Which airspace requires a minimum of 1000 ft vertical separation if less than 3 nautical miles apart?

The London Terminal Control Area requires a minimum of 1000 feet vertical separation between aircraft if they are less than 3 nautical miles apart. This regulation is essential for maintaining safe distances and reducing the risk of mid-air collisions in high-density air traffic regions. Terminal Control Areas commonly have stringent separation requirements due to the increased traffic volume, low altitudes of operations, and the diverse types of aircraft operating in those airspaces.

In comparison, other options like the Madrid Control Area, Prestwick Lower Airspace, and Beijing Approach Control may have different separation standards or may not be as strict in their vertical separation rules for aircraft operating in close proximity. Therefore, understanding and applying the specific separation requirements in the London Terminal Control Area is crucial for air traffic safety and efficient management of the busy airspace.