Cruising altitudes (semicircular rule)
Level cruise altitude depends on track (CAR 602.34). East/west split keeps opposite traffic at least 1,000 ft apart. VFR adds 500 ft to IFR thousands, so same-track VFR and IFR never share an altitude:
| Track | IFR | VFR |
|---|---|---|
| 000–179° (easterly) | odd thousands: 3,000 / 5,000 / 7,000 | odd + 500: 3,500 / 5,500 / 7,500 |
| 180–359° (westerly) | even thousands: 4,000 / 6,000 / 8,000 | even + 500: 4,500 / 6,500 / 8,500 |
When it binds:
| Flight | Binds in |
|---|---|
| VFR | level cruise above 3,000 ft AGL only |
| IFR | level cruise at every altitude (CAR 602.34(2)) |
| CVFR | binds too |
- Climbing or descending: neither binds, ATC may assign something else.
- Fly the table altitude or flight level unless ATC assigns one or the Minister authorizes otherwise in writing (TC AIM RAC 2.3.1).
Track reference (CAR 602.34(1)):
| Airspace | Track used |
|---|---|
| Southern Domestic Airspace (SDA) | magnetic track |
| Northern Domestic Airspace (NDA) | true track |
- Track = actual path over the ground, not heading. Apply variation first: east variation is subtracted (true 345°, 15°E, magnetic 330°; TP 1102 bearing example).
- Grid track is not the reference.
- Northern and Arctic Control Areas lie within NDA: true track (TC AIM RAC 2.6).
- True in NDA because horizontal magnetic field component diminishes near the magnetic North Pole, affecting magnetic compass systems (TC AIM RAC 2.2.1).
Above 18,000 ft ASL (TC AIM RAC 2.2.1(d); CAR 602.34):
- Table switches to flight levels (IFR and CVFR only).
- Controlled airspace, 18,000 ft ASL to FL 600 inclusive: must fly IFR unless the Minister authorizes otherwise in writing.
Full IFR ladder, 18,000 ft and below (CAR 602.34 table):
| Direction | Column | Altitudes (ft) |
|---|---|---|
| Easterly | I | 1,000 / 3,000 / 5,000 / 7,000 / 9,000 / 11,000 / 13,000 / 15,000 / 17,000 |
| Westerly | III | 2,000 / 4,000 / 6,000 / 8,000 / 10,000 / 12,000 / 14,000 / 16,000 |
Aerial survey/mapping exemption (CAR 602.34(3)): table does not apply if all of these hold:
- Contact ATC as early as possible.
- Supply a 1:500,000 or 1:1,000,000 topographical map of the survey area on request.
- File a flight plan or itinerary covering the area.
- In controlled airspace, fly the ATC clearance.
Trap: reading the wrong side of the 180° split, or putting +500 on the wrong rule set (VFR only, never IFR).
References
- CARs 602.34
- TC AIM RAC 2.2.1