With GSLV success, Isro joins exclusive space club

Denied Cryogenic technology in 1993, space agency undertook long, massive development effort

Continuing its success spree, Indian Space Research Organisation (Isro) on Monday launched its heaviest satellite yet, the G-SAT 19, into Geo-Transfer Orbit (GTO) onboard the agency’s heaviest launcher to date — the GSLV Mk III — from the Satish Dhawan Space Centre, Shar, Sriharikota in Nellore district, catapulting India into the small league of space-faring nations that are capable of launching four-tonne class satellites.

It was the GSLV Mk III’s first orbital mission, with an indigenous cryogenic stage.

With two muscular solid strap-on boosters, a large liquid power stage and a homegrown cryogenic upper stage, the 640-tonne three-stage Mk III rocket took off majestically into the clear skies from the second launch pad at SDSC exactly at 5.28 pm as per schedule as those assembled to watch the launch, from the scientists at the launch centre to the media and people far outside the space centre, cheered. A little more than 16 minutes later, it had injected the 3.2-tonne GSAT 19 satellite into GTO.

The satellite will be later moved into its allotted Geostationary orbit by firing its engines.

A beaming Isro chairman A.S. Kiran Kumar said it was a historic day and congratulated team Isro.

“The mood is now upbeat inside the Mission Control Centre, but there were butterflies in the stomach until the cryogenic stage ignited, although we were confident of success because of the 199 tests we conducted on the stage before launching,” Mr Kiran Kumar told journalists.

From the days of launching sounding rockets in the 1960s, India has travelled a long and difficult path to launch heavy launch capability with the GSLV Mk III rocket and achieve self-reliance in satellite launch vehicle technology.

Cryogenic rocket technology was denied to India in 1993, and Isro scientists and engineers had to undertake a twodecade long effort to build indigenous capability, learning the hard way.

Satellite Launch Vehicle -3 (SLV-3) was the first launch vehicle developed indigenously by India. It was a four-stage vehicle and all the stages used solid propellants.

The successful launch of Rohini RS-1 satellite by SLV-3 in 1980 enabled India to join the select club of six countriesUnited States, former USSR, France, Japan, China and Britain- with capability to launch satellites on their own.

SLV-3 was followed by the Augmented Satellite Launch Vehicle (ASLV), which facilitated the development and testing of advanced technologies essential for large launch vehicles. All the four stages of ASLV as well as its two strap-ons used solid propellants.

The Polar Satellite Launch Vehicle (PSLV) was India’s third generation launch vehicles, and the first to be powered by liquid stages. The first and third stages as well as the strap-ons of PSLV are solid whereas its second and fourth stages run on liquid fuel. The need for a heavier launch vehicle was felt during the 1990s to meet the country’s requirement for heavier communication satellites with large numbers of transponders.

That led to the design of the Geosynchronous Satellite Launch Vehicle series, the fourth generation of Indian launch vehicles. These rockets use solid, liquid and cryogenic engines. The GSLV Mk III’s success in its very first flight is the latest feather in Isro’s cap.