When operating under VFR at more than 3,000 feet AGL, what is the basis for determining cruising altitudes?

Determining cruising altitudes under Visual Flight Rules (VFR) at more than 3,000 feet above ground level (AGL) is primarily based on the magnetic course being flown. This principle stems from the FAA's regulations designed to enhance safety and situational awareness among pilots operating in controlled airspace.

When flying under VFR at altitudes above 3,000 feet AGL, a pilot must use the semi-circular cruising altitudes rule, which dictates that the altitude selection corresponds to the magnetic course of the flight. For example, if flying on a magnetic course of 0° to 179°, the appropriate cruising altitudes would be odd thousands plus 500 feet (such as 3,500, 5,500, etc.). Conversely, for magnetic courses of 180° to 359°, even thousands plus 500 feet would be used (like 4,500, 6,500, etc.). This system allows pilots to maintain appropriate vertical separation from one another, thus reducing the risk of mid-air collisions.

The correct focus on the magnetic course is essential for navigation and coordination among multiple aircraft in VFR conditions, making it a fundamental practice for maintaining safety in the skies.