In the context of aviation and aerospace, an Area Control Facility, also known as an Area Control Center (ACC), is a type of air traffic control facility responsible for controlling aircraft in a specific region or area, typically at higher altitudes.

The primary function of an Area Control Facility is to provide air traffic control services to aircraft operating at en route altitudes, which are typically above 18,000 feet (5,500 meters) above ground level. This includes:

1. Routing and guiding aircraft through the facility's assigned airspace, ensuring safe separation from other aircraft and obstacles.
2. Providing clearances, instructions, and advisories to pilots to ensure safe and efficient flight operations.
3. Managing air traffic flow, including sequencing and spacing aircraft to minimize delays and conflicts.
4. Coordinating with adjacent air traffic control facilities, such as approach control and tower facilities, to ensure smooth transitions and handoffs.

Area Control Facilities typically control aircraft within a specific geographic area, such as a state, region, or section of a country. They may also be responsible for multiple sectors or regions, depending on the complexity of the airspace and the volume of air traffic.

Some examples of Area Control Facilities include:

• Center control facilities in the United States, which are responsible for controlling high-altitude air traffic within specific regions.
• Area control centers in Europe, which are responsible for controlling air traffic within specific regions or countries.
• Upper area control centers, which control air traffic at very high altitudes, typically above 24,000 feet (7,300 meters) above ground level.

Overall, Area Control Facilities play a critical role in ensuring the safe and efficient movement of air traffic through the national airspace system.