Indian Space Programme Discussion - Sept 2016

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Re: Indian Space Programme Discussion - Sept 2016

Postby Picklu » 16 Apr 2018 00:54

SriKumar wrote:If this thing does not get sorted out in an year or so, perhaps one could consider launching a 'relay communication' satellite with a GSLV launch (in addition to the scheduled payload). This 'relay comm' satellite should be brought to the same orbit and in proximity to the disabled satellite to establish communication. (alternatively, a pre-scheduled payload going via the same intermediate orbit could be programmed to do some relay communication functions in the orbit of the disabled satellite before it goes on to its final orbit).

At a minimum, it can send pictures of the orientation of the GSAT6 satellite and determine how the satellite is spinning/antenna is oriented w.r.t time etc. Once the spin rate/antenna attitude is known, the relay satellite could be positioned to transmit a signal. All of the above applies if it is 'only' a matter of getting a signal into the disabled satellite, which per public domain information is the problem. (If there are other issues, then I dont know). It is not clear what has caused the (i) power loss, and (ii) communication loss (loss of earth lock obviously). The solar panel is deployed, so it does have power from an active power source. Some circuit issue perhaps.



The CT theorist in me speculates that we have just launched the business case for our own space docking/capturing experiment

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Re: Indian Space Programme Discussion - Sept 2016

Postby kit » 16 Apr 2018 03:55

It would be a great experiment if we could turn this problem into an opportunity .. send off an "engineer satellite" to fix the problem :mrgreen:

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Re: Indian Space Programme Discussion - Sept 2016

Postby prasannasimha » 18 Apr 2018 19:32

Apr 15, 2018 : The fourth and the final orbit raising operation of IRNSS-1I is successfully carried out at 21:05 hr IST on April 15, 2018. The achieved perigee height is 35,462.9 km and apogee height is 35,737.8 km

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Re: Indian Space Programme Discussion - Sept 2016

Postby chetak » 19 Apr 2018 18:22

Picklu wrote:
SriKumar wrote:If this thing does not get sorted out in an year or so, perhaps one could consider launching a 'relay communication' satellite with a GSLV launch (in addition to the scheduled payload). This 'relay comm' satellite should be brought to the same orbit and in proximity to the disabled satellite to establish communication. (alternatively, a pre-scheduled payload going via the same intermediate orbit could be programmed to do some relay communication functions in the orbit of the disabled satellite before it goes on to its final orbit).

At a minimum, it can send pictures of the orientation of the GSAT6 satellite and determine how the satellite is spinning/antenna is oriented w.r.t time etc. Once the spin rate/antenna attitude is known, the relay satellite could be positioned to transmit a signal. All of the above applies if it is 'only' a matter of getting a signal into the disabled satellite, which per public domain information is the problem. (If there are other issues, then I dont know). It is not clear what has caused the (i) power loss, and (ii) communication loss (loss of earth lock obviously). The solar panel is deployed, so it does have power from an active power source. Some circuit issue perhaps.



The CT theorist in me speculates that we have just launched the business case for our own space docking/capturing experiment


I gathered that thermal management is also an issue that has started to bother ISRO. If the temps rise/drop below the specified values it could make the difference between recovery and loss.

They are unable to get a read on this aspect, in addition to all the other issues.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Indranil » 19 Apr 2018 18:44

My theory is that once they can get any kind of signal going, they will first try to slow the rotation using onboard motors.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Vips » 23 Apr 2018 07:56

Isro to launch slew of military satellites soon.

Amid preparations for its high-profile Rs 800 crore Chandrayaan-2 mission scheduled for an October launch, Indian Space Research Organisation (Isro) is also gearing up to launch a slew of important satellites in the coming months.

Some of these satellites are significant for strategic reasons as they will help the military keep an eye on our hostile neighbours and safeguard our land and sea borders.

Isro will launch a dedicated satellite, Gsat-7A, for the Indian Air Force (IAF) in September and an advanced remote sensing satellite, Risat-2A, for surveillance purpose by the end of the year.

