What Is GAGAN? How IndiGo Landed an Airbus A320 Using India’s Satellite Navigation System
India's aviation sector achieved a major milestone after an IndiGo Airbus A320 became the first commercial passenger jet to complete a landing using GAGAN, India's indigenous satellite-based navigation augmentation system. The aircraft landed at Udaipur on June 27, demonstrating how satellite technology can improve flight safety and reduce dependence on expensive ground-based landing equipment.
India's aviation sector achieved a major milestone after an IndiGo Airbus A320 became the first commercial passenger jet to complete a landing using GAGAN, India's indigenous satellite-based navigation augmentation system. The aircraft landed at Udaipur on June 27, demonstrating how satellite technology can improve flight safety and reduce dependence on expensive ground-based landing equipment.
What Is GAGAN?
GAGAN, short for GPS Aided GEO Augmented Navigation, is a satellite-based augmentation system jointly developed by the Indian Space Research Organisation (ISRO) and the Airports Authority of India (AAI). InterGlobe Aviation Opening Bell Updates: INDIGO Faces Mixed Cues After Recent Rally.
Unlike NavIC, which is India's independent satellite navigation system, GAGAN does not determine an aircraft's location. Instead, it enhances GPS accuracy by correcting errors in GPS signals and ensuring they are reliable enough for aviation operations.
The system transmits correction signals through GSAT-8 and GSAT-10 communication satellites, providing continuous coverage over Indian airspace. DRDO Carries Out Successful Flight Trial of Autonomous Flying Wing Technology Demonstrator in Karnataka’s Chitradurga (Watch Video).
Why Can't Aircraft Rely on Normal GPS?
While GPS works well for everyday navigation, it is not accurate enough for aircraft during landing, especially in poor weather or low visibility.
GPS signals can become distorted while passing through the ionosphere, creating positioning errors. The challenge is even greater over India because of the equatorial ionisation anomaly, where atmospheric conditions frequently affect satellite signals.
GAGAN corrects these errors in real time, allowing aircraft to receive highly accurate and reliable positioning data.
How Does GAGAN Work?
GAGAN uses a network of 15 reference stations across India whose exact locations are known with centimetre-level precision.
These stations constantly compare GPS-based positions with their actual locations. Any detected error is sent to a central processing facility, which calculates corrections and transmits them via geostationary satellites.
Aircraft equipped with compatible receivers automatically apply these corrections during flight. If the system detects unreliable signals, pilots receive an immediate warning.
What Happened During IndiGo's Historic Landing?
The IndiGo Airbus A320 performed an LPV (Localiser Performance with Vertical Guidance) approach while landing at Udaipur.
An LPV approach provides both lateral and vertical guidance similar to an Instrument Landing System (ILS), but without requiring costly ground-based navigation equipment at the airport.
This marked the first time a full-sized commercial passenger aircraft in India successfully completed such a landing using GAGAN.
Why Is This Important for India?
Installing Instrument Landing Systems at every airport is expensive and requires significant maintenance. GAGAN offers a satellite-based alternative that can support precision approaches at many regional airports.
The technology could:
- Improve landing safety during poor visibility.
- Reduce weather-related diversions.
- Lower infrastructure costs for smaller airports.
- Support India's growing regional air connectivity.
- Enable more efficient air traffic management.
The Road Ahead
ISRO designed GAGAN not only to improve landing accuracy but also to optimise flight routes and enhance air traffic management. The system is compatible with similar satellite-based augmentation systems used in other parts of the world, allowing seamless navigation across international airspace.
With IndiGo's successful Airbus A320 landing, GAGAN has moved from a technological capability to a proven operational tool, marking a significant step towards modernising India's aviation infrastructure.
(The above story first appeared on LatestLY on Jun 29, 2026 11:14 AM IST. For more news and updates on politics, world, sports, entertainment and lifestyle, log on to our website latestly.com).