In pics: India's heaviest rocket GSLV-MK III to blast off today at 5.28 pm

India's heaviest rocket, the GSLV-MK III, will blast off into space carrying the GSAT-19 satellite from Sriharikota today at 5.28 pm. 

The Indian Space Research Organisation's (Isro's) Geosynchronous Satellite Launch Vehicle Mk III (GSLV-Mk III), nicknamed 'Fat Boy', can launch a four-tonne communication satellite into a higher orbit than previous launch vehicles. 

More significantly, the rocket also has the potential to carry a ten-tonne capsule for a manned mission to space.

In its first developmental flight, the GSLV-MK III-D1 will carry communication satellite GSAT-19, which weighs 3,136 kg, as it blasts off from the second launch pad at the rocket port in Sriharikota in Andhra Pradesh.

Another view of the fully integrated GSLV Mk-III-D1 carrying GSAT-19 at the second launch pad. Photo: Isro
 

The GSLV-MK III-D1 is a three-stage vehicle with two solid motor strap-ons, a liquid propellant core stage and a cryogenic stage called C25.

Isro has used a gas combustor cycle in the third stage, which is powered by CE-20 — a homegrown design that has been developed by the space agency's Liquid Propulsion Systems Centre in Mahendragiri.  

Frontal view of the fully integrated GSLV-Mk III-D1 carrying GSAT-19 at the second launch pad. Photo: Isro
 

The massive first stage, along with the strap-on boosters, weighs 610 tonnes and comprises multiple engines all firing nearly simultaneously. It is the second stage which is an altogether new animal, it is a novel Indian cryogenic engine that weighs about 30 tonnes.

Panoramic View of GSLV-Mk III-D1 being moved to second launch pad. Photo: Isro
 

The new cryogenic engine is being tested on a fully functional rocket for the first time. It is the development of this technology, which uses liquid oxygen and liquid hydrogen as propellant, that took more than 15 years for Isro to master.

Payload fairing with GSAT-19 is being integrated. Photo: Isro

C25 Cryogenic Stage at the Stage Preparation Facility. Photo: Isro

S200 Strap-ons integrated with Core L110 Liquid Stage. Photo: Isro

L110 Liquid Stage at Stage Preparation Facility. Photo: Isro

GSAT-19 carries Ka/Ku-band high throughput communication transponders.

Besides, it carries a geostationary radiation spectrometer payload to monitor and study the nature of charged particles and the influence of space radiation on satellites and their electronic components.

GSAT-19 satellite undergoing a test at ISITE Bengaluru. Photo: Isro

GSAT-19 also features certain advanced spacecraft technologies, including miniaturised heat pipe, fibre optic gyro, micro electro-mechanical systems accelerometer, Ku-band TTC transponder, as well an indigenous Lithium-ion Battery.