In which airspace do aircraft typically fly without any specific radar coverage?

In Class G airspace, which is also referred to as uncontrolled airspace, aircraft typically operate without specific radar coverage. This means that pilots in this airspace are not guaranteed air traffic control services, and they must rely on their own navigation and maintain situational awareness to avoid other aircraft.

Class G airspace extends from the surface up to the base of the overlying controlled airspace and is often found in rural, less densely populated areas where the demand for air traffic control services is lower. Pilots operating in Class G must comply with visual flight rules (VFR) and ensure they maintain visual separation from other aircraft, as there is no active oversight from air traffic controllers.

In contrast, Class C, Class D, and Class E airspaces all have varying degrees of radar coverage and require some level of communication with air traffic control. Class C and D are controlled airspaces where specific radar services are provided, and pilots must establish communication with the respective air traffic control facility, while Class E is a controlled airspace that can have radar coverage or not, but often involves some level of ATC interaction.