Gsat-7A, which will be lifted by a GSLV Mk II rocket, will enable the IAF to interlink different ground radar stations, airbases and AWACS aircraft. It will also boost the IAF’s network-centric warfare capabilities and enhance its global operations.

The satellite will be similar to Gsat-7 or Rukmini, which was launched on September 29, 2013, exclusively for the Navy. Rukmini has helped the Navy monitor the Indian Ocean Region (IOR) as the satellite has a nearly 2,000 nautical mile ‘footprint’ and provides real-time inputs to Indian warships, submarines and maritime aircraft and also boosts the force’s networking capabilities on the high seas. Rukmini, considered the Navy’s ‘eye in the sky’, is also being used to keep tabs on Chinese warships in the Indian Ocean.

Risat-2A, which will be launched by the end of this year by a PSLV rocket, is an advanced remote sensing satellite that will boost the country’s surveillance capabilities. The satellite, which will carry a sophisticated synthetic aperture radar that operates at 5.35 GHz in C band, will help in earth observation irrespective of the light and weather conditions of the area.

Risat-2A, which can be used for civilian purpose, will primarily be used for land mapping but will also be significant for analysis of the ocean surface. Risat-2A will be the third in the series of Risat satellites.

After the 26/11 terror attacks in Mumbai in 2008, Risat-2 satellite took priority over Risat-1 and was launched in April 2009 as the former carried an Israelbuilt X-band radar, which boosted surveillance capabilities of the security forces.

Cartosat-2 series satellite, launched on January 12, is also a remote sensing satellite and significant for the military too as its panchromatic camera can produce images less than 1 metre in resolution. In fact, it is said that the Army used images from the earlier Cartosat satellite to plan the surgical strikes on Pakistan terror launchpads in September 2016.

Besides the military satellites, Isro will also launch its “heaviest satellite ever” Gsat-11 weighing 5.7 tonnes from French Guiana by June. The heavy-duty communication satellite is so massive that each solar panel is over four metres long, equivalent to the size of a room. The high-throughput satellite, which will carry 40 transponders in the Ku-band and Kaband frequencies, is capable of “providing high bandwidth connectivity” with up to 14 gigabit per second (gbps) data transfer speed.

Gsat-29, which too is a communication satellite, will be the launched by the second developmental flight of Isro’s heaviest rocket GSLV Mk III in June. It will carry multi-beam and optical communication payloads.

Isro chairman Dr K Sivan told TOI, “Together, all these heavy-duty Gsats will provide high-bandwidth connectivity of up to 100 gigabit per second. They will provide high-speed internet connectivity in rural areas as well and help bridge the digital divide.”

With almost one launch every month, 2018 will be a busy year for Isro.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Hiten » 24 Apr 2018 15:55

an exploded view of the Bhaskara 1 satellite - India's 1st Earth Observation satellite & its second ever satellite, launched in 1979

Image

unconfirmed report says GSAT-11 launch postponed. Satellite returns back to India. Entire mission scrubbed

https://www.spaceintelreport.com/last-m ... cancelled/

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Re: Indian Space Programme Discussion - Sept 2016

Postby JTull » 24 Apr 2018 18:59

Hope ISRO clarifies soon on this GSAT-11 news.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Vips » 25 Apr 2018 00:02

GSAT-11 launch postponed as Isro wants additional checks

Just weeks after the Indian Space Research Organisation (Isro) lose contact with GSAT-6A, the launch of another powerful communication satellite with military applications—GSAT-11—has been postponed.

The 5,725-kg satellite, which was scheduled for a May 25 by Arianespace from Kourou, French Guiana, was expected to usher in an age of high-speed internet connectivity that could provide speeds of up to 14 Gbps (gigabit per second).

Sources said that the Isro will now conduct a few more additional tests on the satellite as a precaution and to rectify glitches. The satellite, which had already reached the launch site will now have to be brought back.

