International Civil Aviation Organisation (ICAO)

International Civil Aviation Organisation (ICAO)


The constitution of ICAO is the Convention on International Civil Aviation, drawn up by a conference in Chicago in November and December 1944, and to which each ICAO Contracting State is a party. This Convention is also known as the Chicago Convention. In October 1947, ICAO became a specialised agency of the newly-established United Nations. The Chicago Convention set down the purpose of ICAO:

"WHEREAS the future development of international civil aviation can greatly help to create and preserve friendship and understanding among the nations and peoples of the world, yet its abuse can become a threat to the general security; and WHEREAS it is desirable to avoid friction and to promote that co-operation between nations and peoples upon which the peace of the world depends; THEREFORE, the undersigned governments having agreed on certain principles and arrangements in order that international civil aviation may be developed in a safe and orderly manner and that international air transport services may be established on the basis of equality of opportunity and operated soundly and economically;”

There are currently 191 Member States.

How ICAO Works

The following description is given by ICAO itself:

"According to the terms of the Convention, the Organization is made up of an Assembly, a Council of limited membership with various subordinate bodies and a Secretariat. The Chief Officers are the President of the Council and the Secretary General.

The Assembly, composed of representatives from all Contracting States, is the sovereign body of ICAO. It meets every three years, reviewing in detail the work of the Organization and setting policy for the coming years. It also votes a triennial budget.

The Council, the governing body which is elected by the Assembly for a three-year term, is composed of 36 States. The Assembly chooses the Council Member States under three headings: States of chief importance in air transport, States which make the largest contribution to the provision of facilities for air navigation, and States whose designation will ensure that all major areas of the world are represented. As the governing body, the Council gives continuing direction to the work of ICAO. It is in the Council that Standards and Recommended Practices are adopted and incorporated as Annexes to the Convention on International Civil Aviation. The Council is assisted by the Air Navigation Commission (technical matters), the Air Transport Committee (economic matters), the Committee on Joint Support of Air Navigation Services and the Finance Committee.

The Secretariat, headed by a Secretary General, is divided into five main divisions: the Air Navigation Bureau, the Air Transport Bureau, the Technical Co-operation Bureau, the Legal Bureau, and the Bureau of Administration and Services. In order that the work of the Secretariat shall reflect a truly international approach, professional personnel are recruited on a broad geographical basis.

ICAO works in close co-operation with other members of the United Nations family such as the World Meteorological Organization (WMO), the International Telecommunication Union (ITU), the Universal Postal Union, the World Health Organization (WHO) and the International Maritime Organization (IMO). Non-governmental organisations which also participate in ICAO's work include the International Air Transport Association International Air Transport Association (IATA), the Airports Council International (ACI), the International Federation of Air Line Pilots' Associations International Federation of AirLine Pilots Associations (IFALPA), and the International Council of Aircraft Owner and Pilot Associations (IAOPA)."

ICAO is responsible for:

  • Safety
  • Registration
  • Airworthiness
  • Prevention of economic waste
  • Fair competition
  • Standardisation
  • Aviation Law


The ICAO Annexes

The separate article "ICAO Annexes and Doc Series" gives details of all 19 annexes and ICAO Documents.

Contracting States are required to give notification of differences to standards, and invited to notify differences from Recommended Practices in Annexes. This information is then listed in Supplements to the Annexes.

It should be noted that ICAO Standards do not preclude the development of national standards which may be more stringent than those contained in an Annex.

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