18 December 2014
This is the FM Gold
channel of AIR, In the Program News Analysis now we bring you a dialogue on successful
launch of GSLV Mark III. The participants are Ajay Lele, Research Fellow IDSA
and Dinesh C Sharma, Science writer.
The Indian Space Research Organization (ISRO)
today completed an important mission. The objective of this mission is twofold.
This launch the GSLV Mark III it was
an experimental flight of Geo-synchronous Satellite launch vehicle which was
underdevelopment, so that was the one part of the mission. The second part of
the mission was the testing of the crew
module, which would be used in the future man mission of ISRO which is
under planning for sometimes.
It
marks an another important landmark in the history of March of Space Agency
towards becoming a full-fledged space body which can do everything from right
from designing satellite to launching heavier satellite to operating them in
Scientific projects of larger dimension. So how
do we place today’s success in this journey of ISRO?
I
think it is an important movement in the journey of ISRO, particularly as far
as this launching system are concern, particularly the crew module aspect I
would say it is a baby step as far as India’s overall human mission is
concerned. But as far as the Launch vehicle is concerned, it is half part of a
mission, because essentially the entire GSLV
consist of 3 stages and the third stage which is extremely important that
is Cryogenic Engine which is under
the present stage of development. It will take another 2 years to launch that
mission but the most important aspects of this mission is that till date we
were depending on particular system for launch system mostly it is PSLV or variant of it. But right now
what we have done is both the first stage is solid stage and second stage which
is liquid stage has been freshly designed. So this is an important step form
the point of view that we have ventured in to new design. Because, we
understand that for launching satellite
more than 4 tonne in weight, we need to have a new design. So the first portion
of the design has been successfully tested today.
As
you said GSLV which was launched today is not full scale GSLV because the first
two stages
were there and it is the three stage rocket. And the third stage of course consists of Cryogenic
engine and in today’s launch they had a dummy engine. But I think lastly
what they wanted to test and qualify certain system which were used for the
first time, there were several new features in the first two stages itself. So
that which could have been tested on ground, they needed this flight, so they
call it an Experimental flight not
developmental flight. I suppose the developmental
flight, as the ISRO chairman today said is still 2 years away which will have an indigenous cryogenic engine.
You
look at the conventional design of the satellite design vehicle particularly
the listeners are were much aware of the PSLV Design very good 4 stages that is
solid, liquid again solid stage and liquid stage all these stages are mounded
on each other. As far as your Earlier
Mark 1 & Mark 2 GSLV also was concerned, you had a Solid stage, Liquid stage and Cryogenic stage. We were using for
certain launches, Russian Engine and for one launch we have successfully used
Indian Engine also for Cryogenic stage. But if you look at the first and second
stage, that is almost replica of PSLV design. Right now in this particular
thing what has happened is that, your first stage was part of the second also,
in that sense you had 2 separate
boosters otherwise we use to have huge solid state first stage. Instead of
that you got 2 separate boosters which essentially help to do differential
change in to the entire mission profile. And you had is liquid stage also,
interesting aspect is when the first stage is ignited at the same time the
second stage also ignited. So these are the few new features which they have
worked out. Because essentially here Mark
I & Mark II also were allowing you to carry the satellite in to the Geo Stationary orbit but weight it was
problem it was lesser than 3 tonnes. So if you want to launch the satellite of
higher payload satellite, essentially communication satellite that’s what the
requirement is. Recently we launched our satellite which has got 42 transponders, again we will be going
to France to launch another
communication satellite. So we want to reduce this dependence on other agencies
and from that perspective, I think this is above vital flight has been very
useful of ISRO and when they marry a cryogenic engine then I think India’s
space program would go leaps above.
Let’s
discuss something more about the Cryogenic engine itself. Because I think that
is very crucial for the future of India’s Space Program as we have discussed
that to launch larger category of heavier satellite on our own like
communication satellites or ultimately the man flight would go on GSLV. So in
that point of view development to indigenous Cryogenic engine is very crucial and which has been in the pipeline for quite sometimes.
