The Airports Authority of India, or AAI, is a public sector enterprise under the ownership of the Ministry of Civil Aviation, Government of India. It is responsible for creating, upgrading, maintaining, and managing civil aviation infrastructure in India. It provides Communication Navigation Surveillance/Air Traffic Management (CNS/ATM) services over the Indian airspace and adjoining oceanic areas. AAI currently manages a total of 137 airports, including 34 international airports, 10 Customs Airports, 81 domestic airports, and 23 Civil enclaves at Defense airfields. AAI also has ground installations at all airports and 25 other locations to ensure the safety of aircraft operations. AAI covers all major air routes over the Indian landmass via 29 Radar installations at 11 locations along with 700 VOR/DVOR installations co-located with Distance Measuring Equipment (DME). 52 runways are provided with Instrument landing system (ILS) installations with Night Landing Facilities at most of these airports and an Automatic Message Switching System at 15 Airports. History The Government of India constituted the International Airports Authority of India (IAAI) in 1972 to manage the nation's international airports while the National Airports Authority of India (NAAI) was constituted in 1986 to look after domestic airports. The organizations were merged in April 1995 by an Act of Parliament, namely, the Airports Authority of India Act, 1994 and has been constituted as a Statutory Body and was named as Airports Authority of India (AAI). This new organisation was to be responsible for creating, upgrading, maintaining and managing civil aviation infrastructure both on the ground and air space in the country. Major ongoing projects AAI's implementation of the Automatic Dependence Surveillance System (ADSS) at Kolkata and Chennai Air Traffic Control Centers, made India the first country to use this technology in the Southeast Asian region thus enabling Air Traffic Control over oceanic areas using satellite mode of communication. Performance Based Navigation (PBN) procedures have already been implemented at Mumbai, Delhi and Ahmedabad Airports. AAI is implementing the GAGAN project in technological collaboration with the Indian Space Research Organization (ISRO). The navigation signals thus received from the GPS will be augmented to achieve the navigational requirement of aircraft. The first phase of the technology demonstration system was completed in February 2008. Organizational structure AAI board consists of a Chairman and five whole time members which are appointed by the central government. Director General of Civil Aviation is an ex-officio member of AAI board. Apart from this,