GSLV D3 Launch By India, Today

On Thursday, India becomes only the 6th country in the world - after the US, Russia, Europe, Japan and China - to possess its own cryogenic engine technology in satellite research.

The countdown for the lift-off of GSLV-D3, a geo-synchronous satellite launch vehicle powered by India's first indigenous cryogenic engine, began at 11:27 am on Wednesday, 14 April, at the Satish Dhawan Space Centre in Sriharikota (Andhra Pradesh). The launch will take place on 15 April at 4:27 pm.

GSLV is a launch system developed by ISRO (Indian Space Research Organization), in order to launch the INSAT series of satellites into geostationary orbit (thus making these satellites appear motionles in the sky, since they revolve round the earth as fast as the earth rotates on its own axis).

Cryogenic liquid is liquefied gas at very low temperature, and is the fuel required to put heavy communication satellites weighing more than 2 tonnes into orbit (GSO). It took India over 15 years to develop this technology, thanks to sanctions imposed by the US on Indo-Russian tech-transfer deals that prevented cutting-edge technology from being used by India.

The GSLV-D3 vehicle is 49 metres tall, as high as a 25-storey building, and weighs 419 tonnes. It is a 3-stage rocket. The core first stage is powered by solid propellants. Around this core stage are 4 strap-on motors that are powered by liquid propellants. The 2nd stage again uses liquid propellants, and the 3rd upper stage is propelled by the indigenously made cryogenic engine.

The 2nd stage and the 4 strap-on booster motors will be filled with liquid propellants during the 29-hour countdown. The filling of the cryogenic engine with liquid hydrogen and liquid oxygen will continue till almost the end of the countdown to prevent loss of cryogenic fluids due to evaporation. There will also be mandatory checks of the vehicle and charging of the batteries in both the rocket and the satellite, during this countdown.

After a 17-minute flight, the satellite will be put into orbit.