If
we look at the early 1990’s .. suppose to be part with cryogenic engines, which
are custom made engine with Cryogenic technology also with in India. At that
time US raised the issue related to Missile Technology Control Regime and
argued if you part cryogenic technology to India, India would use it in its
missile program. But incidentally
India’s Missile program was a standalone separate program and India’s Space program is other standalone separate program. As far as
India’s missile program is concerned, India had already achieved what it
actually wanted to achieve. Were India’s effort drastically need was in the
development of cryogenic engine stage. Last 15 years also we are continuously
working on it; we had our own share of failures too. But If you really look at
the major two failures which happened were in 2010, when our both the satellite
launches failed one of them had Cryogenic engine which is Russian made, second
was indigenous cryogenic engine.
But
the first failure was not attributed to the cryogenic engine.
Exactly
and the Cryogenic was not Indian made also…
Now
the interesting aspect is that even though we were saying that India took so
much amount of time, only in the second attempt we succeeded with our cryogenic
technology. So, when in the beginning of this year we launched our satellite by
using indigenous cryogenic engine is succeeded with it. Now the issue is of the cryogenic engine what
we used for Mark II is not good enough for Mark III. So we need to certain
amount of more improvements in the cryogenic technology, and from that
perspective now we are working making cryogenic engine stronger. There are
other aspects of Cryogenic engine where you got a propellant which instead of
using liquid hydrogen, you end up using kerosene. We are working on that
technology also, when that technology when it gets developed will allow us to
launch satellites which are even more than 6 tonnes capability. So Cryogenic is
the thing were the work is still on and let’s hope with in next 2 years at
least cryogenic which is required for our GSLV Mark III gets successfully
developed.
I
think, the short term or you can say the medium term goal is to have perfect
this technology of Cryogenic, that we can start launching heavier satellite
form India like the GSAT which we launched from core institute of that which we
have capability of doing that from Indian soil itself. That should be the
medium goal.
Definitely,
If you really look at the way India’s PSLV
has become a successful work for last 27
launch we had done it successfully. So we want to have that sort of
capability available with us, with GSLV launcher also. When we get that sort of
capability available with us, it has about lot of implication as far as India’s
Space program is concern whether they are strategic
implication or commercial
implications or else what is the
core element of India’s Space program i.e. for the purpose of socio-economic
development. I think in all these three areas we will get a boost, and
definitely it will boost our moon
program and mars program too.
Chandrayan
II we also need requires a GSLV. So, it going to be the vehicle of the future; so we need to perfect the technology of
cryogenic and Mark III of GSLV. So in that direction today’s flight was an
important mile stone we are going in to the making of the final GSLV Mk III.
And coming to the payload, it was called (CARE)
as such Crew Module Atmospheric
Re-Entry. It is a sort of module
which ultimately takes humans to space. This is the thinking and this case for
the benefit of the listeners, you must clarify; this is not as if the module is
ready. And in fact these are the two
building modules for say to build crew module which will ultimately go in
to the space whenever India go in to a Man
mission. And in fact this was a design because Re-entry is an important
aspect whenever an object goes in to space and wants to come back, coming back
part is more important. In fact that’s where the crucial technologies are
required at the Re-entry point.
Because,
at that point the temperature; sore too high.
I
think at this point of time, we have to give example of the sad case of the
demise of Indian origin astronaut Kalpana Chawla. In her space craft when it
was re-entering in to the Earth’s Atmosphere, because of the thermal shield of the craft had not worked
properly, that’s why it got disintegrated. Issue over here is, as the space
craft is entering in to the Earth Atmosphere, Huge temperature different would
be experienced by the space craft. The temperature reaches to the tune
1000-2000 degree Celsius. Until and unless you have the technology capable of
withstanding these sorts of temperature, you can’t really send human to the space. But if I slightly
go back, in the year 2007, India had
done the first experiment on SRV ie.
Space Recovery Vehicle. And that point of time, the payload which we had
sent was is of 555 kgs expressively of small payload. This time we had sent
payload of 3.6 tonnes that means 3600 kgs. And that payload has definitely
withstood the test of the temperature and it has been pushed in to the Bay of
Bengal at the designated location. Now I think what is important is that even
though we are celebrating the success, after this particular crew module will be taken up by the coast guard, again
certain amount of analysis of what
is actually happened to the surface of the crew module and that also will give
more amount of important data, that how it has withstood and what sort of impact that soring temperature
had on this crew module.
Normally
these crew modules like Chinese, Russian and American were used and we learnt
lesson from those technology and we have improved up on that. These crew
modules have something called Heat
Shield, So that the high temperatures when they are reaching the heat
doesn’t get transfer to the module and the human inside the space craft. That
is the whole purpose of the Heat shield. And those of some kind of special
material which have been used here what they called a blazing, in that sense
these material when heated vaporize and the heat doesn’t get transfer in to the
module itself.
