GPS Aided GEO Augmented Navigation (GAGAN) is a step by the Indian Government toward initial Satellite-based Navigation Services in India. It is a system to improve the accuracy of a global navigation satellite system (GNSS) receiver by providing reference signals.
GAGAN is used to provide lateral and vertical guidance when an aircraft is approaching a runway for landing. Its precision is especially useful at small airports where the instrument landing system (ILS) has not been installed.
For the first time in the history of the Indian aviation industry, IndiGo became the first airline in the country to land aircraft using the indigenous navigation system GAGAN. India is the first country in Asia Pacific Region to achieve this.
The Airports Authority of India (AAI) and the Indian Space Research Organization (ISRO) have collaborated to develop the GPS Aided Geo Augmented Navigation (GAGAN) as a regional Satellite Based Augmentation System (SBAS).
The GAGAN’s goal is to provide a navigation system to assist aircraft in accurate landing over the Indian airspace and in the adjoining area and applicable to safety-to-life civil operations. GAGAN is inter-operable with other international SBAS systems.
GAGAN Payload is now operational. The satellites GSAT-8 and GSAT-10 satellites have the GAGAN payloads. The third payload of the system will be launched with the GSAT-15 satellite which is scheduled for launch in late of 2015.
The total approximate cost of the project is Rs 7.74 billion and is being created in three phases since 2008.
“Using the satellite technology, we will be able to pull an aircraft into the airport, as opposed to the ground radar. That will take a lot of burden off the ATC operators and ground radar. I see that happening in the next three to five years. So that’s one area where we are using satellite technology in civil aviation,”Jyotiradtiya Scindia
GAGAN covers the area from Africa to Australia and has expansion capability for seamless navigation services across the region. GAGAN provides accuracy, availability, and integrity essential for each phase of flight, en route the approach for airports within the GAGAN service volume.
This makes airline operations more efficient and effective, increasing air safety, and fuel efficiency. Further, with vertical guidance at runways, a significant cost will be saved due to the withdrawal of ground aids and the reduced workload of airline crew and air traffic controllers.
GAGAN is the first Satellite-Based Augmentation System in the world which has been certified for approach with vertical guidance operating in the equatorial ionospheric region.