The ISRO has had it share of failed programmes. But what is important to note is that the organisation is a quick learner and has always tried to overcome its inadequacies. Now the ISRO is planning to launch its latest communication satellite, INSAT-4CR, from Sriharikota spaceport on September 2, and it is basically to make up for the launch failure of INSAT-4C. That satellite had failed to reach orbit due to a launch vehicle malfunction. After the Geo-Synchronous Satellite Launch Vehicle (GSLV) followed, more or less, its predefined trajectory for about 12 km, it started veering off course, because the first stage failed to separate. Its four strap-on motors failed to work during the initial stage of the launch, causing an approximate loss of Rs 250 crore.

The proposed INSAT-4CR (R stands for replacement) mission is an identical mission with a lifespan of 10 years. It carries 12 high-power Ku-band transponders designed to provide direct-to-home (DTH) television services, facilitate video picture transmission and digital satellite news gathering. This entire INSAT-4 series is a series of seven satellites, with 4A and 4B being already operational.

The INSAT-4CR will be launched by a three-stage GSLV into geosynchronous transfer orbit (GTO). This vehicle is capable of putting around 2,500-kg class satellites into the orbit. The ISRO has designed the first stage of this vehicle based on its PSLV design — a large solid rocket augmented by four liquid fuelled strap-on boosters. The second stage is the liquid fuel stage, again based on PSLV design, powered by a Vikas engine. The third stage is a cryogenic stage. Earlier this stage had been powered by the Russian KVD-1M engine but now an Indian built cryogenic stage engine has replaced it.

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