A MAJOR LANDMARK

IndiGo Becomes First Airline To Use indigenous GAGAN While Landing

     India achieved a major landmark when the Airports Authority of India (AAI) successfully conducted a trial applied the latest technology developed by an indigenous satellite-based augmentation system (SBAS) called GAGAN (GPS Aided GEO Augmented Navigation) at the Kishangarh airport in Rajasthan. India is the first country in Asia Pacific Region to achieve this. The flight was conducted using an ATR-72 aircraft. The IndiGo aircraft flew an aircraft with an Instrument Approach Procedure (IAP) with LPV minima of 250ft, using GAGAN Service.

    GAGAN is an Indian Space-based Augmented Navigation System, jointly developed by AAI and ISRO. While GAGAN is primarily meant for aviation, it will provide benefits to several other segments such as intelligent transportation, maritime, highways, railways, security agencies, telecom, etc. The GAGAN is designed to provide the additional accuracy, availability, and integrity necessary to enable users to rely on GPS for all phases of flight, from en route through approach for all qualified airports within the GAGAN service volume. It will also provide the capability for increased accuracy in position reporting, allowing for more uniform and high-quality Air Traffic Management (ATM). Once fully rolled out, it will make several smaller airports such as those in the North-East capable of having compliant aircraft land in low-visibility scenarios. 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.  It is first such system developed for India and neighbouring countries in equatorial region. It aids during natural disasters like floods and earthquakes by sending messages to affected people.

     The SBAS is a navigation system, which builds on the Global Navigation Satellite Systems (GLONASS), and adds to the accuracy and integrity of these navigation tools. For aircraft operators, both civilian and military, it means that pilots can land aircraft at smaller airports and airstrips using navigation guidance without expensive instrument-based landing systems being installed on the ground. While the SBAS developed by the US, Japan, Europe and India are already operational, there are several more under development. These include China’s BeiDou SBAS, South Korea’s Korea Augmentation Satellite System (KASS), Russia’s System for Differential Corrections and Monitoring (SDCM), and the Southern Positioning Augmentation Network (SPAN) of Australia and New Zealand. 

    GPS (Global Positioning System) signals are not always pin-point accurate and are susceptible to factors and disturbances such as ionospheric interference, the location of the moving vehicle, and even the functioning of the GPS satellite, signal availability, etc. Many advanced countries have their own localised solutions to such problems. Using a technology known as the Satellite-Based Augmentation System (SBAS), they correct the errors in GPS signals and feed the corrected signals to the moving vehicle (GPS user), thus enabling precise navigation. 

    It must be noted that India's Aviation Sector Regulator issued a mandate for all aircraft registered in India after July 1, 2021, to be fitted with GAGAN equipment. Gagan Satellite Based Augmentation System (SBAS) user equipment is interoperable with all international SBAS systems-WAAS (American), EGNOS (European) & MSAS (Japanese). Once fully adopted in India’s civil aviation sector, GAGAN is expected to modernise the airspace, reduce flight delays, save fuel, and improve flight safety, as pilots using Gagan need not take a circuitous, non-precise approach for landing. Instead, they can precisely land directly into Tier 2 and Tier 3 airports using the accurate data provided by Gagan.