New Delhi:
The countdown for one of the biggest launches by ISRO has begun. The lift-off of ISRO GSLV will take place from the second launchpad at its spaceport in Sriharikota. The INSAT-3DR satellite will be carried by ISRO GSLV-F05 rocket, which will take it to a geostationary transfer orbit around Earth. So, what makes the launch of advanced weather satellite INSAT-3DR important? Here are some reasons:
ISRO’s fourth launch using an indigenous cryogenic engine
In April 2001, the first test flight of the GSLV with a cryogenic upper took place, however, it failed. After that, the rocket made eight flights over the past 14 years. Out of 14, five had a Russian cryogenic engine, while three others were powered by the indigenously developed ones. Three turned out to be successful, while four failed and one achieved partial success. The first successful test flight with a Russian engine took place in May 2003. First successful test flight using an indigenous engine happened in January 2014.
An indigenous cryogenic engine will be used on an operational flight for the first time
ISRO will not test any components, flight parameters or flight routes since it will be an operational flight. The launch’s sole mission will be to deliver the payload. In 1986, ISRO made plans to develop a cryogenic engine to be used in rockets. ISRO received offers to develop engines from three different entities – US, Soviet Union and France. The space agency accepted an offer from a company named Glavkosmos in the erstwhile Soviet Union as the other two were not affordable.
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However, sanctions were imposed on India and Russia by the US government after the Russian company and ISRO refused to call their deal off upon American insistence. This made the Boris Yeltsin government in Russia to pressure Glavkosmos to call off its partnership immediately. ISRO was thus left with finding its own way. However, it had received seven cryogenic engines and one mock-up for testing at some additional cost from the company. Later came the indigenous engines that were built at the Liquid Propulsion Systems Centre in Thiruvananthapuram. The cryogenic engine allows the GSLV to lift upwards of 1,500 kg to the geostationary transfer orbit, while the PSLV rocket cannot carry anything heavier than 1,400 kg.
The INSAT-3DR satellite continues the mission of INSAT-3D satellite
The mission of the INSAT-3D satellite, which was launched in 2013, continues with the INSAT-3DR satellite. Both belong to ISRO-operated larger class of meteorological satellites, including the KALPANA-1 and the INSAT-3A. KALPANA-1, INSAT-3A and INSAT-3D have already been placed in the geostationary orbit.
The F05 mission, scheduled for Thursday, will witness the GSLV-MkII launch the INSAT-3DR into the geostationary transfer orbit. It will use its built-in propulsion systems to manoeuvre into its eventual geosynchronous orbit. The mass launch of the satellite is 2,211 kg, while 1,255 kg of this is in propellants.
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The INSAT-3D satellite possessed an atmospheric sounding system and was an improved version of its two predecessors. The atmospheric sounding system helped it map vertical changes of humidity, temperature and ozone content in Earth’s atmosphere. The INSAT-3DR will be able to make the same measurements, at the same time, it will provide better image night-time clouds, and better measure sea surface temperature. Like 3D, the 3DR will also have a search-and-rescue transponder, used to pinpoint the location of distressed vessels at sea.
The 3D will be operational until 2021, while the 3DR around 2024. INSAT-3DS, a second successor, is likely to get operational from 2022 to 2029. The 3B and 3C are not operational.
GSLV-Mk-III success is important for ISRO
The three types of GSLV– Mk-I, Mk-II and Mk-III – have a solid-fuel first stage and a liquid-fuel second stage. For the third stage, the Mk-I uses Russian make cryogenic engines. Four liquid-fuel strap-on boosters are used by the Mk-II in addition to the first stage, while for the third it uses the CE-7.5 indigenous cryogenic engine.
For the first stage, two solid-fuel boosters will be used by the Mk-III, while for the third it will have the CE-20 indigenous cryogenic engine. The first developmental flight of the Mk-III is likely to take place in December 2016. It will also carry the 3.2-ton GSAT 19 satellite during the launch.
A flight that took place in December 2014 had only two functional stages as the CE-20 engine used by it was under development. The Mk-III will make ISRO self-sufficient in terms of launch capabilities.
May compete against SpaceX’s Falcon 9 rocket
Once the Mk-III is ready, its payload capacity of around 4,000 kg to the geostationary transfer orbit will put it in direct competition against SpaceX’s Falcon 9 rocket. A Falcon 9 launch costs around $62 million.
