Description

National authorities establish vertical and horizontal separation standards to facilitate the safe navigation of aircraft in controlled airspace. Observance of these standards ensures safe separation from the ground, from other aircraft and from protected airspace (see Loss of Separation). Separation standards may sometimes serve to reduce exposure to Wake Vortex Turbulence although there are many occurences of significant wake vortex encounter at separations much greater than prevailing minimum separation.

National separation standards are based on the provisions of ICAO Doc 4444 (Procedures for Air Traffic Management), especially Chapter 5. Differences from these standards (if any) are published in national AIPs.