ISRO Flags Off Core Liquid Stage of LVM3 for Sriharikota Mission
In a significant step toward another milestone in India's space program, the core liquid stage (L110) of the LVM3 launch vehicle was officially flagged off on January 17, 2025. The event took place in the presence of Secretary of the Department of Space (DOS) and Chairman of ISRO, along with the Directors of Vikram Sarabhai Space Centre (VSSC), Satish Dhawan Space Centre (SDSC-SHAR), and ISRO Propulsion Complex (IPRC). The stage is now en route to the launch complex at Sriharikota for integration into its upcoming mission.
This marks the 10th L110 liquid stage successfully integrated at the ISRO Propulsion Complex in Mahendragiri. The L110 stage is a critical component of ISRO’s LVM3 (Launch Vehicle Mark-3), India’s most powerful rocket, often referred to as its "heavy-lift" vehicle. It is designed to handle the heaviest payloads and is a cornerstone for India's ambitions in commercial satellite launches and interplanetary missions.
Key Features of the L110 Liquid Stage
The L110 stage is powered by two indigenously developed Vikas engines, which have been a workhorse of ISRO's liquid propulsion technology. The stage uses 110 tonnes of hypergolic propellants — unsymmetrical dimethylhydrazine (UDMH) as fuel and nitrogen tetroxide (N2O4) as the oxidizer. This powerful combination generates the necessary thrust to lift the LVM3 and its payloads into space.
Originally designed and developed by the Liquid Propulsion Systems Centre (LPSC), the L110 stage plays a pivotal role during the initial phase of flight, ensuring a smooth transition to the cryogenic stage for orbit insertion.
A Commercial Milestone: The AST & Science Partnership
This particular mission involving the L110 stage is part of a commercial agreement between NewSpace India Limited (NSIL), the commercial arm of ISRO, and AST & Science, LLC. The mission will deploy AST & Science's BlueBird Block 2 satellite into orbit. The collaboration highlights ISRO's growing role in the global commercial space industry, leveraging its reliable and cost-effective launch capabilities to attract international customers.
AST & Science’s BlueBird Block 2 satellite is a part of a larger constellation aimed at delivering low-latency broadband communication services across the globe. The satellite's deployment using the LVM3 rocket not only demonstrates the capability of India's launch vehicles but also reinforces its standing as a preferred launch partner for commercial satellite operators.
LVM3: India’s Heavy-Lift Workhorse
The LVM3, previously known as the GSLV Mk-III, has earned its reputation as ISRO’s flagship rocket. It can carry payloads of up to 4 tonnes to Geostationary Transfer Orbit (GTO) and up to 10 tonnes to Low Earth Orbit (LEO). Its reliability and performance have made it a key vehicle for both national missions, such as Chandrayaan-2, and commercial launches.
The LVM3 consists of three stages:
- S200 Solid Rocket Boosters: These provide the initial thrust during liftoff.
- L110 Liquid Stage: Powered by twin Vikas engines, this core stage takes over after the boosters separate.
- C25 Cryogenic Upper Stage: The final stage, fueled by liquid hydrogen and liquid oxygen, places payloads into their designated orbit.
ISRO’s Growing Commercial Success
The commercial agreement for this mission underscores ISRO's expanding role in the global space economy. NSIL, which oversees ISRO's commercial activities, has been instrumental in marketing India's space capabilities to international clients. The deployment of AST & Science’s satellite using the LVM3 demonstrates the confidence global players have in ISRO’s technology and expertise.
This mission adds to the growing list of achievements for LVM3, which has previously launched multiple satellites under commercial contracts, including successful missions for OneWeb and other international clients. With this flag-off, ISRO is poised to further cement its position as a reliable, affordable, and cutting-edge player in the competitive commercial launch market.
The Road Ahead
As the L110 liquid stage makes its way to Sriharikota, preparations for the mission will ramp up at the SDSC-SHAR launch complex. The integration of the L110 stage with other components of the LVM3 rocket will be closely monitored to ensure a flawless mission.
This mission serves as a reminder of ISRO’s commitment to advancing indigenous technology while actively contributing to global space initiatives. The successful completion of this launch will not only add another feather to ISRO’s cap but also strengthen its reputation as a preferred partner for commercial space ventures worldwide.
