Which airspace classification is referred to as uncontrolled airspace?

The classification referred to as uncontrolled airspace is Class G. This type of airspace exists where air traffic control services are not actively managing air traffic, allowing pilots to operate freely without direct communication with ATC.

Class G airspace typically starts from the surface and extends up to a certain altitude, depending on the area, and it is often found in rural or less congested regions. Pilots flying in Class G airspace are responsible for their own navigation and separation from other aircraft, following visual flight rules unless operating under instrument rules.

In contrast, Classes A, B, and C are all considered controlled airspace where ATC services are provided, and specific communication or operating requirements for pilots are mandated. This distinction is crucial for understanding airspace management and pilot responsibilities.