The satellite, whose revised launch schedule could not be confirmed immediately, will carry 40 transponders in the Ku-band and Ka-band frequencies, “It provides 32 user beams in Ku-band and eight gateway beams in Ka-band,” Isro had said.

While no official confirmation was available from Isro, Arianespace, while confirming the postponement, said in a statement: “Due to additional technical checks with the Isro GSAT-11 satellite, to be conducted from the Isro Satellite Centre located at Bengaluru, the Ariane 5 launch initially planned for May 25, 2018, has been postponed.” Good to re-check now rather than sending it with a worry.

While Ariane said that none of its other scheduled launched is impacted, sources said that the GSAT-11 developed a few technical problems after reaching the launch site. The satellite had reached French Guiana on March 30.

The GSAT-11 was one of Isro’s high profile launches this year, with other satellites including GSAT-19 planned for later.

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Re: Indian Space Programme Discussion - Sept 2016

Postby ramana » 25 Apr 2018 00:34

Does GSAT 11 have common components as the GSAT-6A? Especially the orbit raising motor and its controls.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Haridas » 25 Apr 2018 04:40

^^^ Orbit raising LAM has been standardized for all satellites built in the last 30 years.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Singha » 26 Apr 2018 08:03

engaluru: ISRO has rescheduled the high-profile launch of its advanced communication satellite GSAT-11, the heaviest made in India, from Kourou, French Guiana, for additional technical checks, and recalled the spacecraft.

"The Indian Space Research Organisation's move to put off the May 25 launch comes weeks after the country's communication satellite with military applications GSAT-6A went missing after a perfect launch,” ISRO Chairman K Sivan said, adding that they wanted to carry out some tests and the satellite was in the process of being shipped back.


"We wanted to do some tests. That is all," he told PTI. Replying to a question, he said: "Right now, it is planned to bring the satellite back to India to carry out some tests and then we will be taking it back," he said, adding no time frame could be set for the process

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Re: Indian Space Programme Discussion - Sept 2016

Postby Singha » 26 Apr 2018 08:21

Better safe than sorry with such a high value and 1st time payload. Ariane is always available

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Re: Indian Space Programme Discussion - Sept 2016

Postby ramana » 27 Apr 2018 20:26

prasannanarsimha, Is there a description by ISRO of the final orbit raising maneuvers for GSAT series?

Why is the GSAT 6A spinning? Is it spin stabilized?

Thanks, ramana

The satellite is stabilized as it has a large unfurlabble 6 meter antenna. It is not supposed to spin but stabilized by attitude control thrusters etc

Possible cause is due to a power outage due to some connector issue. The issue occurred just before the final orbital raising burn.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Hiten » 27 Apr 2018 22:26

Docking experiment underway at ISAC

Image

via https://www.spansen.com/2018/04/indian- ... iment.html

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Re: Indian Space Programme Discussion - Sept 2016

Postby prasannasimha » 29 Apr 2018 22:57

https://timesofindia.indiatimes.com/india/isro-to-check-gsat-11-power-system-redundancy-logic/articleshow/63956798.cms

Isro to check GSAT-11 power system redundancy, logic
Chethan Kumar | TNN | Apr 29, 2018, 04:27 IST


HIGHLIGHTS
The satellite was to be launched on May 25 from Kourou, French Guiana, by an Arianespace rocket
It will now be subjected to repeated thermal vacuum tests, among other things
Most tests to be conducted at the Isro Satellite Centre are related to the power system
Isro chairman K Sivan. (TOI file photo)Isro chairman K Sivan. (TOI file photo)
BENGALURU: The Indian Space Research Organisation (Isro), which last week decided to call back the GSAT-11 satellite, India's most powerful communication satellite, is addressing "potential glitches" linked to the satellite's power system based on lessons learned from GSAT-6A, which lost contact with the ground station.


Isro chairman K Sivan said: "A committee of experts comprising former Isro chairmen advised us to bring back the satellite for more tests." Members of the committee said they wanted to resolve a number of "potential failures".
The satellite, which was to be launched on May 25 from Kourou, French Guiana, by an Arianespace rocket, will be subjected to repeated thermal vacuum tests, among other things. Most tests to be conducted at the Isro Satellite Centre here are related to the power system.

