The test flight of the RLV-TD on Monday represented the first step towards the ISRO programme to master the reusable launch vehicle technology.
Termed the Hypersonic Flight Experiment, it was the first of a sequence of four test flights to validate various technologies. Designed and developed by Vikram Sarabhai Space Centre (VSSC) at a cost of Rs. 95 crore, the RLV-TD weighing 1.75 tonnes used a thermal protection system (TPS) including 600 heat-resistant silica tiles and a Carbon-Carbon nose cap to withstand the high temperature during atmospheric re-entry.
The first Indian aircraft structure to fly up to Mach 5, the double delta wing RLV posed a challenge for VSSC engineers to manage the high instability of a winged body mounted on a booster rocket during launch. The design of the air frame, development of mono propellant thrusters for guidance and control and advanced avionics for mission management were other challenges.
The new developments for RLV-TD include the composite movable fin, flush air data system to measure the surface pressure on the aircraft, onboard computer, high resolution data acquisition system, lithium ion battery, patch antennas and radar altimeter.
As many as 600 engineers from ISRO centres, National Aerospace Laboratories, IITs and Indian Institute of Science were involved in the development of the RLV-TD over a period of eight years.