What is the altitude range for Class A airspace?

Class A airspace is defined as the airspace from 18,000 feet mean sea level (MSL) up to flight level (FL) 600, which corresponds to 60,000 feet MSL. This airspace is primarily used for high-altitude flights and is designated for instrument flight rules (IFR) operations only.

Within this airspace, all aircraft must operate under IFR, regardless of whether they are equipped for visual flight rules (VFR) or not. This regulation is in place to maintain safe separation between aircraft flying at these higher altitudes, where air traffic is more congested and requires more stringent safety measures.

Understanding the boundaries of Class A airspace is crucial for pilots, as it affects flight planning and communication with air traffic control, particularly in maintaining proper operational protocols.