Former Isro chairman and committee head K Kasturirangan said: "There are some concerns from the previous mission that are not fully addressed. We'll run more tests on the ground and in the space simulation chamber. The tests will be related to certain redundancies in the power system."
The 5,725-kg satellite will usher in high-speed internet connectivity, especially in rural India. The satellite is expected to reach India in the first week of May. Isro is yet to announce the rescheduled launch date.

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Re: Indian Space Programme Discussion - Sept 2016

Postby jaysimha » 30 Apr 2018 14:43


ramana
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Re: Indian Space Programme Discussion - Sept 2016

Postby ramana » 01 May 2018 01:10

Haridas, 8)!!!

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Re: Indian Space Programme Discussion - Sept 2016

Postby ramana » 01 May 2018 01:47

prasannasimha wrote:https://timesofindia.indiatimes.com/india/isro-to-check-gsat-11-power-system-redundancy-logic/articleshow/63956798.cms

Isro to check GSAT-11 power system redundancy, logic
Chethan Kumar | TNN | Apr 29, 2018, 04:27 IST


HIGHLIGHTS
The satellite was to be launched on May 25 from Kourou, French Guiana, by an Arianespace rocket
It will now be subjected to repeated thermal vacuum tests, among other things
Most tests to be conducted at the Isro Satellite Centre are related to the power system
Isro chairman K Sivan. (TOI file photo)Isro chairman K Sivan. (TOI file photo)
BENGALURU: The Indian Space Research Organisation (Isro), which last week decided to call back the GSAT-11 satellite, India's most powerful communication satellite, is addressing "potential glitches" linked to the satellite's power system based on lessons learned from GSAT-6A, which lost contact with the ground station.


Isro chairman K Sivan said: "A committee of experts comprising former Isro chairmen advised us to bring back the satellite for more tests." Members of the committee said they wanted to resolve a number of "potential failures".
The satellite, which was to be launched on May 25 from Kourou, French Guiana, by an Arianespace rocket, will be subjected to repeated thermal vacuum tests, among other things. Most tests to be conducted at the Isro Satellite Centre here are related to the power system.

Former Isro chairman and committee head K Kasturirangan said: "There are some concerns from the previous mission that are not fully addressed. We'll run more tests on the ground and in the space simulation chamber. The tests will be related to certain redundancies in the power system."


The 5,725-kg satellite will usher in high-speed internet connectivity, especially in rural India. The satellite is expected to reach India in the first week of May. Isro is yet to announce the rescheduled launch date.


So the GSAT -6A failure was big enough to have a Committee headed by former ISRO chairman and have another as its member.

I had told a member on Friday, that GSAT-11 being brought back is significant as they know the failure mode and want to screen for it.

looks like its right track.

TVC testing is to ensure no arcing/shorting.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Haridas » 01 May 2018 10:51

power system redundancy, logic
On the dot. The vacuum testing to adequately test and nail the power system centric failure.

Many years ago met Kasturirangan at his office when he was heading NIAS Bangalore.

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Re: Indian Space Programme Discussion - Sept 2016

Postby hnair » 02 May 2018 12:02

FWIW, seems the GSAT11 has exact same sub systems, that are suspect in 6A's issues. Since -11 was shipped to Kourou before the failure of 6A opened the issues up, they had to get it back at great cost, fix and test. The scrubbed launch will take months to re-organize, but for a huge capital asset, the cost was deemed to be within limits.

