Space
Aviation Week & Space Technology Apr 12 , 2010 , p. 36
Frank Morring, Jr.
Bengaluru, India
Neelam Mathews
Bengaluru, India
New cryogenic engine, capsule flight tests must precede first Indian human spaceflight
Printed headline: Steps To Orbit
India is moving steadily toward sending its first astronauts to orbit on indigenous spacecraft, but it is taking a “stepwise” approach and has not yet committed funds to human missions, according to the new chairman of the Indian Space Research Organization (ISRO).
Instead, India’s human spaceflight program is funded for a four-year development and test effort that will build and fly an unmanned capsule to test its crew environmental control and life support system (Eclss) and launch-escape system, says K. Radhakrishnan, who became ISRO chairman Oct. 31, 2009.
Flying a two-person crew will also require development of a new cryogenic upper-stage engine for the upgraded Geosynchronous Satellite Launch Vehicle (GSLV Mark III) now in development. ISRO is on the verge of becoming only the fourth space agency to develop and fly a cryogenic upper-stage engine (AW&ST March 29/April 5, p. 18). But the staged-combustion engine set to fly this month will be followed by a more powerful gas-generator cryogenic engine for human-rated flights.
If development work goes well, ISRO will seek funding for manned tests of the vehicle on the GSLV. Although the 2.5-meter-dia. (8.2-ft.) capsule is being designed for three crewmembers, initial flights will carry two astronauts.
“We will first make this unit with an Eclss system, and will have a few unmanned flights of this module before we actually put a human being inside, initially monitoring the conditions, et cetera,” Radhakrishnan told Aviation Week at ISRO headquarters in this city, formerly known as Bangalore.
The first unmanned flight will lift off on a Polar Satellite Launch Vehicle (PSLV), followed by a test on the GSLV-D3 with India’s new indigenous cryogenic upper-stage engine.
“That is the one that is now getting funded,” the ISRO chairman says. “Then it will be followed by the others. . . . We are asking for them in phases.”
The initial four-year effort is funded at Rupees 12,400 crore ($2.8 billion), Radhakrishnan says.
The first GSLV-D3 is scheduled to launch the third week in April with the GSAT-4, a Ka-band testbed that will also carry an experimental GPS-augmentation payload. The human-rated vehicle will fly on the planned GSLV Mark III, which will use two new S200 solid-propellant strap-on boosters generating almost 500 metric tons of thrust each, and an upper stage with the planned gas-generator (GG) cryogenic engine.
“Because it is a GG cycle, we are able to test each element separately,” says Radhakrishnan.
The new cryogenic engine will be designed to generate 20 metric tons of thrust, almost three times the power of the staged-combustion cryo engine set to fly on the GSLV-D3 this month. That engine performed well in static testing, as did the S200 (AW&ST Feb. 22, p. 18). However, a 200-sec. long-duration test for the Mark III vehicle’s L110 core stage on March 5 halted after 150 sec.—its nominal duration on the GSLV D-3—because of “a deviation in one of the parameters,” says ISRO.
That anomaly is still being analyzed, and the continuation of the static-test series for the L110 stage at ISRO’s Liquid Propulsion Systems Center is on hold. The stage carries two hypergolic-propellant Vikas engines, which power both the GSLV-D3 and the PSLV.
“Another two years—that is our target—we should start integrating the vehicle and testing,” the new ISRO chairman says.
The human spacecraft will consist of the capsule, with a 14-deg. cone, and a service module containing five 414-newton (93-lb.-thrust) engines and a 3-4-kw. power system drawing on two rectangular solar arrays. Much of that technology will be based on systems already developed for India’s growing fleet of communications and Earth-resources satellites, according to T.K. Alex, director of the ISRO Satellite Center, which is doing much of the work on the manned vehicle.
The capsule will be protected from the heat of reentry by silicon ceramic tiles tested on the Space Recovery Experiment (SRE) in 2007 (AW&ST Jan. 29, 2007, p. 17). Like the SRE, the human capsule will splash down in the ocean for recovery by the Indian navy, which gained experience with the testbed, Alex says.
Astronaut selection has not started, although planning is underway for an astronaut training center here. In designing the center and its training regime, ISRO plans to draw on the experience of Indian cosmonaut Rakesh Sharma, a retired Indian air force officer who visited the Soviet Salyut 7 space station in a Soyuz capsule in 1984 to become the first Indian space traveler.
The center will include a centrifuge purchased abroad, and a neutral buoyancy tank to train for microgravity operations. India is working on a spacesuit for use inside the capsule in case of loss of pressure, but extravehicular activity capability is not currently planned. Alex says most Eclss technology—gas-handling and scrubbing—is not new to India, so developing the system will largely be an engineering task.
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