GSLV and its cryogenic stage
In one line: The Geosynchronous Satellite Launch Vehicle is ISRO's three-stage rocket for placing heavy satellites, such as the 2,250 kg NVS-03, into transfer orbits, with an indigenous cryogenic upper stage.
How it is built
For GSLV-F18, the first stage is a solid S139 motor with four liquid L40H strap-ons; the second is the liquid GL40HT stage; the third is the CUS15 cryogenic stage, which burns liquid hydrogen and liquid oxygen. Cryogenic fuels are stored at very low temperatures and extract more energy from each kilogram of propellant, which is why they power upper stages that must reach high orbits. The rocket is about 50 m tall and weighs about 420 tonnes at lift-off.
Why it is in the news
GSLV-F18 is the 20th GSLV flight. GSLV-F15 carried NVS-02 in January 2025; the rocket performed as planned, but the satellite's own thrusters later failed.
Where to go next
- Geostationary and geosynchronous orbits
- NVS series
GSLV and its cryogenic stage in the news
- Explained: Why NVS-03 matters for restoring NavIC, India's own navigation system 30 October 2026
The rocket that lifts them.
- GSLV-F17 launches EOS-05, India's first imaging satellite for geosynchronous orbit 5 September 2026
India's rocket for high orbits.
Previous-year questions on this
- 2017 · GS3 · 10 marks India has achieved remarkable successes in unmanned space missions including the Chandrayaan and Mars Orbiter Mission, but has not ventured into manned space mission, both in terms of technology and…
- 2016 · GS3 · 12.5 marks Discuss India's achievements in the field of Space Science and Technology. How the application of this technology has helped India in its socio-economic development?
- 2018 · Prelims With reference to the Indian Regional Navigation Satellite System (IRNSS), consider the following statements : 1. IRNSS has three satellites in geostationary and four satellites in geosynchronous…