Therefore sometimes you see that these object looks like a fire
ball entering in to space. That is a key technology, which is ISRO has been
able to develop, these material are again of Strategic, I would say, not
available of the self. We need to have the capability of developing special
materials for the modules like this.
We
have developed some materials, because the material stands as the key over
here. And I think since 2007 onwards, we have been doing consistent
development, I am sure that ISRO must have learnt something from there 2007 SRV
experimentation also. And that knowledge must have also allowed them to
improvise this technology for such a bigger mission. At the aspect of this
landing is the parachute which has been developed. Now what happens is that,
now we have to change in to the speed, because what happened when the crew
module was released at the height of 126 Km
and the free fall started, after it enters in to the 80 km of further, it
encounter huge of amount of temperature different, and subsequently again the
free fall was taking place, but you need to control the movement of this
particular craft or crew module.
Reduce
the speed, reduce the velocity. For this purpose we have special parachutes we
have made. Initially say 13 minutes, because after the launch took place at 5th
minute, the capsule was release and it started coming back. And after say 13th
minute, the first smaller parachute was opened up, it has allowed it to decelerate the speed to certain level.
And as it comes closer to the Earth, again the bigger parachute, remind you the
diameter of the parachute was 31m. Huge parachute because it can withstand the
weight of the module which is 3.6 tonnes.
The
speed is reduced from several Km/sec to
few metre/sec.
That
is again very interesting aspect. If you really look in to how the ISRO had
prepared for this. Few days back or few years back they have tested this crew
module but putting the module into a helicopter, it was taken to the height of
3.5 km and from there it was dropped.
I
see these are the crucial technological building blocks towards the ultimate
goal of, you know developing man mission. And I think the developments are
going parallel, in one hand we are putting all our efforts in to developing a
Cryogenic rocket which ultimately when the mission is ready can take the Human
module. We need to develop a lot of technology, to make this module hospitable for the human to live there and several
other parameters. The module itself like
a satellite, it has propulsion system, guidance system, navigation system…
And hopefully the Government would prove as the ISRO scientist and Community
expects that Man mission would be approved and all this Inputs would go into
it.
You are listening to a
dialogue on Successuful launch of GSLV Mk3. The participants are Ajay Lele,
Research Fellow IDSA and Dinesh C Sharma, Science writer. This came to you in
the program News Analysis produced & presented by News services division on
All India Radio.
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GIST: Successuful launch of GSLV
Mk3
Twofold
objective – Geo-synchronous Satellite Launch(GSLV) & Testing of Crew Module
; GSLV – 3stages – III stage is extremely important that is of Cryogenic Engine
– as till date we depend up on PSLV – successful work with 27 launch; Cryogenic
what tested today is Experimental flight – Developmental flight yet be ready in
2 years; GSLV Mk I & II – has solid, liquid & cryogenic stage - which
is not capable of launching payload more than 3 tonnes; Recently: to launch
communication satellite with 42 transponders (3.4 tonnes) – we went to Franch;
Cryogenic engine is crucial – to reduce this dependence; 1990 – US – MTCR issue
– hinder the Cryogenic Technology transfer – suspecting it to be used in
Missile Technology; but incidentally both Space Program & Missile program
of India is standalone Separate Programs; GSLV Mk3 – Strategic implication,
Commercial implication & core element of such program is socio-economic
development; our moon mission Chandrayan II also required GSLV;
Crew
Module – CARE (Crew Module Atmospheric Re-Entry) the second part of the test;
sad demise of Kalpana chawla – thermal shield not worked properly –
temperature reached 1000-2000 c in the
re-entry; SRV tested in 2007 by ISRO – Space Recovery Vehicle – which is just
555 kg very minimal what we required is – capability of carrying 4 tonnes of
Payload; Heat Shield & Parachute system of GSLV Mk3 – Heat shield of a
Blazing material – when heated vaporize & prevent the heat transfer into
the module; Parachute system for safety landing – small parachute – decelerate
the speed from several Km/sec to few metre/sec; Further it need to be made more
hospitable; The module itself mini-Satellite with Propulsion sys, Guidance Sys,
Navigation sys; Both this Cryogenic & CARE is the building blocks for
Bigger goal of MAN MISSION which await government approval;
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