote safety of flight;

(i) promote generally the development of all aspects of international civil aeronautics.

The Assembly, under articles 48 and 49, meets not less than once in three years, each contracting State having one vote, decisions being by a majority of the votes cast unless otherwise provided. The Council, under articles 50 to 55, is a permanent body responsible to the Assembly, elected by it with adequate representation of the States of chief importance in air transport, those which make the largest contribution to the provision of facilities, and those whose designation will ensure that all major geographic areas are represented. Its mandatory functions in article 54 include adopting international standards and recommended practices as Annexes and notifying contracting States, and its permissive functions in article 55 include conducting research and investigating any situation which may appear to present avoidable obstacles to the development of international air navigation.

Disputes: articles 84 to 88

Article 84. If any disagreement between two or more contracting States relating to the interpretation or application of the Convention cannot be settled by negotiation, it shall, on the application of any State concerned, be decided by the Council. An appeal lies from the Council's decision to an ad hoc arbitral tribunal agreed with the other parties to the dispute or to the Permanent Court of International Justice, that reference now being read as to the International Court of Justice by virtue of article 37 of the Court's Statute, which is worked in [The International Court of Justice].

Article 87 obliges each contracting State not to allow the operation of an airline of a contracting State through the airspace above its territory if the Council has decided that the airline concerned is not conforming to a final decision under article 86, and article 88 provides that the Assembly shall suspend the voting power in the Assembly and in the Council of any contracting State that is found in default under the dispute provisions.

That is a stronger sanction than most of the instruments in this module carry, and it is worth noting for that reason.

Liability: from Warsaw to Montreal

The Chicago Convention regulates the public law of aviation. The liability of the carrier to the passenger is a separate line of treaties, and MU's label makes it fair to name them.

The Warsaw Convention of 1929, for the unification of certain rules relating to international carriage by air, established a regime of presumed fault with a limit on the carrier's liability, subject to loss of the limit for wilful misconduct, and required a ticket and an air waybill. It was amended repeatedly, by the Hague Protocol of 1955, the Guadalajara Convention of 1961 on carriage by a person other than the contracting carrier, and later protocols, producing what is called the Warsaw system, a patchwork in which different pairs of States were bound by different versions.

The Montreal Convention of 1999, for the unification of certain rules for international carriage by air, replaced that patchwork for States that joined it. Its principal features are a two-tier liability regime for death or bodily injury, under which the carrier is strictly liable up to a defined limit and, above it, liable unless it proves the damage was not due to its negligence or that of its servants and agents or was solely due to the negligence of a third party; a fifth jurisdiction permitting suit at the passenger's principal and permanent residence in defined circumstances; provision for advance payments; and the recognition of electronic ticketing.

India is a party to the Montreal Convention, and its Carriage by Air Act 1972 gives effect in Indian law to the Warsaw and Montreal regimes through its Schedules.

Security conventions

A third line of treaties answers unlawful interference, and naming them is enough: the Tokyo Convention of 1963 on offences and certain other acts committed on board aircraft; the Hague Convention of 1970 for the suppression of unlawful seizure of aircraft, which is the hijacking convention; the Montreal Convention of 1971 for the suppression of unlawful acts against the safety of civil aviation; and the Beijing instruments of 2010. Their common technique is the one described in [Extradition]: each party must establish jurisdiction, and a party in whose territory the offender is found must either extradite or prosecute.

A worked example

State AA's airline wishes to fly a scheduled service from State AA to State CC across State BB, stopping in State BB to refuel, and to carry passengers between two cities inside State BB. A private aircraft registered in State AA wishes to fly non-stop across State BB. State BB's military aircraft overflies State AA without asking. A passenger injured on the State AA airline sues.

The scheduled service across and into State BB. Article 6: no scheduled international air service may be operated over or into the territory of a contracting State except with the special permission or other authorization of that State. So State AA needs State BB's permission for both the overflight and the technical stop, unless the Transit Agreement grants the first and second freedoms between them.

The internal carriage inside State BB. Article 7: State BB has the right to refuse permission to take on in its territory passengers, mail and cargo carried for hire and destined for another point within its territory. That is cabotage, and it is refused as a matter of course.

The private non-scheduled flight. Article 5: aircraft not engaged in scheduled international air services have the right to make flights into or in transit non-stop across the territory and to make stops for non-traffic purposes without prior permission, subject to State BB's right to require landing and, for reasons of safety of flight, to prescribe routes.

The military overflight. Article 3(a) and (b): the Convention does not apply to state aircraft, and aircraft used in military, customs and police services are deemed state aircraft. Article 3(c): no state aircraft shall fly over the territory of another State without authorization by special agreement or otherwise. So State BB has acted unlawfully, and the matter falls to be judged under general international law and article 1.

