Glossary

A
ACC

Area Control Centre, responsible for safe air traffic along ATS (air traffic service) routes. An ACC is divided into various sectors, each of which has clearly defined responsibilities. The procedures to transfer an aircraft from one sector to another between neighbouring states are clearly defined by international and bilateral agreements.

ADS B AND C

(Automatic Dependent Surveillance): an onboard localisation system by which each aircraft continuously broadcasts its position to the ground stations via satellite, providing a global view of the use of the airspace at all times.

ATC

(Air Traffic Control): a common term designating all the services provided to ensure and accelerate air traffic flow through a controlled airspace. ATC is subdivided into aerodrome control (TWR), approach control (APP) and area control (ACC).

ATIS

(Air Terminal Information Service): automatically transmits information to pilots which they need to take off from and land at an airport.

C
CANSO

(Civil Air Navigation Services Organisation): an international organisation of companies and authorities that provide air traffic services. CANSO’s core interests involve stepping up collaborations in key ATC areas such as quality, safety and customer service.

CNS/ATM

Communications, Navigation, Surveillance and Air Traffic Management.

D
DME

(Distance Measuring Equipment): navigation sensor that provides the pilot with information on distance to a ground station.

DTTLE

Portable emergency communications system.

DVOR

Doppler VOR - improves conventional VOR characteristics by applying the Doppler effect.

E
EGNOS

(European Geostationary Overlay System): a European system for satellite navigation designed to supplement the GPS (Global Positioning System) and integrate it into the GNSS (Global Navigation Satellite System).

F
FIR

(Flight Information Region): the world’s airspace is divided into a series of FIRs assigned to each State, which usually correspond to national borders and the length and breadth of their jurisdictional waters. They are subdivided if they are too large, such as in Spain, which has the Madrid FIR, Barcelona FIR and Canarias FIR; one part, south of the Madrid FIR, is delegated to the Seville Control Centre.

FIS

(Flight Information Service): a flight service which sees the ATS provide the necessary flight information to pilots through radiofrequency communications.

FREE ROUTE

A concept similar to free flight in which an ATCO will supervise aircraft flying on routes other than ATS ones, indicating an entry and exit point.

FREE-FLIGHT

A groundbreaking concept in the air navigation system of the future whereby pilots will be able to use advanced onboard equipment to determine and follow their own route, speed and altitude, in accordance with their needs, without being subject to a fixed route structure control by ATC.

G
GNSS

(Global Navigation Satellite System): generic ICAO term to designate satellite navigation based on available constellations (GPS or GLONASS) or future ones (GALILEO), plus augmentation to correct errors and perform accurate manoeuvres (WAAS, EGNOS, MSAS).

GPS

(Global Positioning System): a satellite navigation system of worldwide coverage.

I
IATA

International Air Transport Association.

IFR

(Instrument Flight Rules): a flight based on the aircraft’s onboard instruments. IFT traffic flies in a controlled airspace, using ATC services.

ILS

(Instrument Landing System): an instrument approach system which allows the pilot to perform the final approach manoeuvre before landing under low visibility conditions. The ILS sends two signals: a glide path that guides the pilot so that he/she can maintain the approach angle and a localiser which directs him/her, indicating possible lateral deviations with respect to the runway axis.

L
LVP

(Low Visibility Procedures): these procedures provide safety and order for aircraft traffic under adverse weather conditions and keep operations as smooth as possible.

N
NDB

(Non Directional Beacon): a navaid that provides the aircraft with its angle position with respect to magnetic north.

NOTAM

The acronym for Notice to Airmen.

R
RNAV

(Area navigation): a procedure by which the pilot follows a route in accordance with his/her needs and with the aircraft duly equipped, within a route structure determined by ATS.

RNP

(Required Navigation Performance): performance-based navigation.

RVSM

(Reduced Vertical Separation Minima): reduction of the standard vertical separation limits between aircraft flying IFR from 2,000 feet to just 1,000 feet, above FL290 and up to FL410 in dedicated areas with equipped and certified aircraft. RVSM was implemented in the North Atlantic (NAT) region in 1997 and in the European (EUR) region and Europe-South America (EUR-SAM) corridor in 2002.

S
SACTA

Automated System of Air Traffic Control. SACTA is the system that safely and automatically provides the air traffic controller with full information on all the data needed for his/her work (flight plans, communications, meteorological information, etc.). SACTA is used at all control centres and towers across Spain and is considered one of the most advanced systems in the world.

T
TMA

Terminal Control Area. A controlled airspace around one or various airports from where approach manoeuvres (landings and take-offs) are done.

U
UTC

(Coordinated Universal Time): known as Greenwich Mean Time (GMT), it is the universal civil aviation measurement to ensure that all operations across the globe keep the same time. Local time is measured and established in accordance with UTC; in Spain, the local time in summer is UTC+2, while in winter it is UTC+1.

V
VFR

(Visual Flight Rules): flight rules by which a pilot must orientate him/herself in reference to the terrain (mountains, railway lines, etc.). In these conditions the pilot is responsible for avoiding collision risks with the ground and other aircraft.

VOR

(VHF Omnidirectional Range): a short-range radio navigation system for aircraft. It indicates the aircraft’s direction with respect to magnetic north. This system has been improved with DVOR technology.