text: Air traffic control (ATC) is a service provided by ground-based controllers who direct aircraft through controlled airspace using aviation technology.
  The primary purpose of the air traffic control technology worldwide, including Nigeria, is to prevent aircraft collisions.
  Air traffic controllers are people trained to maintain safe, orderly and expeditious flow of air traffic in the global air traffic control system. The position of air traffic controller is one that requires highly specialised knowledge, skills, and abilities.
  Air Traffic Control: How do they work?
  With the aid of modern communication technology, controllers guide aircraft as they take off or land and taxi to or from the gate. Their primary function is to separate aircraft on the airport surface. Such control takes place from air traffic control towers at airports.
  Controllers from the take-off facilities guide airplanes flying at high altitudes through large sections of airspace. As aircraft fly across the country, pilots talk to controllers in successive en route facilities.
  In Nigeria, there are presently 275 trained Air Traffic Controllers, working with Nigerian Airspace Management Agency (NAMA) in many areas of Air Traffic Control, according to information by the government aviation agency. In Nigeria, these Traffic Controllers man the nation’s airspace with 25 other retired Air Traffic Controllers engaged on contract basis.
  According to National Bureau of Statistics (NBS), the Nigerian aviation industry carried 3,810,758 air traffic passengers in the last quarter of 2015.
  We can now imagine how many lives these air traffic controllers save every year just with the aid of this communication technology system.
  Air Traffic Control Services:
  - Air traffic advisory service. A service provided within advisory airspace to ensure separation, in so far as practical, between aircraft which are operating on Flight Information Region (FIR) flight plans.
  - Alerting service. A service provided to notify appropriate organisations regarding aircraft in need of search and rescue aid, and assist such organisations as required.
  - Flight Information service. A service provided for the purpose of giving advice and information useful for the safe and efficient conduct of flights.
  According to Captain Chesley Sullenberger, a retired U.S. Airways pilot and a Safety and Aviation expert, there are fixed required horizontal and vertical separation distances and heights that air traffic controllers must maintain between aircraft at various stages of their flight.
  The air traffic controllers make sure that aircraft keep those distances. That is why the controllers need to observe every bit of movement of the aircraft until it is safely landed. The idea behind air traffic control is that of people, technology and system working together to keep the airspace safer.
  Although with latest technology, every aircraft has a traffic collision avoidance system (TCAS) which monitor the airspace around an aircraft for other aircraft equipped with a corresponding TCAS. This is independent of air traffic controllers and is designed to warn pilots and prevent midair collisions.
  Air traffic controllers also monitor radar screens to track aircraft as they fly. As aircraft fly over radar sites, the data from those radars are communicated digitally through telecommunications lines to controllers hundreds or even thousands of kilometers away.
  Even after the landing of the aircraft, the air traffic controllers are busy with safety works. The controllers are responsible for all movements and for making sure that not only aircraft but airport vehicles are doing what they are assigned to do on specific routes.
  “Much of the risk of collision occurs on the ground, not in the air” Sully says. “It may be an aircraft or an airport vehicle that is not where they’re supposed to be. They may be too close to an active runaway. ATC has to deconflict these movements,” he says.
  The global aviation industry today has newer technology for air traffic control that uses both radar and satellite-based technology and Nigeria has not been left out in the adoption of this new technology.
  As part of the Federal government’s effort to move along with the stream of technology, Engineer Emma Anasi, Ag. Managing Director of the Nigerian Airspace Management Agency (NAMA), says the agency wants to ensure a speedy completion of the Aeronautical Information Services (AIS) Automation project.
  While disclosing this during this year’s World AIS Day celebration, Anasis says that in spite of initial challenges traceable to lack of funding and other technicalities, the project is back on course.
  According to him, AIS is the “live-wire of any air navigation system, as it ensures the safety, efficiency and regularity of air navigation through the exchange of accurate, timely and reliable information to airspace users.’’
  The first phase of automation is to become fully operational at 11 stations nationwide by this year, and the ongoing global migration from terrestrial-based navigation to satellite-based navigation needed a high level of accuracy and integrity of data needed for safety, efficiency and economy of flight operations.
  Nigerian Airspace Management Agency (NAMA) was established by the Act of Parliament No. 48, commencement date of 29th may 1999, as Air Navigation Service Providers (ANSP) in the country. Its mandate is to provide safe, efficient, effective and economic Air Navigation Services to airspace users, through deployment of new technologies and dedicated workforce.