Flight Information Region
|Term||Flight Information Region|
An airspace of defined dimensions within which flight information service and alerting service are provided.
ICAO, official definition, AN 2 Rules of the Air 2005
(EUROCONTROL, SASS-C Glossary definition) A three-dimensional area in which aircraft are under control of usually a single authority. Internally a FIR is divided into several geographical areas called sectors. Sometimes one or more FIRs have a combined upper area control.