Technology
ISRO launches reusable launch vehicle
ISRO successfully launched the first technology demonstrator of the indigenously made Reusable Launch Vehicle (RLV), capable of launching satellites into orbit around earth and then re-enter the atmosphere. The RLV-TD HEX-01, a small-scale model, was launched from Sriharikota at 7AM and completed all required flight tests. The data from the test will now be used to create a full scale reusable launch vehicle.
A brief introduction to the RLV-TD
The RLV-TD is a 6.5 meter long aeroplane-like spacecraft weighing 1.75 tonnes, developed indigenously by the Thumba-based Vikram Sarabhai Space Centre, over 5 years, at a cost of Rs.95 crore. It is a scale model and is 6 times smaller than the final version, which ISRO estimates will take 10-15 years to develop. It is the first ISRO spacecraft to have delta (triangular) wings.
The only space shuttles in history
The only operational space shuttles were made by America and Russia, all of which are now out of service. Apart from these two nations, France and Japan had made some experimental flights, but the shuttles never went into operation.
The RLV-TD's mission
The purpose of the experiment is to test the capability of the RLV-TD to survive re-entry at speeds much higher than the speed of sound. A special rocket booster will hoist the RLV-TD to around 70 km above the atmosphere. The RLV-TD, with the help of small thrusters, will then be guided on to a virtual runway in the Bay of Bengal.
Materials used in the RLV-TD's construction
The RLV-TD has to survive temperatures of 5000-7000 degrees Celcius during its re-entry into the earth's atmosphere. The scientists at VSSC developed lightweight heat-resistant silica tiles to protect the RLV-TD's body from the searing heat and keep interior temperatures cool. The nose cone, which takes the brunt of the heat, is made up of a special carbon-carbon composite that can withstand very high temperatures.
Kalpana Chawla's death
Indian-born American astronaut Kalpana Chawla's death was a result of failure of the thermal coating on the American space shuttle Columbia. As a result, ISRO has placed a lot of emphasis on the thermal coating of the RLV-TD.
The implications of the RLV-TD's success
Although major space faring powers discarded the idea of a winged reusable launch vehicle, ISRO's scientists believe that a winged reusable launch vehicle would drastically lower the cost of launching satellites into space. According to their estimates, if the RLV-TD succeeds, the cost of sending stuff into space could be reduced by as much as 10 times, down to $2000 per kg.
The current cost of sending stuff into space
According to NASA, it currently takes $10,000 to put a pound of payload into Earth orbit. In kg terms, that's a bit over $22,000 or Rs.14.73 lakh per kg of stuff that has to be sent into space.
ISRO to test its maiden reusable space shuttle
India's spaceport at Sriharikota in Andhra Pradesh is set to witness the launch of ISRO's first indigenously made space shuttle. The Reusable Launch Vehicle - Technology Demonstrator (RLV-TD), as it is called, is scheduled for launch before the end of May 2016. ISRO will attempt to launch the RLV-TD into space and glide it back onto a virtual runway in the Bay of Bengal.
