ISRO General News and Updates

[Haldiram]

Firstly, rockets are too heavy to be decelerated with parachutes!
Secondly, parachutes do let the cargo 'impact' on the ground - undesirable for reuse of looooong rockets that might just disintegrate.
Thirdly, if the parachute just drops it in the ocean, how will you recover it from the ocean bed?

The same way they recover heavy capsules, by making them fall in the water and then using a ship to bring them onboard.

NASA did it with ARES where they recovered a reusable rocket using parachutes.

https://www.technologyreview.com/s/416513/analyzing-the-flight-of-ares-i-x/

This concept design is from the French space agency : http://cosmiste.blogspot.com/2014/01/

From 1979 to 1981, CNES, the french space agency, and ESA made a deep study to use a set of parachutes in order to slow down the first stage's fall into the Atlantic Ocean. Cutting cost on launch operation was seen as critical for Europe at that time. The Space Shuttle was about to make its first flight and this new spacecraft was to slash launch cost. The fear of ESA was that all commercial satellite operators would leave the Ariane order book in favor of the space shuttle one, leaving few governmental flight for the European rocket with pricey launches as a consequences.

 

[Enquirer]

The same way they recover heavy capsules, by making them fall in the water and then using a ship to bring them onboard.

NASA did it with ARES where they recovered a reusable rocket using parachutes.

https://www.technologyreview.com/s/416513/analyzing-the-flight-of-ares-i-x/

This concept design is from the French space agency : http://cosmiste.blogspot.com/2014/01/

Rockets are heavier than the crew capsules (which are not reused anyways!)
Someone experimented something several decades ago but it was never implemented...that should give everyone a reason not to go that way...

 

[Haldiram]

Rockets are heavier than the crew capsules (which are not reused anyways!)
Someone experimented something several decades ago but it was never implemented...that should give everyone a reason not to go that way...

There's evidence of that being used earlier, you probably overlooked the 5 pictures of heavy rockets above. They had to shelve those plans due to resource crunch during the cold war era. You've made your opinion heard, if you don't agree, step aside, don't make everything a penis measuring contest.

 

[Enquirer]

There's evidence of that being used earlier, you probably overlooked the 5 pictures of heavy rockets above. They had to shelve those plans due to resource crunch during the cold war era. You've made your opinion heard, if you don't agree, step aside, don't make everything a penis measuring contest.

The only one concerned about his penis size seems to be yourself! I merely gave a factual scientific explanation - seems like you couldn't stomach it without your manhood shrinking like a tortoise??

Like all illiterate fanboys you too see some pretty pics and assume the world without spending few minutes to read the accompanying text!!

The description clearly says that the experiment was conducted once to study the forces etc. The only thing that failed in the experiment was the proper opening of the parachutes!

Secondly, the French agency never experimented - it was only a concept in their heads!!!

If you can show that a rocket was recovered using parachutes and then subsequently put into use again, then speak or else go look for your vanished penis!

 

[Indx TechStyle]

Does it lower the overall cost of the launch to have a vertical landing rocket, instead of just having a parachute assisted descend and then recovering that module to be reused later? (seems like the latter will consume less fuel, isn't it?)

Parachutes or more likely there'll be retro thrusters.
In any expendable launcher, you waste entire set of stages and payload fairing bus, most of which can be recovered.
May be first stage will land back and others will land in Ocean.

Thirdly, if the parachute just drops it in the ocean, how will you recover it from the ocean bed?

It gonna depend upon shape & density too. Obviously, there's no point if it sinks. It's not clear what they gonna do. So, I won't comment either.



They are going to carry out a landing experiment by dropping it from helicopter this year. Let's see ourselves instead of arguing.

 

[Advaidhya Tiwari]

It gonna depend upon shape & density too. Obviously, there's no point if it sinks. It's not clear what they gonna do. So, I won't comment either.



