Southern Domestic Airspace (SDA)

Southern Domestic Airspace (SDA) is the portion of Canadian Domestic Airspace south of approximately 60°N latitude where magnetic variation is sufficiently stable and predictable that magnetic north provides a reliable directional reference for aviation. In the SDA, VFR cruising altitudes are based on magnetic track.

SDA Cruising Altitude Rule

In the SDA: 0°–179° MAGNETIC track — fly at odd thousands + 500 ft; 180°–359° MAGNETIC track — fly at even thousands + 500 ft. This rule applies at and above 3,000 ft AGL.

Related Terms

See also: Northern Domestic Airspace, Canadian Domestic Airspace, Cruising Altitude.