On May 19, GAGAN, the Rs. 774-crore Indian ‘augmentation’ to GPS, beamed its first signals and became fully ready for use.
India becomes the first country to offer satellite-based fine-tuning of GPS in the challenging equatorial region of severe ionospheric variations. GAGAN is built over the US military's location-telling Global Positioning System. It reached fruition on April 21 when it was certified for APV1 — or precision vertical guidance for planes to land safely — according to its co-creator, the Indian Space Research Organisation. An earlier RMV 0.6 certification for en route navigation came in 2013.
Airports Authority of India and ISRO initiated GPS Aided Geo Augmented Navigation over a decade ago to smoothen air traffic in the country.
Officials associated with it say that when airlines fit a GAGAN receiver on planes and use it, fliers can expect shorter air routes and travel time; fuel and other savings for airlines; while airports can cut congestion and manage air traffic better. Its non-aviation spinoffs, too, are said to be enormous.
An AAI official told The Hindu that with the infrastructure ready, the challenge is in ensuring it is used. The government may be urged to make it mandatory for specific aviation users to use GAGAN receivers, starting with smaller, general aviation planes.
As in Europe and the US, it would take a long time to fit Airbus and Boeing planes with the Indian receivers, the official said.
A.S. Ganeshan, Director of ISRO SatNav Programme, said pilots and other users of GPS would now have near-exact, highly reliable and consistent data on position, height from ground and time. The space agency has provided a transponder each on GSAT-8, GSAT-10 and the upcoming GSAT-15 satellites.
Should GPS signals ‘go bad’, an aircraft approaching an Indian airport would now get landing help within six seconds.
To land, it needs a visibility of 4,000 metres or must turn back. With GAGAN signals, even at a 1,000-metre visibility will do, without ILS landing aids.
AAI is tuning up ground systems at Belagavi, Ahmedabad and four other airports and enthusing airlines and receiver-makers to join in.
Passengers can expect shorter travel time, airlines can save fuel, while airports can cut congestion
