Indian Space News and Discussion

[Arun_S]

[url="http://www.telegraphindia.com/1100307/jsp/nation/story_12187878.jsp"]Isro rocket test fails: L110 Core Stage[/url]

OUR BUREAU[left]New Delhi, March 6: A static ground test of a core stage of a new-generation heavyweight rocket for the future, planned by the Indian Space Research Organisation, has failed, the space agency announced today. [/left]

[left]The liquid-fuelled core stage of the GSLV-Mk3 rocket was to fire for 200 seconds during the ground test at Isro’s Liquid Propulsion Systems Centre in Mahendragiri, Tamil Nadu, but was stopped after 150 seconds, Isro sources said. [/left]

[left]India’s existing Geosynchronous Satellite Launch Vehicle rockets can ferry a 2,000kg- class satellite towards a geostationary orbit 37,000km above Earth. The GSLV-Mk3 is expected to carry a 4,000kg-class satellite towards a geostationary orbit. [/left]

[left]The GSLV-Mk3 can also carry a 10,000kg payload into a low-earth orbit — an altitude of about 200km — and is thus viewed as a crucial technology that Isro will need to develop in its bid to launch manned space capsules. [/left]

[left]“The ground test on Friday evening was stopped after engineers detected an unanticipated deviation in one of the parameters being observed during the firing,” an Isro official told The Telegraph. [/left]

[left]While the rocket fires in the static mode, engineers keep track of more than 500 parameters, such as temperatures at various points in the rocket, liquid flow rates and pressure levels, the official said. [/left]

[left]The next static ground test will be conducted after analysis of this data, Isro said. [/left]

[left]The liquid-fuelled stage has 110 tonnes of propellant and is similar to the liquid stages used in Isro’s existing GSLV rockets — only with a greater capacity. In the existing GSLV, it burns for 150 seconds; the GSLV-Mk3 will demand 200 seconds of firing. [/left]

[left]The test was aborted after some “[color="#0000ff"]minor leakage in the command system[/color]”, PTI reported, quoting Isro sources. [color="#0000ff"]It is a “very minor problem” in which a small leak in the command line was detected by a computer, which automatically stopped the test. “There is absolutely no problem with the engine,”[/color] a source said. [/left]

[left]Earlier this year, Isro had successfully conducted ground tests of solid strap-on stages of the rocket. [/left]

[left]

This L110 stage is one that for the first time uses clustered liquid fuel booster engine. This is part of the reson ground test firing of engine is done, and root cause analysis can eb easily done by stopping teh engine and digging out failure modes from that.



Here he is talking of hydraulics actuator system and leak in the hydraulic control loop lines. Hydraulics actuator is to flex the nozzle for thrust vector control



As always ISRO is quite though in its development and testing process.

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