Class A airspace

Definitions

• Airspace from 18,000 feet MSL up to and including FL 600, including the airspace overlying the waters within 12 NM of the coast of the 48 contiguous states and Alaska; and designated international airspace beyond 12 NM of the coast of the 48 contiguo

References

• Pilot's Handbook of Aeronautical Knowledge
  Federal Aviation Administration · 2023