Cosmic Penguin
Geek Penguin in GTO
It's make-or-break o'clock for India's rocket industry as their self-built liquid hydrogen rocket engine (but see below; it's basically a copy of a similar Russian engine) gears up for take no. 2 after the first try failed more than 3 years ago - and perhaps the final chance to rescue one of their workhorse space launchers from its infamous reputation as perhaps the most unreliable rocket in service worldwide today.
The 8th GSLV (Geosynchronous Satellite Launch Vehicle) rocket is now on the launch pad at the main Indian spaceport at Sriharikota, near the southern city of Chennai, waiting for launch at 11:20 UTC (4:50 pm local) today. It will carry GSAT-14, a 2 tonne communication satellite into geostationary transfer orbit.
GSLV is (in)famous in the rocketry arena as perhaps the most unreliable satellite launcher in service today - of the 7 launches up till today, only 2 were completely successful, plus 1 more resulting in a lower orbit than planned and still salvageable. Another launch put a satellite into a useless orbit and the other 3 simply failed to reach orbit. This record is even worse than the likes of Falcon 1 and North Korea's satellite launcher - and is quickly approaching the "legendary" Europa. :facepalm:
Here's the full record of GSLV's history:
1. April 18, 2001 - GSLV flight D1 with GSAT-1 - originally reported as full launch success, later orbit apogee determined to be 4000 km short, satellite used up all fuel while circularizing its orbit and cannot be used in its planned mission
2. May 8, 2003 - GSLV flight D2 with GSAT-2 - full launch success
3. September 20, 2004 - GSLV flight F01 with GSAT-3 - full launch success
4. July 10, 2006 - GSLV flight F02 with INSAT-4C - one strap-on booster engine failed right at liftoff, rocket veered off course at T+53 seconds and broke up by T+100 seconds
5. September 2, 2007 - GSLV flight F04 with INSAT-4CR - originally reported as launch success, orbit apogee later found to be 4000 km lower than planned with the satellite able to make up the shortfall with some loss of usable life
6. April 15, 2010 - GSLV flight D3 with GSAT-4 - first flight with Indian built hydrogen upper stage engine, which failed just after ignition at T+5 minutes due to fuel booster pump malfunction
7. December 25, 2010 - GSLV flight F06 with GSAT-5P - rocket broke up at T+47 seconds after electrical connectors broke at Max-Q, probably due to the use of larger fairings and higher upper stage propellant load than previous launches (
The ongoing problems with GSLV may be connected with its very strange design - while the rocket can only launch 2.3 tonnes to GTO (roughly the same as Ariane 2 and just a bit higher than the Delta II), the rocket is a mix and match of solid motors, hypergolic engines and an interestingly designed cryogenic upper stage engine.
The first stage consists of a solid main stage (inherited from the earlier PSLV, with 4.7 MN thrust) with 4 liquid boosters (using hypergolic engines that are licensed-built variants of the Viking engine that powered the lower stages of Ariane 1-4) strapped together that separates as one piece. Strangely, the solid motor burn out at 100 seconds, 50 seconds before the strap-ons does - a design not seen anywhere else in the world!
The second stage is similar to the PSLV second stage and uses a similar engine that power the boosters, burning for 150 seconds.
All eyes will of course focus on the cryogenic upper stage, which is flying for the second time with a self-built engine. This engine is more or less a self-made copy of the Russian RD-58 engine, which was designed to power the upper stages of several planned variants of the N-1 rocket, ending up never flown and later sold to India to power the first few GSLV rockets. Interestingly, this 70 kN thrust engine is powered using the advanced stage combustion cycle, which means the engine has very high efficiency, at a cost of very high internal pressure and thus little margin for weak materials and parts.
No wonder that the rocket has a tendency to undergo "Brownian motion" :facepalm: - there's just too many things that have to go right for a launch to be successful, especially considering that every country that has developed a liquid hydrogen / liquid oxygen powered rocket engine faced teething troubles well after putting them into actually use! There's tremendous pressure for this launch to succeed - but will the stars be aligned? We shall see in a few hours..... :uhh:
As for the payload and the launch time-line, I'll defer to ISRO for the details:
Photos, videos and live webcast link to follow very soon..... :tiphat:
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