Airspace Classification

Airspace Classification is the ICAO framework that divides all airspace into seven classes (A through G), each with different rules for flight operations, pilot qualifications, and ATC services provided.

Class A: IFR only, full ATC separation, no VFR permitted
Class B: IFR and VFR, full ATC separation for all aircraft
Class C: IFR and VFR, separation between IFR-IFR and IFR-VFR, traffic info for VFR-VFR
Class D: IFR and VFR, separation for IFR only, traffic info for all
Class E: IFR and VFR, separation for IFR only, no service for VFR guaranteed
Class F: Advisory service for IFR (rarely used)
Class G: Uncontrolled, no ATC service required (but available on request)

Each country adapts these classes to local needs. Most controlled airports use B, C, or D.