Note: I wrote this on my earlier blog hosted as http://parallelspirals.blogspot.com. I recovered the text from the WayBack Machine. This post appeared on December 24, 2010 as per the time stamp. I’m trying to collect here again all my old writings spread on various blogs.
On Christmas Day, India will launch its GSLV-F06 with GSAT-5P satellite on board. Since December 20, 2010 when the delay in the launch was announced, ISRO has been working with Russian engineers by conducting several tests on the leaked valve in the Russian cryogenic engine.
It has now been ascertained that the launch could go on. It is still not sure if the leak was fixed or whether it was found whether the leak was within acceptable limits. ISRO has just posted a note on its website saying the launch has started.
There have been several mis-leading reports in Western blogs stating that this is the Indian cryogenic engine. This is wrong. This is one of the two spare engines that ISRO obtained from Russia.
The 2310 kg GSAT-5P is the heaviest satellite that an Indian launch vehicle will carry. Hence the cryogenic engine has been uprated. It now carries 15.3 tonnes of fuel as against 12.5 tonnes and has a payload fairing diameter of 4 metres instead of 2.8 metres. This uprating enables the GSLV Mk-I to carry 2310 kg instead of the 1900 kg capability. GSAT-5P itself is to replace INSAT-2E’s services and upgrade television, tele-medicene, tele-education and telephony services.