They are going to carry out a landing experiment by dropping it from helicopter this year. Let's see ourselves instead of arguing

There are examples of parachute landing which have been regularly carried out in military vehicles -

Similar concept with some cushioning lke airbags while landing or some structural hardening in the side to land along with the relative softness of water surface can be used for landing rockets

 

[Enquirer]

There are examples of parachute landing which have been regularly carried out in military vehicles -

Similar concept with some cushioning lke airbags while landing or some structural hardening in the side to land along with the relative softness of water surface can be used for landing rockets

See if you can apply principles of physics to see if the technique will work on large rockets.
I am too tired to explain basics.....

 

[Flame Thrower]

There are examples of parachute landing which have been regularly carried out in military vehicles -

Similar concept with some cushioning lke airbags while landing or some structural hardening in the side to land along with the relative softness of water surface can be used for landing rockets

Add additional payload while takeoff for cushions!?

Parachute is the worst way of recovery. It is susceptible strong winds.... It has to happen on land only else floatation devices weight should also be added.

Give that takeoff happens close to sea or oceans, additional fuel to guide the rocket towards land will increase the weight even more.

Do you know that SpaceX hasn't painted it's first stage as the weight and cost is increasing.

I'd say that SpaceX's reusability is good.

Thus I rest my case

 

[happylion]

The role of a reconnaissance satellite is for repeat sampling many times a day to detect differences. Cannot doreal time monitoring(for eg construction and HYSiS type of satellite can detect variation in dug up earth top soil dispersion or alteration) (cannot penetrate significantly through earth) For that we need long endurance drones , aerostats masts etc

As far as parachutes wrt rockets are concerned ISRO plans to use the parachute to help deceleration ,reorientation and to help bagged landing- these concepts have been included as option in ISRO's TSTO /RLV program

There are two groups in ISRO - one wanting to have winged body as first stage and the other blue origin/space X type first stage landing.with second stage opposite of the first (these were not the first to attempt vertical landing though) Both options are being explored and studied.

 

[happylion]

The HEX experiment is one of the few(in fact if I am right the first) with the winged body directly on the first stage with reentry at hypersonic speeds (actual experimnents) .unlike the piggy back space shuttle.

 

[happylion]

One small note is that one of the Indian satellites can take a swath video for s a short time (I think 4 minutes) over a spot of interest.
As far a imaging capability of Indian satellites goes what the grape vine says is that the resolution of military grade images is far higher than the declared civilian grade images.

 

[Haldiram]

The HEX experiment is one of the few(in fact if I am right the first) with the winged body directly on the first stage with reentry at hypersonic speeds (actual experimnents) .unlike the piggy back space shuttle.

If memory serves me right, reusable launch was one of Abdul Kalam's pet project, isn't it? This was way back in 1973 when Kalam and K.Sivan joined ISRO (later Kalam left for DRDO). I think they illustrated 2 versions, one was the something like using a hypersonic jet plane to launch the satellite like launching a missile and after launching, the plane could land like a normal plane. Zero fallout. This is not like the SpaceX version which lands vertically down. It's a fully functional space vehicle that goes up, puts the payload into orbit and comes down.

The other was the parachute recovery model which was later started after Kalam left for DRDO.

Some part of it finds partial mention in the vision document from Kalam's blog : http://abdulkalam.nic.in/sp280705-6.html

There would be parachute on the top and there was an airbag cushion like thing being built for the launch vehicle to land on hard surfaces, something like this :

 

[Indx TechStyle]

The ISRO Tender Notice With Fascinating New Details of Gaganyaan
Two new semi-cryogenic core stages, a new variant of the cryogenic upper stage and an augmented second launchpad at Sriharikota to prepare for a launch vehicle to lift more than before.

The Indian Space Research Organisation (ISRO) has provided more details about its Gaganyaan programme, including new stages for its GSLV Mk III launch vehicle, through – of all things – a tender notice. Such surreptitiousness is par for the course for India’s spaceflight organisation, which has often done next to nothing to publicise even its most high-profile space missions.