Since it is a power issue with no apparent backup in sight, even a regain of comms *might* not help 6A :(

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Re: Indian Space Programme Discussion - Sept 2016

Postby Singha » 02 May 2018 12:46

Its good . They are putting best people on it and serious about failure root causing

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Re: Indian Space Programme Discussion - Sept 2016

Postby prasannasimha » 02 May 2018 23:27

Think of connections and that will be the cause.
Do connectors and convertors cause arcing if faulty?
Solar panels generate DC current isn't it

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Re: Indian Space Programme Discussion - Sept 2016

Postby Prithwiraj » 03 May 2018 00:24

hnair wrote:FWIW, seems the GSAT11 has exact same sub systems, that are suspect in 6A's issues. Since -11 was shipped to Kourou before the failure of 6A opened the issues up, they had to get it back at great cost, fix and test. The scrubbed launch will take months to re-organize, but for a huge capital asset, the cost was deemed to be within limits.

Since it is a power issue with no apparent backup in sight, even a regain of comms *might* not help 6A :(


More than the actual monetary cost I feel the perception cost of preventing back to back failures is factor here and it is definitely low

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Re: Indian Space Programme Discussion - Sept 2016

Postby Haridas » 03 May 2018 11:48

prasannasimha wrote:Think of connections and that will be the cause.
Do connectors and convertors cause arcing if faulty?
Solar panels generate DC current isn't it

Yes, when faulty.
Most new converter designs employ progressivly higher freq. Higher the frequency, arching is easier. But connectors only see dc.

Reportedly issues in redundency logic and supporting circuits.

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Re: Indian Space Programme Discussion - Sept 2016

Postby chetak » 03 May 2018 12:21

Singha wrote:Its good . They are putting best people on it and serious about failure root causing


This sort of investigation is rather difficult because they would have to blindly investigate multiple causes. The evidence is, unfortunately, orbiting the earth.

They have the next best thing which is a similar system and that's on it's way back home.

But kudos to ISRO, its efficient and decisive management is a rarity in govt circles.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Vips » 03 May 2018 18:21

Fire breaks out at ISRO campus in Ahmedabad.

A fire broke out in the Space Applications Centre (SAC) at the ISRO campus situated in the Satellite area of Ahmedabad West on Thursday. Nobody was reported injured in the blaze.

Twenty five vehicles of the Ahmedabad Fire and Emergency Services (AFES) and ambulances were rushed to the spot to deal with the emergency situation.

"A major fire broke out at the research centre inside the sprawling SAC campus in the Satellite area of the city this afternoon. As many as 25 fire tenders have been pressed into service by the Ahmedabad Fire and Emergency Services [/u](AFES)," an AFES official said.

After being alerted about the incident, Additional Chief Fire Officer Rajesh Bhatt and other senior AFES officials rushed to the spot.
According to Bhatt, it would take a couple of hours to douse the flames completely.

"It will take another two hours to control the fire completely as thermocol sheets are still burning and emitting smoke. However, the fire has been brought under control and no one was injured," he said.

Ahmedabad District Collector Vikrant Pandey, who was also on the spot, said the blaze had engulfed the research centre building, that stood isolated.

"The fire will not spread to other buildings on the premises," he added.

"All our teams are at the site and it will soon be brought under control," Pandey added.

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Re: Indian Space Programme Discussion - Sept 2016

Postby ramana » 03 May 2018 21:44

chetak wrote:
Singha wrote:Its good . They are putting best people on it and serious about failure root causing


This sort of investigation is rather difficult because they would have to blindly investigate multiple causes. The evidence is, unfortunately, orbiting the earth.

They have the next best thing which is a similar system and that's on it's way back home.

But kudos to ISRO, its efficient and decisive management is a rarity in govt circles.



The fault tree analysis method quickly isolates the most likely causes and these can be further verified by on ground testing to identify the root cause.

Again root cause is the cause that by eliminating gets rid of the failure.

Likely causes will leave multiple corrective actions which may or may not fix the problem.

The fact they brought back the GSAT-11 for further testing means they know the most likely cause and even the root cuase.

Very good management decision making in practice.
A lesson for all of us even in daily lives.
Bash on regardless does not work in high consequnec situations
At same time excess caution is also not good.
"Dhairye Sahase Lakshmi!!!"

in English 'Fortune favors the brave!!!!'