The injured passenger. Not under the Chicago Convention at all. If both States are parties to the Montreal Convention of 1999, the carrier is strictly liable up to the defined limit and, beyond it, liable unless it proves the damage was not due to its negligence or that of its servants and agents, or was solely due to a third party's negligence, and the passenger may sue in one of the fora the Convention provides, including in defined circumstances the fifth jurisdiction of principal and permanent residence.

Change one fact: the flight crosses the exclusive economic zone of State BB rather than its territory. Article 2 defines territory as land areas and adjacent territorial waters, so the exclusive economic zone is outside it, and the freedom of overflight in the law of the sea applies.

Distinctions table

What it does NOT mean

There is no right of innocent passage in airspace. Article 1 makes sovereignty complete and exclusive.

The five freedoms are not in the Chicago Convention. They come from the Transit and Transport Agreements of 1944 and from bilateral agreements.

Article 5 does not permit commercial traffic. It covers non-scheduled flight and stops for non-traffic purposes.

The Convention does not apply to state aircraft. Article 3(a) and (b) exclude military, customs and police aircraft.

An aircraft cannot have two nationalities. Article 18 forbids dual registration.

The Chicago Convention does not govern carrier liability. That is the Warsaw system and the Montreal Convention of 1999.

Standards in the Annexes are not simply binding. Article 38 requires notification of differences where compliance is impracticable.

Limits and criticism

The bilateral system article 6 produced is inefficient. Access to markets is negotiated pair by pair, so an airline's rights depend on a network of separate agreements, and liberalisation has had to proceed by open skies agreements outside any multilateral framework, which is exactly what the trading system avoided by adopting most-favoured-nation treatment.

Article 1 gives no upper limit. Sovereignty is complete and exclusive over the airspace above the territory, and neither the Convention nor any later treaty says where that airspace ends, which is the unresolved boundary question [International Space Law] takes up.

Article 3 leaves military aviation outside the system, so the safety and traffic rules that govern civil flight do not bind state aircraft, and article 3(d) requires only due regard for the safety of civil aircraft.

Enforcement depends on the Council. Articles 84 to 88 give a real sanction, suspension of voting power and a duty on other States to close their airspace to a defaulting airline, and the machinery is used rarely, so the practical discipline is the technical system of standards and notified differences rather than adjudication.

Quick revision

Chicago Convention, 7 December 1944, in force 4 April 1947 after the twenty-sixth instrument. Preamble: aviation can greatly help to create and preserve friendship and understanding and its abuse can become a threat to the general security; services to be established on the basis of equality of opportunity and operated soundly and economically.

Article 1: every State has complete and exclusive sovereignty over the airspace above its territory. Article 2: territory is land areas and adjacent territorial waters. Article 3: applies only to civil aircraft; military, customs and police aircraft are state aircraft; no state aircraft may overfly or land without authorization; due regard for civil safety. Article 4: no use of civil aviation inconsistent with the aims.

Article 5: non-scheduled flights may transit and stop for non-traffic purposes without prior permission, subject to a right to require landing. Article 6: no scheduled international air service over or into a State except with special permission. Article 7: cabotage may be refused, and no exclusive cabotage grants.

Five freedoms, from the Transit Agreement (first and second) and the Transport Agreement and bilaterals (third, fourth, fifth): overfly; land for non-traffic purposes; put down traffic from home; take on traffic for home; carry between two foreign States on a route touching home.

Article 17: aircraft have the nationality of the State of registration. Article 18: no dual registration. Article 20: marks. Article 33: recognition of certificates and licences meeting the minimum standards. Article 37: uniformity, through international standards and recommended practices; article 38: notify differences.

ICAO, article 43: Assembly and Council; a specialized agency; seat Montreal. Article 44: safe and orderly growth, meeting needs for safe, regular, efficient and economical transport, preventing economic waste caused by unreasonable competition, a fair opportunity to operate international airlines, and avoiding discrimination.

Articles 84 to 88: disputes decided by the Council, appeal to an arbitral tribunal or the International Court; airspace closed to a non-conforming airline; suspension of voting power for a defaulting State.

Liability: Warsaw 1929 (presumed fault, limited), the Hague Protocol 1955, Guadalajara 1961; Montreal 1999, two-tier liability with strict liability to a limit and a fifth jurisdiction. India: the Carriage by Air Act 1972.

Security: Tokyo 1963, Hague 1970 (hijacking), Montreal 1971, Beijing 2010, all built on extradite or prosecute.

