Airspace - Classes, Structure, NOTAMs and Aerodromes
Structure
Canadian airspace is controlled Classes A to E, special-use Class F, and uncontrolled Class G. Class A begins at 18,000 ft ASL; Classes B, C and D cover the flight levels and terminal areas; Class D control zones typically extend 5 to 7 NM around airports up to about 3,000 ft above aerodrome elevation; Class E is controlled but does not require a VFR clearance for manned aircraft. Class G is where basic RPAS operations live.
Class F splits into advisory (CYA) areas, which flag hazards but do not prohibit entry, and restricted (CYR) areas, which require permission from the user or controlling agency. Many CYRs are active only by schedule or NOTAM, so the chart alone is never enough. Check NOTAMs before every flight: they activate restricted airspace, close runways, publish cranes and blasting, and change frequencies.
Aerodromes and charts
RPAS operations must stay 3 NM from an aerodrome unless authorized. The Canada Flight Supplement supplies aerodrome data, frequencies and hours; the VNC (1:500,000) shows airspace boundaries, control zones and aerodrome symbols; the VTA (1:250,000) adds terminal-area detail.
Traps
- "Uncontrolled" means Class G, not "no rules".
- Class E is controlled airspace even though no clearance is needed to enter it VFR.
- Chart altitudes may be ASL while RPAS limits are expressed AGL.
- CYA is advisory only; CYR is not.
- A control zone's top is above aerodrome elevation (AAE), not sea level.
Worked example
A site sits inside a Class D control zone 2.5 NM from a certified airport. It is simultaneously controlled airspace and inside the 3 NM aerodrome ring, so both permissions are needed; confirm with the CFS and current NOTAMs before applying. Rule of thumb: chart, CFS, NOTAMs - all three, every flight.