Beyond the territorial waters begin the high seas, and there the logic flips. Under the Convention on the High Seas (Geneva, 29 April 1958) the high seas are open to all nations, and no state may subject any part of them to its sovereignty: the freedoms of the high seas include the freedom to fly over them. That creates a question the Convention had to answer: if nobody's national law applies over the ocean, whose flying rules do? The answer: over the high seas, the Rules of the Air established under the Chicago Convention apply without exception (the internationally agreed rules of Annex 2, which the rules-of-the-air module of this course teaches in full). Over any state's territory, that state's own rules apply, and every aircraft flying there must obey them.
Flying into another state
Sovereignty makes permission the currency of international flying, and Part I of the Convention, titled Air Navigation, spells out which flights get that permission automatically and which must ask. The distinction runs between non-scheduled flights and scheduled services:
Right of non-scheduled flight — aircraft not engaged in scheduled international air services have the right, without prior permission, to fly into or across another contracting state's territory without landing, and to make stops there for non-traffic purposes: refuelling or maintenance, not picking up or setting down payload. The state overflown keeps the right to require a landing. These two rights are called the two technical freedoms of the air, and the next lesson places them in the full family of five freedoms.
Scheduled air services — a scheduled international air service may be operated over or into a state's territory only with that state's special permission or authorisation. An airline's timetabled route into a foreign country always rests on such an agreement, never on an automatic right.
Cabotage — carriage of passengers, mail or cargo for remuneration between two points inside the same state. Each state may refuse foreign aircraft that traffic; if it does grant the privilege, it may not grant it exclusively to any one other state, and it may not accept such an exclusive privilege itself.
Three more duties from Part I complete this picture:
Landing at customs airports — an aircraft entering a state's territory must, if that state so requires, land at an airport the state has designated as a customs airport, where entry formalities can be carried out, and it must likewise depart from one.
Rules of the Air — every aircraft over a state's territory must comply with that state's rules of the air, and each state undertakes to keep its own rules uniform, to the greatest possible extent, with those established under the Convention.
Search of aircraft — the authorities of each state have the right to search the aircraft of other states on landing or departure, without causing unreasonable delay, and to inspect the certificates and documents the Convention prescribes: the ramp inspection a crew may meet at any international airport has its legal root here.
Nationality, standards and differences
Part I also settles what nationality an aircraft has: an aircraft has the nationality of the state in which it is registered, it cannot be validly registered in more than one state, and its registration may be changed from one state to another. Registration creates a permanent legal link to that state: its certificates, its oversight and, for many purposes, its jurisdiction travel with the aircraft, which is why the state of registry appears constantly in this subject. Which rules of the air apply, though, is decided by where the aircraft is, as the sovereignty section established. The marks that display the registration, and the certificates that come with it, are the business of the next module.
The Convention's most productive idea is in its chapter on international standards and recommended practices (SARPs). Each contracting state undertakes to collaborate in securing the highest practicable degree of uniformity in regulations, standards and procedures, and ICAO adopts the agreed SARPs as the Annexes to the Convention. The SARPs come in two grades:
Standard — a specification whose uniform application is recognised as necessary for the safety or regularity of international air navigation; states are expected to comply with standards.
Recommended practice — one recognised as desirable; states should endeavour to follow recommended practices.
Uniformity cannot be forced, so the Convention builds in honesty instead: the notification of differences. A state that finds it impracticable to comply with an international standard in all respects, or that keeps regulations differing from it, must give immediate notification to ICAO of the differences, and the Council then notifies all other states. This is why national aviation publications carry lists of differences from ICAO Annexes: a pilot flying internationally is expected to know that the rules may differ and where to find out how.
The same chapter deals with what happens when an aircraft or a crew member does not meet an international standard: the particulars are endorsed on the certificate or licence, making the shortfall visible to any inspector, and an aircraft or crew member holding such an endorsed certificate or licence may not take part in international navigation except with the permission of every state whose territory is entered.
The mirror of that rule is recognition: certificates of airworthiness and licences issued or rendered valid by the state of registry must be recognised as valid by the other contracting states, provided the requirements they were issued under are equal to or above the minimum standards of the Convention. The ICAO minimums are what make a foreign certificate trustworthy; below them, recognition is not owed.
The documents on board
Part I closes the loop by listing the paperwork an aircraft in international navigation must carry, so that the search-of-aircraft right has something concrete to inspect. The list is exam material in its own right:
Certificate of registration — proves the aircraft's nationality and state of registry.
Certificate of airworthiness — proves the aircraft is fit to fly; the next module covers who issues and renews it.
Licences for each crew member — the appropriate licence for every member of the crew.
Journey log book — the running record of the aircraft's flights.
Radio station licence — if the aircraft is equipped with radio apparatus.
Passenger list — if passengers are carried: their names and places of embarkation and destination.
Cargo manifest — if cargo is carried: a manifest and detailed declarations of the cargo.
Two cargo-related duties travel with that list. Munitions and implements of war may be carried in or above a state's territory only with that state's permission, and each state may, for reasons of public order and safety, regulate or prohibit the carriage of other articles too. And each state may prohibit or regulate the use of photographic apparatus aboard aircraft over its territory: a rule written for an age of reconnaissance cameras that still stands.