Test yourself

1. State the rule in article 1 of the Chicago Convention and contrast it with the law of the sea.

Article 1 provides that the contracting States recognize that every State has complete and exclusive sovereignty over the airspace above its territory. The word recognize shows that the Convention treats the rule as pre-existing customary law rather than as its own creation; complete means the sovereignty is not qualified by any general right of passage; and exclusive means no other State shares it. The contrast with the sea is direct and is worth marks. In the territorial sea a foreign ship enjoys a right of innocent passage, so it may pass without permission provided the passage is not prejudicial to the peace, good order or security of the coastal State. There is no equivalent in airspace: an aircraft has no right of innocent passage even over the territorial sea, and by article 2 the airspace above the territorial waters is sovereign airspace.

2. What is the difference between articles 5 and 6?

Article 5 concerns aircraft not engaged in scheduled international air services. Such aircraft have the right, subject to the Convention, to make flights into or in transit non-stop across the territory of a contracting State and to make stops for non-traffic purposes, that is for refuelling or maintenance, without the necessity of obtaining prior permission, subject to the right of the State flown over to require landing and, for reasons of safety of flight, to require prescribed routes or special permission over inaccessible regions. Article 6 concerns scheduled international air services, and it provides that no such service may be operated over or into the territory of a contracting State except with the special permission or other authorisation of that State and in accordance with its terms. The commercial consequence is that access for scheduled services is not granted by the Convention at all and must be negotiated, which is why bilateral air services agreements exist in thousands.

3. Where do the five freedoms of the air come from, and what are they?

Not from the Chicago Convention, which contains none of them. The first two come from the International Air Services Transit Agreement concluded at the same 1944 conference, and the traffic freedoms from the International Air Transport Agreement, which attracted few parties, and in practice from bilateral air services agreements. The first freedom is the privilege to fly across the territory of another State without landing; the second, to land there for non-traffic purposes; the third, to put down in the other State's territory passengers, mail and cargo taken on in the territory of the State whose nationality the aircraft possesses; the fourth, to take on in the other State's territory traffic destined for the home State; and the fifth, to take on and put down traffic destined for or coming from the territory of any other State. Freedoms beyond the fifth are commercial usage rather than treaty terms.

4. Explain cabotage under article 7.

Article 7 gives each contracting State the right to refuse permission to the aircraft of other contracting States to take on in its territory passengers, mail and cargo carried for remuneration or hire and destined for another point within its territory. That is the reservation of domestic traffic to national carriers, and every State exercises it. The article contains a second rule which is often omitted: each contracting State undertakes not to enter into any arrangements specifically granting any such privilege on an exclusive basis to any other State or to an airline of any other State, and not to obtain any such exclusive privilege from any other State. So a State that chooses to open its cabotage may not do so exclusively in favour of one partner, which is a non-discrimination rule operating inside a permissive one.

5. How does the Convention achieve technical uniformity?

Through articles 37, 38 and 33. Article 37 obliges each contracting State to collaborate in securing the highest practicable degree of uniformity in regulations, standards, procedures and organisation relating to aircraft, personnel, airways and auxiliary services, and requires the Organization to adopt and amend international standards and recommended practices covering matters such as communications, air navigation aids, airports, rules of the air and air traffic control, licensing of personnel, airworthiness, registration and identification, meteorological information, log books, maps and charts, customs and immigration procedures, aircraft in distress and the investigation of accidents. These are adopted as Annexes under article 54. Article 38 then requires a State that finds it impracticable to comply with an international standard to notify the Organization of the differences between its own practice and the standard. Article 33 completes the system by requiring each State to recognise certificates of airworthiness, certificates of competency and licences issued by the State of registration, provided the requirements under which they were issued were equal to or above the minimum standards.

6. What is the position on carrier liability to passengers?

It is governed by a separate line of treaties and not by the Chicago Convention. The Warsaw Convention of 1929 established a regime of presumed fault with a monetary limit on the carrier's liability, the limit being lost for wilful misconduct, and it was amended by the Hague Protocol of 1955, supplemented by the Guadalajara Convention of 1961 on carriage performed by a person other than the contracting carrier, and by later protocols, producing a patchwork in which different pairs of States were bound by different texts. The Montreal Convention of 1999 replaced that patchwork for its parties. It provides a two-tier regime for death or bodily injury under which the carrier is strictly liable up to a defined limit and, above that limit, liable unless it proves that the damage was not due to its negligence or that of its servants and agents, or was solely due to the negligence of a third party; it adds a fifth jurisdiction allowing suit at the passenger's principal and permanent residence in defined circumstances, provides for advance payments, and recognises electronic ticketing. India is a party, and the Carriage by Air Act 1972 gives effect to the regimes in Indian law through its Schedules.