According to Google’s timestamp, the notice has been available online since at least August 2017; another version was online on January 25. In it, ISRO has invited quotations for a slew of infrastructure upgrades that will prepare its second launchpad (SLP) at the Satish Dhawan Space Centre, Sriharikota, to support a rocket that can lift humans to space, as well as heavier satellites. The last date to submit proposals is listed as February 20, 2019.

Perhaps the more tantalising details concern two rocket stages, called SC120 and SC200. The Mk III is a three-stage rocket. The first stage comprises two boosters called S200 attached to the sides of the rocket. The second stage is powered by the L110 stage, powered by liquid propellants combusted by a pair of Vikas 2 engines. The ‘S’ and ‘L’ denote solid and liquid, and the numbers denote the total propellant mass they carry.

The third stage is powered by a cryogenic engine, C20. The stages are ignited in the order of their numbering.

The GSLV Mk III. The crew module (as used in the atmospheric reentry experiment in December 2014) is visible in the topmost chamber. Credit: ISRO

The SC in ‘SC120/200’ stands for semi-cryogenic, a type of engine ISRO had already been developing for its reusable launch vehicle programme. Both of them seem to be alternatives for the Mk III rocket’s second stage, the L110.

A discussion on Reddit suggests adapting the GSLV Mk III to be able to use them would require enough changes for the modified version to differ significantly from the original. Such a rocket is then expected to be able to lift over 5,000 kg to the geostationary transfer orbit – a goal that former ISRO chairman A.S. Kiran Kumar spelled out in 2017. With the L110, the Mk III can currently lift up to 4,000 kg.

According to a technical document describing the trailer system used to transport rocket stages, the SC120 stage will be 4 m wide, 17.29 m tall and weigh 11,500 kg. A more futuristic variant is likely to see the SC120 replaced by the SC200 system. Using both together would be infeasible because of their combined weight.

The tender notice also describes a new and heavier cryogenic upper stage called C32, a variant of the C20 engine that the Mk III uses at present. In the Indian space programme, a rocket stage powered by a cryogenic engine carries liquefied oxygen and liquefied hydrogen, a combination shortened in industry parlance as hydrolox. The C32-powered upper stage, according to the transport system specs, will be 4 m wide, 14.75 m long and weigh 7,400 kg, which is 400 kg more than the C20.

The stage with the semi-cryogenic configuration will carry liquefied oxygen and a highly refined form of kerosene called RP-1 – a.k.a. kerolox. Kerolox has a lower specific impulse than liquefied hydrogen. Specific impulse is a measure of “how much more push accumulates as you use that fuel” (source).

However, to its significant credit, RP-1 is 10-times denser, which means the same volume of kerolox will generate more thrust than the same volume of hydrolox (same source: thrust is “the amount of push a rocket engine provides to the rocket”). RP-1 is also cheaper, more stable at room temperature and presents much less of an explosion hazard. A well-known launch vehicle that uses kerolox is the SpaceX Falcon 9.

Additionally, kerolox engines are harder to ignite than hydrolox engines, more so when the propellant flow rate increases as the engine fires for longer. As a result, they are sometimes ignited on the ground itself, where the process can be better controlled. This is unlike the L110 engine, which switches on over 110 secondsafter liftoff.

Beyond the crewed spaceflight programme itself, ISRO will need to continue its march to a heavier lift launch vehicle. Many commercial satellites and India’s own GSAT communication satellites are starting to weigh near 7,000 kg, especially as the latter is tasked with bringing more transponders online to sate India’s growing bandwidth demand.

India currently relies on launch vehicles operated by the French company Arianespance, such as its Ariane 5 rocket, to launch such heavy missions. These contracts are very expensive (over Rs 400 crore per launch). On the other hand, using a homegrown and home-operated vehicle is likely to provide better control over the expenditure, support local manufacturing and keep vehicles ready as and when necessary.

Moreover, ISRO has a programme-wise approach to science missions, which means it typically announces opportunities based on the availability of launchers in the future, and not the other way round. In this paradigm, having a heavier lift launch vehicle, akin to China’s giant Long March 5, will present correspondingly greater opportunities to India’s scientific workforce.

