The Indian Space Research Organisation (Isro) has had a challenging time in recent years and chairman K Radhakrishnan talks to Praveen Bose about some of this. Edited excerpts:
You have been increasing the frequency of launches. What are you doing to increase the launch capacity?
We are planning a third launch pad at SHAR (the Satish Dhawan Space Centre, at Sriharikota island, off the Andhra coast). A launch blocks the pad for nearly 60 days. To increase the frequency, we need more launch pads. We are seeing what the requirements are.
It is not just for the GSLV Mark-III (the new launch vehicle being planned) alone that we are in need of a launch pad. We are also planning a unified configuration launch vehicle. It is a semi-cryogenic and cryogenic stage-I. Unified configuration has the growth potential. The third launch pad will take care of this requirement. It may also be used in possible human flights. All the launch pads should be such that we should be able to use the common facilities. We are planning such an infrastructure at Sriharikota. Meanwhile, we are also considering a second launch site. We are now talking of a feasibility study of this.
What kind of technologies are you developing and how are you planning to expand the infrastructure?
We have developed a flex nozzle that’s used even in the PSLV, due to which the vehicle can be controlled remotely. But, it’s a small one. In GSLV Mark-III, the requirement is enormous. The development of the vehicle is on and infrastructure at the Vikram Sarabhai Space Centre and at SHAR are being enhanced for this.
Isro can today launch a four tonne-class geostationary satellite. If it is in the low-earth orbit, then we can go up to 10 tonnes. In the GSLV, 50 per cent of the velocity will be provided by the cryogenic stage. All studies, though, are to be done. Solid motors and boosters are not flexible. However, they’re now steerable because of the flexible technology. We have the actuator requirement and the ability to have materials that can withstand very high temperatures.
What is the transponder shortage for India? How do you intend to make up?
What is the progress on the attempt to augment transponder capacity?
We have 86.5 transponders on lease. We facilitate the process. In the next few months, we will get some more on lease. Earlier, we had 151 transponders. With the GSAT-8 and GSAT-12, we will have 36 more transponders with the launch of GSAT-10 in the second quarter of 2012. It will be launched on board Ariane-5 (the rockets made by the European Space Agency, used to launch payloads into low Earth orbit).
We are getting ready to have a contract with Ariane. The GSAT-10 will have three types of transponders, in the Ku, C and extended-C bands. We will also repeat the GSAT-8 and GSAT-10. The satellites will be 3.3-3.4 tonne class of satellites. At the end of the 11th five-year Plan (March 2012), we will have 251 transponders; the target was 500. Several satellites failed. Insat-4B had a partial failure. Then, the capacity fell to 152. Then, we added Insat-4CR.
You are lately encouraging students and universities to build small satellites. How does it help Isro?
The student satellites are Isro’s programme for the academic community. Here, students and faculty learn about all systems — engineering and other aspects of a satellite. They get a feel of the whole process for building one. Plus, we get data, and we analyse it. It helps Isro. We are developing people who are interested. We are able to get projects like Anusat, which is a small satellite with good instruments. We want to promote such endeavours. We have a template for this. Some IITs want to develop basic instruments for satellites.