Reusable Satellite Launch Vehicle (RSLV)

Recent news Item in TOI said that They intended impact landing of chandrayan1 into moon…any info on that?

Regds

here is our Chandrayaan-1

RajKhalsa:

The argument for RLVs is primarily economic. The cost of launching payloads in orbit is at least 10 times of what ISRO (and other satellite majors for that matter) perceive it should be in the long run. The RLV (especially, the one-step to orbit variety) is meant to achieve this objective of reducing launch costs by 1/10th.

Of course, there is also technological excitement about projects like these and spilloffs into other areas (for instance, in military or civilian air transport).

at 12 miles per second – the satellite ain’t never going to touch down – being that escape velocity from Equatorial Earth orbit is about 7 miles a second!!! 😮

http://hyperphysics.phy-astr.gsu.edu/hbase/solar/soldata.html#c1

A velocity of 100 miles per second is > escape velocity of the solar system which IIRC is around 75 miles per second.

Hi Sridhar

For a newbie, what are the advantages of a reuseable launch vehicle versus a one-shot one? Are they doing it simply for the benefit of research and development of the astronautics industry, or will there be a material (cost) benefit for this r&d?

The Frontline report above is a good, detailed one, but there is a set of errors. The errors relate to the speed of descent. It cannot be 100 or 12 miles per second. 100 miles per second or 160 km per second would imply that the satellite would descend from a low earth orbit within a second or two or even from a typical polar orbit of 900kms above earth to the surface in about 6 seconds – an impossibility.

Touchdown at 12 miles per hour seems reasonable. Touchdown at 12 miles per second on the ocean surface would essentially destroy the satellite. Just as a comparison, a typical commercial jet flies at about 500 miles per hour – which translates to about 0.14 miles per second. 12 miles per second is about 86.4 times the speed of a commercial jetliner!!!

BTW SRE and GSLV MkIII are in a sense connected, as SRE has its future connected with Indian’s in space. And thats what I heard from Indian Space Week organised by VSSC during the last month. The chap in there mentioned abt the SRE to the ‘poosiblity’ of the humans on GSLV MkIII, but did not clarify. But unfortunately I missed the seminar which was on the last day.

The RSLV if it is said has to be the recovery of the whole satellite lauhch vehicle or atleast the FIRST stage, as thats what cost the more,both in terms of time and cost of fabrication. So if a Lauch Vehicle has to be resused to best economically, its that first stage thats will have to be recovered. I feel thats wud only make any concept as resuable launch vehicle other than Space shuttle like stuffs, But we don have a huge budget to throw away any huge boosters after launching the vehicle thats can land on airfield after its mission. Though I may be wrong.

I clearly don’t know the details abt the RSLV, as I herad it in the regional news, which failed to get time on national news. Also is the fact that the Chairman’s report (and the French Spy case, for which CBI is in France for extradition) is not to be seen online. I though atleast u guys wud be able to dig it up.

well I guess it has now been designated as RSLV, as thats what been reported.

The Space Capsule Recovery experiment scheduled for next year is a step in that direction. The capabilities that experiment will develop are
a. Deboost from orbit
b. Re-entry (including the heat shield required for the purpose)
c. Controlled deceleration
d. Recovery

The a small scale SRE has already been done …. the same was also shown on DD news

———————————————-
A successful recovery

T.S. SUBRAMANIAN
in Sriharikota

The test conducted over the Pulicat lake signals that the Indian Space Research Organisation is on track to launching the Space Capsule Recovery Experiment, which will enable India to join a select group of countries with the knowhow.

AS the helicopter circled at a height of 5 km over the Pulicat lake, off Sriharikota island in Andhra Pradesh, the spectacle that unfolded was stunting. A contraption dropped out of the helicopter and a parachute spread out from it. Moments later, another parachute opened and swayed in the wind. Finally, a third parachute, bright orange in colour, unfolded, and from it dangled a “till-box” (capsule) weighing about 500 kg. As the winds gusted over the vast expanse of the lake, the parachute swayed back and forth, and quietly touched down on the dry lake-bed.The parachute and the capsule were recovered quickly by Indian Space Research Organisation (ISRO) teams.