And break a coconut just in case.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Vips » 05 May 2018 18:12

NFL to set up dedicated plant to supply 1000 tonnes of Di-Nitrogen Tetroxide per annum to ISRO.

NFL has bagged an order from ISRO to supply di-nitrogen tetroxide (N2o4) , Mishra said the company would set up a plant at Vijaipur in MP with an investment of Rs 350 crore. The annual capacity of this plant would be 1,000 tonnes. The company has received 'letter of intent' from ISRO on BOOS (built, own, operate and supply) basis.

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Re: Indian Space Programme Discussion - Sept 2016

Postby dinesha » 06 May 2018 15:27

China’s ‘Heavenly Palace’ & India’s Need For ‘Eyes In The Skies’

http://www.delhidefencereview.com/2018/ ... the-skies/

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Re: Indian Space Programme Discussion - Sept 2016

Postby vasu raya » 06 May 2018 19:39

These installations are at such vast places, and taking a cue from solar power enabled Cochin airport, most radars both mil and civilian that operate 24/7 can use solar power during peacetime

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Re: Indian Space Programme Discussion - Sept 2016

Postby Singha » 06 May 2018 20:18

i saw the vast solar farm of kochi airport this week on a tourism visit. the airport's old side terminal2 is the old 80s era AAI chic but clean and with very comfortable wooden well padded sofa chairs than the "modern" hard chairs. the Terminal3 looked new and modern, but did not go in. I dont know what terminal1 is - perhaps international flights.

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Re: Indian Space Programme Discussion - Sept 2016

Postby dinesha » 06 May 2018 23:18

ISRO’s clock to prop up India’s own GPS
http://www.thehindu.com/news/national/i ... 787959.ece

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Re: Indian Space Programme Discussion - Sept 2016

Postby prasannasimha » 07 May 2018 07:36

https://twitter.com/indiandefence11/status/993055514392068097/photo/1


According to recent updates, the Reusable Launch Vehicle (RLV-TD) of ISRO has undergone autonomous runway Landing with landing gear and low subsonic tests completed at IIT, Kanpur. Now a scaled-up version of RLV will be developed to carryout an Orbital Re-entry experiment.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Mort Walker » 07 May 2018 09:10

dinesha wrote:ISRO’s clock to prop up India’s own GPS
http://www.thehindu.com/news/national/i ... 787959.ece


+10^10

GPS satellites use cesium beam clocks. Very few space certified are on the commercial market. The next commercial option is a rubidium clock.
It is really a feat that ISRO has made a precise clock that is most likely an isotope beam clock. In doing so, they may have achieved something others have not and has significant commercial scientific applications.

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Re: Indian Space Programme Discussion - Sept 2016

Postby dhyana » 07 May 2018 11:28


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Re: Indian Space Programme Discussion - Sept 2016

Postby JayS » 07 May 2018 11:56

dinesha wrote:ISRO’s clock to prop up India’s own GPS
http://www.thehindu.com/news/national/i ... 787959.ece


How is that the particular Atomic clocks used for the IRNSS fleet are so terrible..? One Sat totally lost, three more have clock failures. That's 4 out of 7. That's very very high rate of failure for any space based system. Doesn't is look suspicious...? Is the particular clock used standard COTS clock for satellites..? If yes, does it show same rate of failures on other satellites as well out side India..? The situation is so dire that it forced ISRO to develop own Atomic clocks and the new planed 4 satellites will have desi Atomic clocks. A very good thing in long term for Desh. But the failure of the firang clocks looks rather suspicious to me. Unless its some new version of clock with some design flaw. In that case, ISRO should sue the company for recovery of the huge loss and delay in deployment of IRNSS.

OK. Did some googling. ESA's Galileo also uses same Ru clocks as ISRO's IRNSS, but they have 2 Ru + 2 Hydrogen based clocks per Sat. They also had failures. Made by Swiss company Spectracom.

https://defenceupdate.in/three-atomic-c ... tellation/

This news tells that ESA identified the issue behind the failures: https://phys.org/news/2017-07-europe-ga ... locks.html

"The main causes of the malfunctions have been identified and measures have been put in place to reduce the possibility of further malfunctions of the satellites already in space," commission spokeswoman Lucia Caudet said.

