Minimum Heights

Minimum heights are the lowest altitudes at which flight is permitted over different areas under CASR Part 91. Over populous areas, aeroplanes must not fly below 1,000 ft above the highest feature or obstacle within a horizontal radius of 600 m of the point on the ground immediately below the aircraft. Over non-populous areas, aircraft must not fly below 500 ft above the highest feature or obstacle within a horizontal radius of 300 m of the point on the ground immediately below the aircraft.

Key Points

• •Populous areas (CASR 91.265): aircraft must remain at least 1,000 ft above the highest obstacle within a 600 m radius of the point on the ground directly below.
• •Non-populous areas (CASR 91.267): aircraft must remain at least 500 ft above the highest obstacle within a 300 m radius of the point on the ground directly below.
• •The horizontal radius is measured from the point on the ground directly below the aircraft, not from the aircraft itself.
• •Exceptions apply for take-off, landing, and approved low-level operations.

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