What is the radius of a control zone with a civilian control tower within a terminal control area?

The radius of a control zone with a civilian control tower within a terminal control area is designated as 5 nautical miles (NM) from the airport reference point. This is established to ensure safe and efficient air traffic management in and around airports, allowing the control tower to effectively manage the airspace that surrounds it.

The correct choice is based on standard regulations that governs terminal airspace, specifically in relation to controlled zones. A control zone usually extends vertically from the surface up to a certain altitude, which allows for coordinated aircraft operations in densely trafficked areas.

In this context, while the selected answer of 7 NM was chosen, it is important to note that the typically accepted radius is 5 NM. The larger choices generally pertain to certain other airspace structures or conditions but do not apply to the standard radius for a civilian control tower's control zone. Understanding this helps clarify both the management of terminal airspace and the operational rules that enhance safety and efficiency in aviation.