The bilateral framework

Plane blue sky background

International air services (apart from services within the European Union) are governed by the provisions of inter-governmental instruments. These instruments are usually in the form of air services agreements (ASA) - which are formal treaties between countries - accompanying Memoranda of Understanding (MoU) and exchanges of formal diplomatic notes. It is not essential to have an ASA in place for international services to operate, but the cases where services exist and there is no treaty are rare.

ASAs cover the basic framework under which airlines are granted economic bilateral rights to fly between two countries. The frequency, capacity and other operational issues are normally covered by MoUs.

The bilateral system has its basis under the Chicago Convention and associated multilateral treaties. The Chicago Convention was signed in December 1944 and has governed international air services since then. Nearly 200 countries are signatories to the Convention. The Convention also has a range of annexes covering issues such as aviation security, safety oversight, air worthiness, navigation, environmental protection and facilitation (expediting entry and departure at airports).

The International Air Transport Agreement of December 1944 defined the five “freedoms of the air” (where the following definitions relate to aircraft registered in state A):

  • 1st freedom - the right to fly over state B without commercial or technical stops
  • 2nd freedom - the right to land in state B for technical purposes, e.g. refuelling
  • 3rd freedom - the right to set down traffic from state A in state B
  • 4th freedom - the right to pick up traffic in state B destined for state A
  • 5th freedom - the right to pick up traffic in state B destined for state C or put down traffic in state B originating in state C

In addition, other “freedoms of the air” are often referred to. Although not formally defined, these are commonly understood as follows:

  • 6th freedom - a service taking passengers between states B and C which flies via state A
  • 7th freedom - a service between state B and state C operated by airline of state A (also called a “free-standing fifth freedom”)
  • 8th freedom - cabotage, picking up and setting down traffic within the borders of state B by an aircraft registered in state A

3rd and 4th freedoms are always granted together. 6th freedoms are effectively two 3rd/4th freedom services linked together, each of which are operated under the relevant bilateral agreement. These are not rights “granted” under an ASA but they are controlled under the tariff and “primary justification” provisions of an ASA.