look news india
When IndiGo’s Airbus A320 aircraft landed on the Udaipur runway in Rajasthan on the afternoon of 27 June 2026, everything seemed absolutely normal to the passengers looking out the window at the beautiful Aravalli hills. But backstage, a huge record had been created in the history of Indian aviation and science. This huge passenger jet was landed safely not with the help of traditional ground radio signals present on the runway, but with the help of indigenous satellites deployed round the clock in space thousands of kilometers away over India.
It has become the first large passenger jet in the country to make a commercial landing using India’s indigenous satellite-based navigation system ‘GAGAN’, under the strict monitoring and guidelines of the Directorate General of Civil Aviation (DGCA). Let us understand this entire technology in simple language from the perspective of an expert reporter, how it works and why this historical milestone is very special for India.
What is ‘GAGAN’ system and how does the pilot get help from space?
The full name of GAGAN is ‘GPS Aided GEO Augmented Navigation’. This very modern and complex system has been jointly developed by the Indian Space Research Organization (ISRO) and the Aviation Authority of India (AAI) after years of research. Gagan’s powerful signal reaches the cockpits of aircraft directly through ISRO’s GSAT-8 and GSAT-10 communication satellites present in space.
In very simple words, you can understand it like a ‘super class teacher’ or ‘guide’ who sits in the sky and checks the working of the American GPS every second. By immediately correcting even minor errors or distance errors in GPS signals, it transmits absolutely accurate and error-free information to the pilot’s receiver. When an aircraft is landing in dense fog or bad weather, the sky shows it the exact path to the runway as precise as a needle.
Traditional radio networks vs Gagan: A boon for small town airports
Generally, ground-based ‘Instrument Landing System’ (ILS) i.e. Ground Radio Beam Network is used to land planes safely at international airports of big cities like Delhi, Mumbai. This system sends invisible waves (radio signals) from the ground to the pilot and tells him the right way to approach and touch down on the runway. But this traditional ground system is very expensive and it is not possible to install and maintain it at every small or regional airport in hilly areas (like Shimla, Kullu or North-Eastern states).
In contrast, the Gagan system does not require any expensive frills or towers worth crores of rupees on the ground. With the help of satellites present in the space, it gives accurate guidance to the pilot both left-right (horizontal) and up-down (vertical), due to which night landing of big aircraft and landing in bad weather even at airports of small cities will become very easy.
What is the difference between GAGAN and NavIC? People often get confused
Often people consider GAGAN and NavIC to be the same, but from the scientific point of view, both of them are completely different from each other and work for different purposes. NAVIC (Navigation with Indian Constellation) is a completely independent and indigenous positioning network of India, which finds its own way – just like America’s GPS or Russia’s GLONASS works.
On the other hand, Gagan itself is not a new navigation network nor does it create a new path. The main work of GAGAN is to closely examine the signals received from GPS only and only, remove their technical shortcomings and make them as reliable and accurate as possible for the safety of civil aviation.
How does Gagan overcome the shortcomings of GPS for a 70 ton airplane?
The typical GPS in our smartphones can have an error of up to a few meters (5 to 10 meters), which is fine for driving on the road or finding a restaurant; But it is not at all safe to land a heavy 70 tonne airplane on the runway with zero visibility and dense clouds. Due to the Earth’s upper atmospheric layer (Ionosphere) present over India, GPS signals often slow down or get distorted, due to which there is a risk of showing the wrong location.
To fix this completely, ISRO has built 15 highly sensitive ground reference stations (INRES) across India, whose geographical location is fixed to the centimeter. These stations detect GPS errors in real-time, the Indian Master Control Center (INMCC) creates a mathematical formula to correct it and immediately sends it to the plane’s receiver through satellites. The most important thing is that if the signal cannot be trusted due to some technical fault, then this system also gives a warning alert (Time-to-Alert) to the pilot within just 6 seconds.
India joins America-Europe club: Why is ‘Gagan’ the world’s most advanced system?
With this historic successful landing in Udaipur, India has joined the elite club of those select and few countries in the world which have their own Satellite Based Augmentation System (SBAS). Currently America uses WAAS (Wide Area Augmentation System) for this, Europe has its own EGNOS and Japan uses MSAS technology.
But amidst all this, India’s Gagan system is considered to be the most unique and advanced in the world because it has become the only certified system in the world that works with 100% accuracy even in the extremely difficult, turbulent and rapidly changing skies of the Equatorial Zone. With the arrival of Gagan, the meaning of security in the Indian civil aviation sector has completely changed.