What is the minimum vertical separation required for aircraft operating at or below FL290 from active Special Use or ATC Assigned Airspace?

The minimum vertical separation required for aircraft operating at or below Flight Level 290 (FL290) from active Special Use Airspace (SUA) or ATC Assigned Airspace is 500 feet. This regulation is in place to ensure safe and efficient operations, allowing sufficient separation to prevent any potential conflicts between aircraft operating in or near these restricted airspaces.

When considering the separation requirements, it's important to recognize that the specifics can vary depending on factors such as type of airspace and operational context. Special Use Airspace may involve military operations and other controlled activities, requiring clear delineation between active operations and civilian air traffic. Therefore, the 500-foot vertical separation acts as a buffer to maintain safety and avoid inadvertent incursions into restricted airspace.

The other options reflect different separation standards that might apply under other circumstances or higher altitudes, but for operations at or below FL290 in relation to mutual or special use airspace, 500 feet is the regulatory requirement.