GSLV MK-III is a three-stage heavy lift launch vehicle developed by ISRO. This is the first step towards the unmanned space mission and was flagged-off by ISRO Chairman Dr K Sivan

NELLORE: Indian Space Research Organisation (ISRO) GSLV MK-III rocket has been identified as the vehicle to launch the Gaganyaan Mission and the process for its human rating is in progress.

GSLV MK-III is a three-stage heavy lift launch vehicle developed by ISRO. It has two solid strap-on motors, a core liquid booster and a cryogenic upper stage. It is designed to carry four-tonne class of satellites into geosynchronous transfer orbit (GTO) or about 10 tons to low earth orbit (LEO), which is about twice the capability of the GSLV MK-II.

The two strap-on motors of GSLV MK-III are located on either side of its core liquid booster. Designated ‘S200’, the high-thrust solid propellant strap-on boosters play an important role in the human-rated GSLV MK-III. Each S200 booster carries 205 tonnes of composite solid propellant and their ignition results in vehicle lift-off.

S200s function for 140 seconds. During strap-ons functioning phase, the two clustered Vikas liquid Engines of L110 liquid core booster will ignite 114 sec after lift-off to further augment the thrust of the vehicle. These two engines continue to function after the separation of the strap-ons at about 140 seconds after lift-off.

According to an ISRO statement on Monday, many new design features have been introduced in the hardware in order to human rate the S200 booster. In a fruitful industry collaboration, the first critical booster segment of the motor case with a diameter of 3.2 metre, 8.5 metre in length and weighing 5.5 tonnes has been indigenously developed and delivered by L&T.

This is the first step towards the unmanned space mission and was flagged-off by ISRO Chairman Dr K. Sivan, who is also secretary, department of space. and Jayant Damodar Patil, director and senior executive vice president, defence & smart technologies, L&T, on November 13.