ESA found after an investigation that its rubidium clocks had a faulty component that could cause a short circuit, according to European sources.


So its the faulty clocks. In that case the supplier, the Swiss company Spectracom should be sued to recover losses by ISRO. But I suppose it doesn't work like that in the Space business.

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Re: Indian Space Programme Discussion - Sept 2016

Postby Prem Kumar » 07 May 2018 14:19

I still suspect hanky-panky. The failure rate is way too high. Plus we lost a satellite due to launch problems. May seem like independent incidents, each having its own root cause. But having seen American perfidy before (ISRO Nambi incident, Homi Bhabha death etc), I wouldn't rule anything out.

If NAVIC becomes fully operational, India might mandate NAVIC chips to be embedded in all phones + apps that are NAVIC compliant. 1.2 Billion people. A lot at stake for the massa.

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Re: Indian Space Programme Discussion - Sept 2016

Postby JayS » 07 May 2018 15:31

Prem Kumar wrote:I still suspect hanky-panky. The failure rate is way too high. Plus we lost a satellite due to launch problems. May seem like independent incidents, each having its own root cause. But having seen American perfidy before (ISRO Nambi incident, Homi Bhabha death etc), I wouldn't rule anything out.

If NAVIC becomes fully operational, India might mandate NAVIC chips to be embedded in all phones + apps that are NAVIC compliant. 1.2 Billion people. A lot at stake for the massa.


I would think Massa care much more due to the geo-political and Security implication of India having its own accurate SATNAV system for its Military (and the footprint of IRNSS would go up in future for sure from current India + 2000km radius), rather than the chips to be included in e-devices in it. Phones already come with received for 3-4 Nav systems now a days and a whole lot of Phones for India are just identical with the global markets. Shouldn't really be a big deal to add one more. Few cents per device at max.

Vips
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Re: Indian Space Programme Discussion - Sept 2016

Postby Vips » 14 May 2018 06:24

All tests on heaviest sat Gsat-11 to be over by May 17: Isro chief.

Indian Space Research Organisation (Isro) is currently doing a series of tests on its heaviest communication satellite Gsat-11 weighing over 5.7 tonne after recalling the same from the European spaceport to look for any "potential anomaly".

Talking to TOI, Isro chairman K Sivan said, "We are currently doing tests on Gsat-11 at our Bengaluru's ISRO Satellite Centre (ISAC). All tests, including test on its electrical circuits, are going to be over by May 17."

He said, "If we find no anomaly, then we'll proceed further and start discussions with officials of Arianespace for the next launch date. They have their own busy schedule and we have to start talks to fix a date for our satellite launch."

Isro postponed the launch of Gsat-11 initially planned on May 25 from the European spaceport as it did not want to take chances with its heaviest satellite especially after the signal failure episode with Gsat-6A. Communication satellite Gsat-6A, which was successfully launched from Sriharikota on March 29, got out of control during the third orbit-raising manoeuvre in space when the signal with the satellite got abruptly snapped because of suspected power failure. The space agency since then has been trying to restore the communication link with Gsat-6A though it knows its exact location through the satellite-tracking system.

High-throughput satellite Gsat-11, which carries 40 transponders in Ku-band and Ka-band frequencies, is capable of "providing high bandwidth connectivity" with up to 14 gigabit per second (GBPS) data transfer speed. The heavy-duty satellite is so massive that each solar panel is over four metres long, equivalent to the size of a room. The satellite will usher in high-speed internet connectivity, especially in rural India.

The chairman said, "Isro is simultaneously working on its next communication satellite Gsat-29. Its launch is due in June or July." Gsat-29, which carries Ka x Ku multi-beam and optical communication payloads for the first time, will be launched by second developmental flight of Isro's 'fat boy' GSLV-MkIII. The satellite mission targets for village resource centres in rural areas to bridge the digital divide.


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