Tag: GSLV

  • GSLV-F06 launching the GSAT-5P on December 20

    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 16, 2010 as per the time stamp. I’m trying to collect here again all my old writings spread on various blogs.

    I had earlier written about the possible launch date of GSAT-5P as being December 20. This is now confirmed. Yesterday, ISRO posted photos and descriptions [PDF] about the GSLV-F06 and the GSAT-5P.

    A little bit on the satellite. Unlike the satellite it is replacing, the GSAT-5P is a pure communications satellite. It does not have the meteorological payload that INSAT-2E had. The 2310 kg satellite will be placed in a geosynchronous transfer orbit by the GSLV-F06. The satellite with its C-band transponders will provide continuity of telecommunication services.

    The importance of this launch is not because of its payload but rather because of its launch vehicle. The Geosynchronous Satellite Launch Vehicle (GSLV) is a completely new launch vehicle unlike the PSLV, which has now been tried and tested over the years. It is tasked with launching 2-4 tonne class satellites that the PSLV is not designed to handle. The problems facing the programme have been faced by other rockets in its class and are not un-precedented. However, it has been worrying ISRO because it has impacted ISRO’s strive for self-reliant systems. The delay will cause India to fall back on support on Astrium’s Ariane launch vehicles.

    For the technical personnel, such times are uncomfortable. Questions are raised on the personnel’s capability by the management and it is a difficult time for all concerned. However, this is how people learn in rocketry and science. In a recent interview, I was informed that the way the Sriharikota spaceport works right now it is capable of doing only 3-4 launches per year. ISRO has been working to improve this launch rate with its Chairman making the claim in early 2010 that they hoped to do 10launches this year. The same claims have been carried forward to 2011. I wonder if this has impacted ISRO’s ability to test the rocket without a payload or with dummy payloads like SpaceX did. I had raised this question earlier as well when ISRO’s GSLV with indigenous cryogenic engine failed and fell into the Bay with its payload.

    GSLV is a machine with contributions from many people each one providing critical components. The failure of even one component amongst the bunch can lead to the catastrophic results. Before this launch, I have depressed myself a little. I hope and pray for the team of GSLV-F06. Godspeed!

  • India successfully tests its cryogenic upper stage

    Note: I wrote this on my earlier blog hosted as https://blogs.seds.org/pradeep. I recovered the text from the WayBack Machine. This post appeared on November 19, 2007 as per the timestamp. I’m trying to collect here again all my old writings spread on various blogs.

    The third stage of India’s latest satellite launch vehicle, the GSLV is cryogenic. On November 15, 2007, ISRO successfully tested the indigenously built cryogenic rocket engine that will power the GSLV third stage. Till now, India depended on Russia for its cryogenic third stage but the test now allows India to use its own.

    Developed by the Liquid Propulsion Systems Centre and supported by ISRO centres, public and private companies, it’s a milestone worth taking note of.

    The press release describes the rocket as:

    The indigenous Cryogenic Upper Stage (CUS) is powered by a regeneratively cooled cryogenic engine, which works on staged combustion cycle developing a thrust of 69.5 kN in vacuum. The other stage systems include insulated propellant tanks, booster pumps, inter-stage structures, fill and drain systems, pressurisation systems, gas bottles, command block, igniters, pyro valves and cold gas orientation and stabilisation system. Liquid Oxygen (LOX) and Liquid Hydrogen (LH2) from the respective tanks are fed by individual booster pumps to the main turbo-pump, which rotates at 39,000 rpm to ensure a high flow rate of 16.5 kg/sec of propellants into the combustion chamber. The main turbine is driven by the hot gas produced in a pre-burner. Thrust control and mixture ratio control are achieved by two independent regulators. LOX and Gaseous Hydrogen (GH2) are ignited by pyrogen type igniters in the pre-burner as well as in the main and steering engines.

    Congragulations to ISRO for a successful test firing.