At the same time, it is also important that ISRO undertake launches more frequently. This isn’t something the Mk III can help with because – unlike the Polar (PSLV) and Small Satellite Launch Vehicles (SSLV) – it is a much more complex machine, and will be even more so in the SC120/200 configuration. It can’t be setup and launched with as much ease.

This in turn requires a launchpad able to support such an intense workload, together with the logistical requirements for transporting and loading different fuels. As the notice states (lightly edited):

For servicing of semi-cryo stage at the SLP, it is necessary that new facilities and/or augmentations are established apart from augmentation of existing cryo and gas systems together with associated instrumentation and control systems.

1. Isrosene system

2. Liquid oxygen storage and filling system (LOFS)

3. Nitrogen storage and filling system (NSS)

4. Gas storage and servicing system (GSSF)

5. Instrumentation and control systems

6. Cable trench and pipe trench

7. Augmentation of [liquid oxygen] storage at SLP,

etc.
(Isrosene is a grade of kerosene that ISRO has developed as a ‘greener’ fuel to be used on future missions.)

Proposed layout of the augmented SLP. Credit: ISRO

A launchpad upgraded in this fashion will also be useful for the reusable launch vehicle programme, expected to be ready by 2030. Its current design envisages a launch vehicle powered by four or five kerolox semi-cryogenic engines during its ascent (and a scramjet engine during the descent phase).

 

[Indx TechStyle]

From tender:

SDSC SHAR, the Space Port of India provides the world class launch base infrastructure for integration and launching of Indian Satellites and Foreign customer Satellites. ISRO’s Space Transportation Systems (STS) has approved the induction of Semi-Cryo stages SC120/SC200 & C32 Cryo Upper stage to meet GSLV Mk-III vehicle variants, which can achieve a target GTO payload of 5-5.5 tons. Towards this SPAC committee has approved Augmentation of SLP Project for Semi-Cryostage (ASLP) to be realized in 30 months at SLP SDSC SHAR. This Project has a major & unique challenge of realization matching with that of Semi-Cryo Stage development and not impairing the increased Launch Schedules from SLP. The Semi-Cryo stage will make use of SE2000 engine For servicing of semi cryo stage at SLP, it is necessary that new facilities/Augmentations are established apart from augmentation of existing cryo and gas systems together with associated instrumentation & control system. 1)Isrosene system 2)Liquid Oxygen Storage & filling system 3)Nitrogen Storage & filling system(NSS) 4)Gas storage & servicing system(GSSF) 5) Instrumentation and control system. 6) Cable trench and pipe trench 7)Augmentation of LOX storage at SLP and PH and electrical works etc.

https://www.isro.gov.in/sites/default/files/tenders/pt24-16-10202.pdf

 

[porky_kicker]

From tender:

https://www.isro.gov.in/sites/default/files/tenders/pt24-16-10202.pdf

You will like it

Isro plans on manned lunar mission

 

[Indx TechStyle]

You will like it

View attachment 31399

Isro plans on manned lunar mission

I guess I've seen it way back. Things simply aren't going to be that fast to land humans on moon.
Although, we'd have detailed plans for space station soon.
https://defenceforumindia.com/forum...eflight-program-hsp.77569/page-8#post-1473005
More:
https://indianexpress.com/article/t...an-interview-habitation-on-moon-mars-5545632/

 

[happylion]

That is a very old presentation and is a timeline of planned events

 

[SmilingBuddha01]

A thought just came to my mind, whether we can use the burnt out upper stage of PSLV C44 as an ASAT weapon in a latter date after keeping it in a dormant position for some time.
Is it possible to guide it to a Chinese military satellite and collide with it at our chosen time?

Sent from my Redmi Y2 using Tapatalk

 

[porky_kicker]

Another interesting pic from isro

 

[Indx TechStyle]

Is it possible to guide it to a Chinese military satellite and collide with it at our chosen time?

It is, though ASAT missile based on interceptor would be a faster way.