Q. GPS-Aided Geo Augmented Navigation (GAGAN) uses a system of ground stations to provide necessary augmentation. Which of the following statements is/are correct in respect of GAGAN?
- It is designed to provide additional accuracy and integrity.
- It will allow more uniform and high quality air traffic management.
- It will provide benefits only in aviation but not in other modes of transportation.
Select the correct answer using the code given below. (UPSC Prelims 2025)
Answer:
I and II only
Notes: The correct answer is
[D] I and II only. GAGAN is a Space Based Augmentation System (SBAS) jointly developed by the Indian Space Research Organisation (ISRO) and the Airports Authority of India (AAI).
- Statement I (Correct): GAGAN is designed to provide additional accuracy and integrity to the standard GPS signals. By using a network of ground stations (Reference Stations) to calculate differential corrections and monitoring the "health" of GPS satellites, it ensures that navigation data is precise enough for safety-critical tasks.
- Statement II (Correct): One of the primary objectives of GAGAN is to modernize Air Traffic Management (ATM). It allows for more direct flight paths, reduces fuel consumption, and enables aircraft to land at airports with better safety margins even in poor weather, leading to a more uniform and high-quality traffic flow across the Indian Flight Information Region (FIR).
- Statement III (Incorrect): While GAGAN is primarily optimized for aviation (certified for "Approach with Vertical Guidance"), its benefits are not limited to aviation. It provides high-accuracy positioning for various other sectors, including maritime navigation, railways (for unmanned level crossings), surveying, precision agriculture, and telecommunications.
The system works by using three geostationary satellites—GSAT-8, GSAT-10, and GSAT-15—to broadcast correction messages to users over a wide geographical area covering India and neighboring regions.