national airspace. Int’l law. The pillar of air above a nation’s territory — including internal waters and the territorial sea — over which it has complete and exclusive sovereignty and through which foreign aircraft have no right of innocent passage. • There is no agreement on the boundary between national airspace and outer space.
navigable airspace. The area above the legally established minimum flight altitudes, including the area needed to ensure safe takeoffs and landings of aircraft. 49 USCA § 40102(a)(30). [Cases: Aviation 3, 231. C.J.S. Aeronautics and Aerospace §§ 7–9, 21, 73.]