The “till-box” coming down over the Pulicat lake.

The air-drop experiment, held on August 19, signalled that ISRO is on track to launching a recoverable satellite next year on board the Polar Satellite Launch Vehicle (PSLV).

The operation began around 6.30 a.m. A number of camera stations belonging to ISRO had been set up on the road from Sullurpeta to Sriharikota, which cuts through the waters of the lake.

As the helicopter took off from Sriharikota, a cameraman’s walkie-talkie erupted into life. “The SRE [Space Capsule Recovery Experiment] monitor has been connected to the helicopter. Any moment it can take off,” a voice alerted the cameraman. In a few moments, the helicopter was air-borne. It flew in a huge circle over the lake. As it completed the second circle, it dropped the till-box.

This was the third test over the lake and all were successful. The previous two were conducted on June 23 and 28. ISRO had earlier conducted air-drop tests of the capsule several times over land near Agra in Uttar Pradesh. The next recovery experiment, from the sea, is scheduled to be conducted in a few months’ time.

THE recoverable satellite is to be called SRE. The satellite will stay in space for many days, and its payloads will be used to conduct micro-gravity experiments. ISRO has selected experiments in quasicrystal growth and biomemetic material synthesis. The SRE is to land in the Bay of Bengal and to be retrieved by Coast Guard ships. It will have ultra-high frequency beacons, floatation systems and water dyemarkers to aid its recovery.

India will join a select club of countries when it launches a recoverable satellite. Only the United States, Russia, the European Union and China possess this frontier technology. A recoverable satellite has to be de-orbited and protected from intense heat when it re-enters the earth’s atmosphere. To prevent the satellite from being destroyed, it has to be coated with composites. It should also have closed loop guidance and control systems.

The SRE is to fall into the Bay of Bengal within a specified area. The speed of the descent should be staggered. The three parachutes should deploy with milli-second accuracy.

The SRE will help cut down costs because the systems retrieved can be reused. Besides, they are crucial to ISRO’s plans to build a reusable launch vehicle (RLV). A technology demonstrator of the RLV will be flight-tested in 2008. The RLV’s booster and upper stages will fall into the sea and will be recovered to be used again. The vehicle itself will taxi to a halt like an aeroplane on the runway of one of the Indian Air Force’s (IAF) aerodromes.

ACCORDING to Dr. B.N. Suresh, Director, Vikram Sarabhai Space Centre (VSSC), Thiruvananthapuram, ISRO “got all the data” from the latest test. “All the results were as expected. There was no problem anywhere. The data are promising. We are in the process of getting into the details of sea recovery,” he said.

The VSSC designed the capsule and manages the project. The Satish Dhawan Space Centre at Sriharikota looks after the capsule recovery operations. The IAF provides the helicopters. The Aerial Delivery Research and Development Establishment (ADRDE), Agra, provides the parachutes. ISRO’s Telemetry, Tracking and Command Network plays an important role as well.

The Pulicat tests were meant to check the terminal phase of the descent. They were qualification tests to check the deployment of the parachutes. “This is basically mission-level testing to check all the critical operations,” Suresh said. The critical operations included de-orbiting the satellite through propulsion after its payloads had done their experiments, then making it enter the atmosphere with the closed loop guidance and control systems, and making it soft-land on the sea within a small area. For this, atmospheric and wind disturbances should be contained. “You are basically bringing down the velocity step by step from the orbital velocity to touch-down velocity,” Suresh said.

