BENGALURU: Just around the time Indian space scientists drew up plans to launch ‘Chandrayaan-I’, the orbiter to earth’s nearest astral neighbour early 2000, they commenced work on the Two-stage-to-Orbit (TSTO) spaceplane or reusable launch vehicles when Dr. K. Kasturirangan was at the helm at Indian Space Research Organisation (Isro).
On Monday, however, Dr Kasturirangan said irrespective of who commenced the RLV project, Dr A.S. Kiran Kumar, Chairman of Isro, and Dr. K. Sivan (Director, Vikram Sarabhai Space Centre (VSSC), Thiruvananthapuram), deserved all the praise for the first step towards development of a rocket which would facilitate low-cost access to space.
During his tenure as Chairman, Dr Kasturi-rangan had disclosed plans to design and manufacture such a vehicle by 2025, adding, “It is on the drawing board now.”
This at a time when they were grappling with problems plaguing the Geo-synchronous Satellite Launch Vehicle (GSLV) powered by cryogenic engines acquired from Russia.
They had initiated the design and development of an indigenous cryogenic engine as well as a semi-cryogenic engine for the next GSLV rockets.
And for satellites weighing more than four tonnes (beyond the launch capability of GSLV), preliminary studies commenced on a single stage to orbit (SSTO) reusable vehicle called AVATAR, a rather ambitious effort as it involved the use of air-breathing ramjet-scramjet engines in order to scale down the amount of fuel required for such a rocket.
Sources in Isro said as AVATAR was an ambitious programme because of the kind of engines and material technologies required, and therefore would be a long-drawn effort, space scientists decided to first develop a Two Stage to Orbit (TSTO) reusable launch system for the immediate future by utilizing its current capabilities and target development of AVATAR over long term mission management to land at a specified location and characterization of hot structures are planned to be demonstrated.. Besides cutting down on the cost of space transportation, such spaceplanes do not add to debris in space, thus reducing the possibility of satellites being hit by debris and resulting in damage and temporary loss of services provided by them.
Sources said all technologies essential for an operational RLV would be developed in phases through a series of experimental flights. The first in the series of experimental flights would be the hypersonic flight experiment (HEX) followed by the landing experiment (LEX), return flight experiment (REX) and scramjet propulsion experiment (SPEX). Reusable Launch Vehicle Technology Demonstrator Hypersonic Experiment (RLV-TD HEX1) wherein the hypersonic aero-thermo dynamic characterization of winged re-entry body along with autonomous mission management to land at a specified location and characterisation of hot structures were demonstrated during the first flight on Monday.
Spaceplanes do not add to debris
The concept of “Two-stage-to-orbit” spaceplane or reusable launch vehicles was initiated when Dr Kasturirangan was Chairman of Isro. He had disclosed plans to design and manufacture such a vehicle by 2025
Besides cutting down on the cost of space transportation, such spaceplanes do not add to debris in space, thus reducing the possibility of satellites being hit by debris and resulting in damage and temporary loss of services provided by them.
Meanwhile, in Bengaluru, space scientists won a round of applause from members of the Committee on subordinate legislation of Rajya Sabha, headed by T. Subbarami Reddy. The committee was in Bengaluru on a two-day visit and cheered the space scientists when an announcement was made about the successful flight of RLV.