At the end of the ‘40s an important development in aviation took place, the number of aircraft and commercial flights were growing and as a consequence Air Navigation was born. The result of these important changes was the creation of a new and peculiar activity: Air Traffic Control

Aviation pioneers used to fly just by looking through the horizon and make use of some land references and basically guided by their own senses, intuition and skills developed by their practice and strong desire to fly.

It became an important matter to count with reliable air transport, this is why on board certain instruments such as compass and coordinates were used, and also it became necessary to develop aids in land. The first aerial night route was implemented in 1921, when some “Radio Beacons” were installed between Columbus and Daytona, Ohio, USA; they were visible to pilots, had a separation distance of 80nm and spun every 10 seconds. Lately the introduction of radiotelegraphy allowed pilot and people in land to communicate; these last ones would send/transmit meteorological reports.

Little by little technological advances were adapted to the aeronautic media; also some land/terrestrial aids were implemented such as the construction of “Radio Beacons” circa 1932, being this ones the predecessors of radio aids.

Air Traffic Control Services were born because of the increase number of airborne operations which made necessary to introduce/implement/create certain type of co-ordinate control. The basic unit of Control was Time. The pilot and people in land must have to register the exact time of the take off and according to that information the time of “fixed crossings” and landings was calculated.

The development of the Radar in the early ‘40´s represented a significant contribution to aviation and therefore to air navigation security. Later, as this way of transport became more evolved, it was vital to count with rules and basic principles in order to establish the initial management of civil aviation.

In 1944 took place in the city of Chicago an International Conference of Civil Aviation where was created the International Civil Aviation Organization (ICAO) its objective up to this days is to assure the international cooperation between countries in order to unify the regulations and procedures in the matters of international civil aviation. Mexico as a member of this Organization must give navigation services to the extended area of the national territory and also to some parts over the Pacific Ocean and Gulf of Mexico.

Air Traffic Services

Air Traffic Services are provided directly by the ATC to the aircraft and are divided in three main types: Approximation Service, Aerodrome Control Service and Area Control Service.

Aerodrome Control Services

This service is provided by the Air Traffic Controller from the Control Tower to all the flying aircraft in the immediate proximity of the airport and the ones circulating in its maneuver areas such as: runway and platform.

Runway: is the strip on which aircraft take off and land, a basic rule is that in a runway two airplanes cannot be placed at the same time.

Taxiway: are the spaces which join the runways with the platforms

Platforms: are the spaces where aircraft park to be filled with oil and where maintenance can also be given

Control Tower: it is the place where air traffic controllers are situated and from where they can fulfill their job. These buildings should allow the air traffic controllers to have a complete and clear visibility over the area they are in charge of, also it should be equipped with the necessary tools to be able to communicate with other aircraft, with other airport dependencies and with other control units such as Approximation Control and Area Control Center.

The assigned air space for this service is a five mile cylinder being the airport its center and having a height of 2,000 ft in a vertical plane over the land surface.

Approximation Services

This service is provided by the Air Traffic Controllers placed in Approximation Control Units or also it can be from a Control Tower or from an Area Control Center.

Control Terminal Area is a controlled air space established in the airports which count with Approximation Service and it extends up to 50 miles of radio with its center in the airport and has an altitude of 20000 ft , this service is given to the aircraft flying by a flight plan by instruments inside the terminal area and enter or depart from one or more airports inside that area.

This service is given to the arriving flights by maintaining and helping them when is descending to the assigned landing strip. Also it is given to the departing flights directed to the airways previously set up in the flight plan, maintaining the separation distance.

The Approximation Control Units keep a closed communication and coordination with the Control Towers and Area Control Center to exchange information and instructions concerned with the circulation area inside its jurisdictional space.

Area Control Services

Area Control Service is provided from the Control Centers to all the aircraft with a flight plan by instruments flying along the airways assigned as controlled air space, it is extended from the minimum altitude of the airways up to 20,000 ft to the top.

Area Control Service has the responsibility of a great dimension of air space, for this reason it has to be divided in control sectors each one attended by different teams of air traffic controllers, distributed to them as equally as possible.

In the country there are four Control Area Centers: in Mexico City, in the city of Monterrey, also in Mazatlan and in the city of Merida.

Air Space

Navigation Services are provided in Air Space. It is divided around the world in navigation regions which include several countries. Also each country divides its air space in Flight Information Regions.

Air Space is divided upright in inferior and superior air space. Inferior Air Space is conformed from the land or water surface up to but not including 20,000 ft. The Superior Air Space is established from 20,000 ft. upwards without a limit.

The Flight Information Regions are divided in: Controlled Air Space and Non-controlled Air Space. To be able to fly in the Controlled Air Space it is required to have a Flight Plan while in the Non-controlled Air Space control services only inform about the flights they have knowledge of.