The VSSC engineers connected with the SRE explained that parachutes were an important means of breaking the descent of the satellite. The parachutes form an important component of the terminal phase of the flight from a height of about 5 km. “Our aim is to reduce the speed of the descent from 100 miles [160 km] a second to 12 miles [19.2] a second. The main parachute can land safely on the sea surface at 12 miles a second and can be recovered,” said an engineer. To reduce the speed in stages, three parachutes are deployed in sequence. First a small parachute opens, then a drop chute unfolds, and finally the main chute gets into action. When the drop chute is in action, the descent speed of the recoverable satellite is reduced from 100 miles a second to 50 miles a second. The main parachute further reduces it to 12 miles a second to cushion the impact of the landing at sea.

The SRE has four major hardware elements: aerothermo structure; spacecraft platform; deceleration and floatation system, and payloads for conducting experiments in micro-gravity. There will be flight electronics on board the satellite. Triggering systems will deploy the parachutes one after another at precise intervals. The flight electronics will sense the altitude and deploy the parachutes. The parachutes, pyro-devices, avionics packages of triggering units, telemetry and tracking systems, sensors for measuring the altitude and so on are placed inside the capsule (satellite). The floatation system will keep the satellite afloat. Its beacons will signal that it has landed. Dyemarkers will make it visible.

LInk

To be fair to ISRO they have built up pretty impressive capabilities on a shoe string budget and in a resonable time frame inspite of all the initial hiccups. Nothing to suggest that they wont able to do the above in the time period specified.

Hi,

… yes u guys heard it right ….. just 2day got to hear from ISRO Chairman that India’s RSLV would be ready by 3-4 years.

The 3-4 years time is stated for the completion of the RLV-TD, Technology Demonstrator.

What part of the word ‘unmanned’ is hard to understand? Let me quote what I had said again

The ISRO RLV will be a small, unmanned craft.

As for launch capabilities of ISRO, google for GSLV and PSLV and you would get full details on launch capabilities of ISRO.

The RLV that the ISRO Chairman is talking about will be a technology demonstrator. Also, it won’t be a one-stage to orbit vehicle, but a two-stage to orbit vehicle (i.e. it will not take off like a plane – rather it will be launched by a rocket booster and land like a plane at a runway).

The ISRO RLV will be a small, unmanned craft that will help develop the capabilities for full-scale launchers later on (including a one-stage-to-orbit launcher much later on). The Space Capsule Recovery experiment scheduled for next year is a step in that direction. The capabilities that experiment will develop are
a. Deboost from orbit
b. Re-entry (including the heat shield required for the purpose)
c. Controlled deceleration
d. Recovery

The fourth capability (recovery) is not directly applicable to the RLV since the capsule will be slowed by a parachute and will have a soft landing on sea. The RLV on the other hand will be required to glide to a runway. However, the first three capabilities will be applicable to the RLV.

SO in all likeness to Spacecraft Challenger but smaller??? 😎

Well such a program if it still exsist must cost a heck of a lot of money not to mention the R&D put into developing the astronaughts to fly it!

If the program can assume operational in 3-4 years would mean india already have the means, IE the rocket with enough boost to lift such a payload!

I think they are just too optimistic about it… after all it took everone else so much time just to put someone into space. 🙁

The RLV that the ISRO Chairman is talking about will be a technology demonstrator. Also, it won’t be a one-stage to orbit vehicle, but a two-stage to orbit vehicle (i.e. it will not take off like a plane – rather it will be launched by a rocket booster and land like a plane at a runway).

The ISRO RLV will be a small, unmanned craft that will help develop the capabilities for full-scale launchers later on (including a one-stage-to-orbit launcher much later on). The Space Capsule Recovery experiment scheduled for next year is a step in that direction. The capabilities that experiment will develop are
a. Deboost from orbit
b. Re-entry (including the heat shield required for the purpose)
c. Controlled deceleration
d. Recovery

The fourth capability (recovery) is not directly applicable to the RLV since the capsule will be slowed by a parachute and will have a soft landing on sea. The RLV on the other hand will be required to glide to a runway. However, the first three capabilities will be applicable to the RLV.

India has a rocket to launch how large a payload???

did they publically announce it ???

can someone show me some stats on it? please?