Controlled Airspace 3 : Airspace, designated as continental control area, control area, control zone, or transition area, within which some or all aircraft may be subject to air traffic control
Ilan Kelman (ed.), Vulnerability and Resilience Definitions and References, Version 2, 2007. http://www.islandvulnerability.org/docs/vulnres.pd f, (Vulnr and Resilience - Brit) {524}