Sci & Tech

ISRO aims to catch up with satellite demand with 18 launches per year

“Our aim is to meet the immediate requirement with a target of 18 launches per year ; The Chandrayaan-2 mission will also be launched this year.” said ISRO Chairman Dr.Sivan.

Just days after taking on new responsibilities, Dr. Sivan shares his plans for ISRO’s stepped up launch schedule and steps towards manned space flight.

You have just taken charge as Secretary, Department of Space, and Chairman, ISRO and the Space Commission. In the country’s space programme which area do you think needs immediate attention?
We now have 43 satellites in space — for communication, earth observation and navigation. To meet the present national requirement, we need an equal number of satellites in addition. The frequency of launches must definitely increase. With the present launch capability, it will take us four years to make the required satellites and launch them. By then we would need to replace a few [older] satellites. It is like trying to catch up with a moving bus! This gap can be met only by increasing the launch frequency. Our aim is to meet the immediate requirement and for that, we have set 18 launches per year as the target.

For over a decade now, ISRO has been facing a serious shortage of satellite transponders because of an unforeseen demand from various users and leasing some capacity on foreign satellites. How will you tackle the gap?
Yes, we are really short of around 100 transponders. But we are going to manage that with the new satellites that we will launch. We hope to bridge the gap very soon. One major satellite that we plan to launch in a couple of months is GSAT-11. It is around six tonnes [6,000 kg]. Once it is launched and starts working, most of our problems should be solved. It is getting ready and launch date is not fixed. We will launch it from Kourou [in French Guiana, South America].

Do you see a need to change or re-focus activities related to development of launch vehicles, satellites and infrastructure?
There is really no need to change anything. In ISRO we define our priorities and requirements very clearly and well ahead. We have a clear plan up to 2025 for launch vehicles and spacecraft. Beyond that, too, there is an outline as to which way we should go. We have a three-year action plan.

Which missions are coming up this year?
As a part of the three-year short-term action plan, immediate missions that we plan to do this year are the GSLV-F08 that will launch the GSAT-6A communication satellite [around February]. Then we will have a PSLV mission with navigation satellite IRNSS-1I. Then comes the second developmental flight D2 of GSLV-MkIII. It will launch the high throughput satellite GSAT-29. Later, GSAT-11, which will be our heaviest satellite as of now, will be launched from Kourou. The Chandrayaan-2 mission will be launched this year on another GSLV.

At what stage are some of ISRO’s ambitious projects — the semi-cryogenic launch vehicle and the human space flight ?
For the semi-cryogenic launch vehicle, the engine development is going on. Some critical [sub-systems] are getting fabricated or tested. Our target is to test fly it sometime in 2019.

The human space flight is really not in our approved programmes for now. Before it is taken up, a human mission requires many technologies. We should develop them and be ready to execute it in a shorter period. For example, the crew module shaping, certain thermal systems and the CARE (Crew Module Atmospheric Re-entry Experiment) that was tested in a partial flight of the GSLV-MkIII in 2014.

In the case of any disaster, there should be an emergency plan to rescue the crew from the capsule. One such experiment called ‘pad abort’ will be taken up this year. Studies related to life support systems, space suits, cabin pressure, oxygen levels, crew hygiene etc. should be completed.

Last year, a plan was initiated to entrust the entire production of PSLV launchers to industry. A similar plan is under way to produce satellites. What is their status and how will this plan help?
The process is on to give the major chunk of PSLV production to industry. Internal committees are looking at how to make work packages [i.e. distribute tasks.] The selection process is on. The first PSLV from industry should roll out in 2020. If this happens, it will take care of half our job. More people in ISRO will be available for doing R&D.

Of the target of 18 launches per year, we would like to do 12 to 13 PSLVs, of which a major chunk would be through industry; three GSLVs and two GSLV-Mark IIIs.

Except for defining the modalities, which will take time, I would say that it should not be an issue for us. Major industries such as HAL (Hindustan Aeronautics Ltd,) L&T, Godrej and MTAR have been already contributing to our programme in big ways. A similar thing is happening in the satellite area also, although industry has already built one satellite under ISRO’s guidance.

Beyond these, we are developing a new launch vehicle to put small satellites to space.

We want to hand over its technology and production to industry right from the beginning after doing one or two technology demonstration flights. We will do this through [ISRO’s business entity] Antrix Corporation.

When will public services based on the Indian regional navigation constellation NaVIC begin?
This is an area of priority for me — to make micro and miniaturised NaVIC receivers and see that they get into our mobile phones. I am very clear about it — that any mobile without NaVIC receivers will not be allowed to be sold. How we can cajole industry to do this will take time.

Which are some of the new areas of focus for ISRO?
We should aim for reducing the total mission cost. The satellite cost should be less, so also the cost of the launch vehicle. This will be possible when both are smaller than now. A promising technology in this area is the EPS or electric propulsion system on satellites. By bringing this in, the satellite’s size will automatically come down. A four-tonne spacecraft, for example, can do the work of a six-tonne satellite [as less fuel will be carried to space.] The launcher can also be smaller and automatically the mission cost can come down.

But we don’t get anything without a price. In EPS we lose something: we have to wait for 6-12 months for the spacecraft to slowly reach its destination because the thrust level is low. The vehicle injects the satellite in a GTO [a temporary geostationary transfer orbit.] For the satellite to move from there to the final orbit, the increase in the orbit size will be very, very slow. Because the thrust level will be a maximum of about 300 milli Newtons. The satellite’s service life is cut short.

See the difference with chemical propulsion that we now use —it gives us a 440-Newton thrust. The satellite can move from there to the final home within a few days.

But there are ways to beat this. The Liquid Propulsion Systems Centre is trying to improve the thrust or muscle power that we get from the EPS. We are also developing the technologies for a future reusable launch vehicle.

We should also think of innovative applications. We are trying to synergise the inputs of all 43 satellites.

We are pushing hard in the applications area. Recently we validated a new mobile app to help fishermen. It tells them where they can find large fish shoals in the sea. It has become very popular and we have to now ensure that our industry produces them in good numbers.

The draft Space law will be taken up further. We hope to have it this year.

In last year’s Budget, the Department of Space was allocated ₹9,903 crore. What kind of resources would be needed for future missions?
[Smiles] We never had any problem with budgetary outlays! The problem is more in executing [using] it. But definitely [we can do with] more. More satellites are required to be put in orbit and they need more launch vehicles. We also need more facilities to make them. So it means that much more money is needed on the launch vehicle side, spacecraft side and on the infrastructure side. A bigger vehicle needs more hardware, which comes to nearly 85% of the cost. We also have to bring the production of launch vehicles to industry — and it needs extra money.

Of course, all this is projected to the government.

Would you look at a third launch pad at your Sriharikota launch centre to increase the pace of launches?
No, we are not talking of a third launch pad now. Instead we are augmenting the FLP [or LP1, the first launch pad, built in the 1990s] with a separate structure. Once you integrate a launch vehicle in one facility or launch pad, that facility will get locked for 45-60 days. The system is destroyed after every launch and it has to be refurbished each time. In this situation, even if we do continuous launches, we can do only six a year. But with multiple systems, we can be always ready to put launch vehicles together.

The capacity of the propellant plant should also be increased.

By: The Hindu

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