Air traffic controllers are the people who expedite and maintain a safe and orderly flow of air traffic in the global air traffic control system. The position of the air traffic controller is one that requires highly specialized skills. Controllers apply separation rules to keep aircraft apart from each other in their area of responsibility and move all aircraft safely and efficiently through their assigned sector of airspace. Because controllers have an incredibly large responsibility while on duty, the ATC profession is regarded around the world as one of the most challenging careers, and can be notoriously stressful depending on many variables (equipment, configurations, weather, traffic volume, human factors, etc.). Having said this, many controllers would cite high salaries and a very large degree of autonomy as major advantages of their jobs.
Air traffic controllers are generally individuals who are well organized, are quick with numeric computations and mathematics, have assertive and firm decision making skills, and possess excellent short-term memory and visual memory abilities. In addition, studies have shown that air traffic controllers generally have a degree of situational awareness that is much higher than the average population. Excellent hearing and speaking skills are a requirement, and trainees undergo rigid physical and psychological testing. In addition they are generally assertive but calm under pressure, and they are able to follow and apply rules yet be flexible when necessary. Air traffic controllers must maintain some of the strictest medical and mental requirements for professions; conditions such as diabetes, epilepsy, heart disease, and many mental disorders, typically disqualify people from obtaining certification. Conditions such as hypertension, while not disqualifying, are taken seriously and must be monitored with medical examinations by certified doctors. Controllers must take precautions to remain healthy and avoid certain medications that are banned for them.
Although local languages are sometimes used in ATC communications, the default language of aviation worldwide is English. Controllers who do not speak this as a first language are generally expected to show a certain minimum level of competency with the language.
Teamwork plays a major role in a controller’s job, not only with other controllers and air traffic staff, but with pilots, engineers and managers.
Area or enroute
Area controllers are responsible for the safety of aircraft at higher altitudes, in the en route phase of their flight. In most nations they are known as "area" or "en route" controllers. Airspace under the control of Area controllers is split into sectors which are 3D blocks of airspace of defined dimensions. Each sector will be managed by at least one Area controller. This can be done either with or without the use of radar: radar allows a sector to handle much more traffic, however procedural control is used in many areas where traffic levels do not justify radar or the installation of radar is not feasible. In the United States, En-Route controllers work at Air Route Traffic Control Centers or ARTCCs. In other countries, area controllers work in Area Control Centers, controlling high-level en-route aircraft, or Terminal Control Centers, controlling aircraft at medium levels climbing and descending from major groups of the airports.
Aerodrome or Tower
Aerodrome or Tower controllers control aircraft within the immediate vicinity of the airport and use visual observation from the airport tower. The tower's airspace is often a 5-nautical-mile (9.3 km) radius around the airport, but can vary greatly in size and shape depending on traffic configuration and volume.
The tower positions are typically split into many different positions such as Flight Data/Clearance Delivery, Ground Control, and Local Control (known as Tower by the pilots); at busier facilities, a limited radar approach control position may be needed.
The roles of the positions are;
- Flight Data/Clearance Delivery: issues IFR flight plan clearances, usually prior to taxi. Unlike the other positions, FD/CD only involves departing aircraft.
- Ground: issues taxi instructions and authorizes aircraft/vehicle movements on the airport except the active runway(s); controllers are not responsible for aircraft movement on ramps or other designated non-movement areas.
- Local (Tower): issues takeoff and landing instructions/clearances and authorizes aircraft/vehicle movements on or across runways.
- Approach: issues instructions to aircraft who are intending to land at the airport. This involves vectoring aircraft in a safe, orderly, and expeditious manner and, if needed, stacking the aircraft at different holding altitudes.