What defines Class G airspace?

Class G airspace is defined as uncontrolled airspace that is not depicted on sectional charts and is typically located beneath underlying controlled airspace. This means that while it exists, it does not require the same level of oversight and control as other classes of airspace designated for operations by air traffic control.

The absence of depiction on sectional charts indicates that this airspace does not have the same restrictions or operational procedures as controlled airspace, providing pilots more flexibility in their flight paths. Class G airspace is often used for general aviation, especially in areas where traffic is lighter or in more rural locations, and though it has fewer regulations, pilots must still adhere to visibility and cloud clearance criteria to ensure safety.

Regarding the other options, controlled airspace is typically marked on sectional charts and includes Classes A, B, C, D, and E, which impose varying levels of restrictions. Airspace with restrictive flying hours does not define Class G, since this type of airspace tends to be available for use at all hours without such limitations. Lastly, prohibited airspace for national security pertains specifically to zones designated for restricted access, which is distinct from the nature of Class G airspace.