NEW DELHI: The Directorate General of Civil Aviation has ordered airlines to track planes on a real-time basis from takeoff to landing, following a report from the Malaysian government recommending such measures after the disappearance of Malaysia Airlines flight MH 370.The local aviation regulator has asked air transport operators to use either the onboard Aircraft Communications Addressing and Reporting System (ACARS) or Automatic Dependent Surveillance – Broadcast (ADS-B) for real-time tracking. Airlines have to ensure that the two devices are in working condition before every departure.“Operators have also been advised to devise a procedure for effective tracking of the aircraft while flying over areas where there is no coverage of ACARS/ADS-B,” the DGCA said in a statement.ET had reported on March 31 that the DGCA had mandated airline crew to be trained in ACARS as it was working towards mandatory real-time flight tracking using the system.ACARS is like an on-board computer which collects large chunks of information about aircraft health and performance and sends digital messages to a ground-level control centre, the airline and even the engine manufacturer.Just before takeoff, an automatic message is triggered from the ACARS on the aircraft to the operations control centre which records the departure time. A similar process happens when the flight lands.Apart from technical and location details of an aircraft, ACARS can give information on weather, medical emergencies and catering requirements.During the past five years, there had been two occasions when large commercial transport aircraft went missing and their last positions were not accurately known, the DGCA said.“While commercial air transport aircraft spend considerable amount of time operating over remote areas, there is currently no international requirement for real-time tracking of the aircraft. This uncertainty resulted in significant difficulty in locating the aircraft in a timely manner in both cases. Such incidences, as well as the recent Malaysian tragedy have prompted the DGCA to take necessary action,” it said.The ongoing search for flight MH 370, a Boeing 777-200ER with 239 people on board that went missing on March 8, is the longest in modern aviation history. The disappearance of the aircraft after it lost contact less than hour into its flight from Kuala Lampur to Beijing, triggered a multi-national search operation but nothing has been found till now. A report from Malaysia’s Ministry of Transport had recommended UN body International Civil Aviation Organisation to develop standards for real-time aircraft tracking.In India, IndiGo, GoAir and Air India have ACARS on all their planes. Jet Airways uses ACARS on its wide-bodied planes and a Boeing programme called Airplane Health Management for tracking other planes. SpiceJet doesn’t have ACARS yet but an airline insider said the airline has systems in place for flight tracking and will be able to comply with the DGCA safety circular.