1. Introduction
1.1 Definitions & abbreviations
| ADS-B | Automatic dependent surveillance – broadcast. A means by which aircraft can automatically transmit and/or receive data such as identification, position and additional data, as appropriate, in a broadcast mode via datalink. |
| Air traffic flow management (ATFM) | A service established with the objective of contributing to a safe, orderly and expeditious flow of air traffic by ensuring that ATC capacity is utilized to the maximum extent possible, and that the traffic volume is compatible with the capacities declared by the appropriate ATS authority. |
| Automatic Terminal Information Service (ATIS) | Automatic terminal information service, the automatic provision of current, routine information to arriving and departing aircraft. |
| Ceiling | The height above the ground or water of the base of the lowest layer of cloud below 20,000 feet covering more than half the sky. |
| Dependent parallel approaches | Simultaneous approaches to parallel or near-parallel instrument runways where radar separation minima between aircraft of adjacent extended runway centrelines are prescribed. |
| Global navigation satellite system (GNSS) | A worldwide position and time determination system that includes one or more satellite constellations, aircraft receivers and system integrity monitoring, augmented as necessary to support the required navigation performance for the intended operation. |
| Independent parallel approaches | Simultaneous approaches to parallel or near-parallel instrument runways where radar separation minima between aircraft of adjacent extended runway centrelines are not prescribed. |
| Independent parallel departures | Simultaneous departures from parallel or near-parallel runways. |
| Manoeuvring area | The part of an aerodrome used for take-off, landing, and taxiing of aircraft excluding aprons. |
| Multilateration (MLAT) system | A group of equipment configured to provide position derived from secondary surveillance radar (SSR) transponder reply signals primarily using time difference of arrival techniques. Additional information, including identification, can be extracted from the signals. |
| Near-parallel runways | Non-intersecting runways whose extended centrelines have an angle of convergence or divergence of 15 degrees or less. |
| Standard instrument arrival (STAR) | A designated instrument flight rule (IFR) arrival route linking a significant point, normally on an ATS route, to a point from which a published instrument approach procedure can be commenced. |
| Standard instrument departure (SID) | A designated instrument flight rule (IFR) departure route linking the aerodrome, or a specific runway on the aerodrome with a significant point, normally on a designated ATS route, at which the en-route phase of flight commences. |
1.2 Role of air traffic services
Air traffic services (ATS) primarily exist to expedite and maintain a safe and orderly flow of traffic. ATS ensures that collisions are prevented between aircraft, and between aircraft and other objects on the aerodrome surface.
ATS comprises of several services including flight information service, alerting service (for search and rescue), air traffic advisory service, and air traffic control service. Air traffic control service includes area control service, controlling larger sectors of airspace when aircraft are en route, approach control service which is responsible for separating and sequencing aircraft in the terminal area, and aerodrome control service which manages aircraft on or in the vicinity of an aerodrome.