GPS-Aided GEO Augmented Navigation (GAGAN) is an implementation of a regional satellite-based augmentation system (SBAS), developed by India.
Aviation regulator Directorate General of Civil Aviation (DGCA) had late last year convened a consultation meeting with all stakeholders on the issue.
Sources say a mandate is now being prepared, which would make it compulsory for all domestic airlines to induct only those aircraft in the fleet which are equipped with GAGAN air navigation system.
The combined fleet strength of Indian carriers including regional ones currently stands at over 450 planes.
According to Boeing's 2016 India Current Market Outlook (CMO), released last year, Indian airlines would require 1,850 new airplanes, valued at USD 265 billion over the next 20 years.
Significantly, three domestic carriers -- IndiGo, SpiceJet and GoAir-- have placed orders with both Boeing of the US and European aviation major Airbus for large number of aircraft which are to be inducted over the next few years.
At present, majority of the aircraft in the country are not equipped with a particular type of GPS receiver compliant for satellite-based augmentation systems like GAGAN. These receivers help in precision guidance for landing at airports using satellite signals.
According to a senior AAI official, so far only four SpiceJet and two GoAir planes have the GAGAN system while a few non scheduled-charter planes are also GAGAN-compliant.
The National Civil Aviation Policy, announced by the government in 2015, made it mandatory for all aircraft being registered in India from January 1, 2019 to be GAGAN-enabled.
Jointly developed by Indian Space Research Organisation (ISRO) and Airports Authority of India (AAI), at an investment of Rs 774 crore, the new system offers seamless navigation to the aviation industry.
GAGAN system, which is said to make airline operations more efficient and cut costs as it reduces separation between aircraft with increase in air safety and fuel efficiency, was officially launched by Civil Aviation Minister Ashok Gajapathi Raju in July, 2015.
However, for availing the system, airlines are required to make their fleet system compliant which entails huge investments.
Sources say that while smaller aircraft like ATRs and Bombardiers which are currently in Indian carriers' fleets are already equipped with such a system, bigger planes like Airbus A320, A330, Boeing 737, B777 and B787s, among others, are not.