The criteria applied by Estonia in grouping aerodromes/heliports for the provision of information in this AIP are as follows:

1 Primary/major international aerodrome/heliport

The aerodrome/heliport of entry and departure for international air traffic, where all formalities concerning customs, immigration, health, animal and plant quarantine and similar procedures are carried out and where air traffic services are available on a regular basis.

2 Secondary/other international aerodrome/heliport

Another aerodrome/heliport available for the entry or departure of international air traffic, where the formalities concerning customs, immigration, health and similar procedures and air traffic services are made available, on a restricted basis, to flights with prior approval only.

3 National aerodrome/heliport

An aerodrome/heliport available only for domestic air traffic, including those military aerodromes/heliports where civil air traffic is allowed under certain conditions.