Bengaluru: The Launch Vehicle Mark 3 (LVM3) is ISRO’s newest medium-heavy lift launch vehicle, the heaviest rocket currently in use by the space agency. Formerly called the Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk III), the rocket is designed to mainly launch satellites into geostationary orbit at 35,000km.
On Sunday, in its first commercial mission, the LVM3 launched 36 satellites belonging to OneWeb’s constellation in five staggered phases into their designated orbits. The launch was facilitated through ISRO’s commercial arm, NewSpace India Limited (NSIL), and came about after Russia denied launch services because of Western sanctions.
At 6 tons, this was the heaviest payload carried by an Indian launch vehicle. At 0142 hrs IST, ISRO announced that the mission was a success.
With the successful complex insertion sequence, after years of test flights and hiccups and a national lunar mission in its pocket, India’s largest and heaviest rocket is now in the market to ferry international customer satellites into space.
The development for the GSLV Mk III began in the early 2000s, along with the development of the cryogenic upper stage, which ISRO has been trying to develop to reduce reliance on the currently-used Russian design. The failure of the upper stage to ignite in consecutive flights in the GSLV MkII led to the first test flight of GSLV MkIII being delayed.
The rocket’s first experimental flight (also known as developmental or test flight) was initially scheduled for the early 2010s, but was pushed to make time for the Mars Orbiter Mission which launched in 2013.
The static fire tests for the rocket and its boosters were conducted in 2010, 2011, and 2015. The human-rated variant of the rocket, which is being developed for the Gaganyaan programme, also underwent static fire tests this year.
The cryogenic upper stage was also tested successfully in 2017.
The maiden suborbital test flight of the GSLV Mk III was on 18 December 2014 as a test flight with a dummy upper stage. It carried the Crew Module Atmospheric Re-entry Experiment (CARE), a part of the Gaganyaan mission. The first orbital test flight occurred on 5 June 2017, carrying the GSAT-19 and placing it successfully in a 170km orbit. The second orbital test flight on 14 November 2018 placed the GSAT-29 into a geostationary orbit.
The first operational flight of the launch vehicle was on 22 July 2019, with Chandrayaan 2. The 4 tonne payload of this mission was, at the time, the heaviest payload carried by ISRO to orbit.
This Sunday’s successful mission carried a payload of 5,796kg — now ISRO’s heaviest till date.
While the LVM3 was named the GSLV Mk III, it features a suite of improved systems and components over the GSLV Mk II. As a result, the rocket is considered to be in a league of its own, apart from the trusty Polar Satellite Launch Vehicle (PSLV) and the GSLV.
The LVM3 is capable of lifting much heavier satellites than the GSLV Mk II with a bigger cryogenic upper stage and a larger first stage. Both GSLV Mk II and LVM3 are three-stage vehicles, while the PSLV, which launches to low earth polar orbits, is a four-stage vehicle. The GSLV Mk-II can place up to 2,500kg in geosynchronous orbits and up to 5,000kg to low earth orbit. By comparison, the LVM3 can lift 4,000kg to GTO and up to 8,000 kg to LEO.
Currently, SpaceX’s non-human rated Falcon Heavy, a super-heavy lift vehicle, is the heaviest rocket that is operational, only surpassed by the retired Saturn V, which launched Apollo astronauts to the moon.
The LVM3 also has the human-rated variant which will be used for Gaganyaan missions.
The next launch for the rocket is planned for February 2023, yet again launching 36 of OneWeb’s satellites, while June of next year will tentatively see the launch vehicle pushing Chandrayaan-3 to a trans-lunar orbit.
(Edited by Anumeha Saxena)