LVM3-M5 mission: How India’s ‘Bahubali’ rocket defied weight limits

India successfully launched its heaviest communication satellite CMS-03, weighing 4,400kg, on Sunday evening from Sriharikota using the LVM3 rocket, affectionately called ‘Bahubali’.

This mission marks a significant milestone in India’s space ambitions, showcasing not just raw power but clever engineering that allows ISRO to punch above its weight despite having less powerful rockets compared to space giants like NASA or SpaceX.

The LVM3 rocket carrying the CMS-03 satellite, also known as GSAT-7R, lifted off at 5.26 pm from the Satish Dhawan Space Centre.

This multi-band communication satellite is designed to serve the Indian Navy for at least 15 years, providing secure telecommunication coverage across the Indian Ocean Region.

ISRO chief V. Narayanan called it a shining example of Atmanirbhar Bharat, emphasising that the rocket is entirely built with Indian technology, including its crucial C25 cryogenic stage. The satellite features strong encryption, wide frequency coverage, and high-capacity transponders that will support naval operations and improve situational awareness at sea.

“What makes this launch particularly interesting is how ISRO managed to lift a satellite that technically exceeds the LVM3’s standard capacity. The rocket normally carries up to 4,000kg to Geosynchronous Transfer Orbit, but this time it lifted 4,400kg, which is about 10 per cent more than its usual limit. However, ISRO hasn’t added any new engines or made physical upgrades to the rocket. Instead, they used smart planning and efficiency to handle the extra weight,” explained space analyst Girish Linganna.

Explaining further, Linganna noted that one can think of it like a truck that normally delivers 10 tonnes of goods to a hilltop warehouse 100km away. When loaded with 11 tonnes, it can only reach a point 70km up the hill. From there, a smaller vehicle must transport the goods the remaining 30 km to the warehouse.

Similarly, the LVM3 doesn’t place CMS-03 at the full GTO height of 36,000km. Instead, it drops the satellite at around 30,000km, and then the satellite uses its own onboard engines and fuel to climb the remaining distance and settle into its final geostationary orbit.

This orbit makes the satellite appear fixed in the sky because it moves at the same speed as Earth’s rotation, completing one orbit in 24 hours. This is why DTH TV dishes always point in one fixed direction.

“This clever approach reflects a larger pattern in ISRO’s mission philosophy. When NASA sent Apollo 11 to the Moon, it took just four days using a direct, powerful trajectory. But India’s Chandrayaan-2 and Chandrayaan-3 took around 40 days, slowly raising their orbits step by step using the spacecraft’s own thrusters. This longer, roundabout path compensates for not having rockets powerful enough to send satellites directly to their destination in one shot. It’s a testament to ISRO’s ingenuity in achieving ambitious goals within resource constraints,” remarked Linganna.

Experts point out that LVM3 has proven its versatility beyond just communication satellites. During the Russia-Ukraine conflict in 2022, when OneWeb, a global satellite internet company, struggled to find launch providers, India stepped in.

Russia had stopped launching for them, and Europe’s Ariane-5 had retired with its replacement not yet ready. ISRO used the LVM3 to launch 72 OneWeb satellites into low Earth orbit around 450km above Earth, carrying payloads exceeding 5,700kg. This proved the rocket could handle different types of missions and orbits, not just the geosynchronous orbit it was originally designed for.

When compared globally, LVM3 occupies a distinct position among heavy-lift rockets. It does not yet rival the sheer payload power of giants such as SpaceX’s Falcon Heavy, China’s Long March 5, or the European Ariane 6, but it exemplifies efficiency and reliability within its capacity range.

Falcon Heavy, for example, can deliver about 63,800kg to LEO and 26,700kg to GTO (Geosynchronous Transfer Orbit), leveraging reusable booster technology to drastically cut costs and turnaround times.

China’s Long March 5 can carry 25,000kg to LEO (Low Earth Orbit) and 14,000kg to GTO, supporting Beijing’s crewed and lunar ambitions.

The European Ariane 6, set to replace Ariane 5, targets capacities around 21,900kg to LEO and 11,500kg to GTO, emphasising dual-satellite deployments and commercial launches. In comparison, LVM3’s 8,000kg to LEO and 4,000kg to GTO place it at the lower end of the heavy-lift spectrum, but within a cost structure that remains significantly more economical than its Western counterparts.

Despite its lower payload, LVM3’s adaptability is a strength. It can conduct complex orbital manoeuvres thanks to its re-ignitable cryogenic stage, enabling multi-orbit missions and interplanetary insertions.

“LVM3’s versatility has been proven in missions like Chandrayaan-2, Chandrayaan-3, and OneWeb satellite launches. While current versions of LVM3 are fully expendable, ISRO has announced plans for its successor, the Next Generation Launch Vehicle (NGLV), which will feature partial reusability and higher payload capacity to close the performance gap with global leaders,” said Srimathy Kesan, the CEO and founder of SpaceKidz India.

Human-rating the LVM3 marks a new era for India’s space programme. The Gaganyaan configuration incorporates rigorous safety upgrades, including the Crew Escape System (CES), redundant electronics, and life-support integration, aligning with international crewed mission standards.

LVM3 gets inducted into special list

This places LVM3 in a select group of rockets qualified or being prepared to carry astronauts, alongside SpaceX’s Falcon 9 (Crew Dragon), Russia’s Soyuz, and NASA’s Space Launch System (SLS).

While the Falcon Heavy and SLS remain unmatched in raw power—SLS Block 1 can lift around 95,000kg to LEO—India’s approach focuses on sustainable development, cost-efficiency, and incremental technological progress.

Recognising these limitations, ISRO is actively working on upgrades. The space agency plans to increase the thrust of the cryogenic upper stage, which accounts for nearly 50 per cent of the velocity needed to reach geosynchronous orbits. The current C25 stage carries 28,000kg of propellant and produces 20 tonnes of thrust. The new C32 stage will carry 32,000kg of fuel and produce 22 tonnes of thrust. Additionally, ISRO is exploring semi-cryogenic engines using refined kerosene and liquid oxygen for the second stage, which could be both more powerful and cheaper than current liquid-propellant technology.

These improvements are particularly important because the LVM3 will carry India’s astronauts in the upcoming Gaganyaan human spaceflight mission. The Gaganyaan crew module and service module together weigh approximately 8,200kg, but since this mission goes to low Earth orbit rather than GTO, the rocket can handle this payload more easily. The LVM3 has demonstrated a strong success record since its first development mission in December 2014, and its fully indigenous technology gives India strategic independence in space access.

Sci/Tech