IndiGo Airbus A320 becomes India’s first passenger jet to land using Gagan satellite navigation system. On June 27, IndiGo Airbus A320 made aviation history when it became India’s first passenger jet to land using Gagan, the country’s satellite-based navigation system.
What is Gagan?
Gagan, which stands for GPS Aided GEO Augmented Navigation, was jointly developed by the Indian Space Research Organisation (ISRO) and the Airports Authority of India (AAI).
The system is supported by the Gagan signal-in-space through ISRO’s GSAT-8 and GSAT-10 satellites. Unlike GPS or NavIC, Gagan does not independently determine location. Instead, it improves the accuracy of GPS signals by correcting errors before the information reaches the aircraft. NavIC acts as India’s independent navigation system, while Gagan acts as an additional layer that augments existing GPS signals.
How does the system work?
Gagan uses 15 precisely surveyed ground stations across the country. These stations compare the actual location with the position reported by GPS.
Any difference is treated as an error. A correction is then calculated and transmitted to satellites located above the equator, which relay the information back to the aircraft. The system also provides integrity information, warning pilots if the navigation data cannot be trusted.
Why is the Udaipur landing important?
The IndiGo aircraft adopted the LPV approach, providing both horizontal and vertical guidance during landing. This approach provides guidance similar to the instrument landing systems used at major airports, but without the need for expensive ground equipment. For India, the successful landing demonstrates how satellite-based navigation can support safe operations, reduce costs and improve connectivity at smaller airports, especially in areas with challenging weather conditions.
