With the successful launch on May 23 of the first technology demonstrator of the indigenously made Reusable Launch Vehicle (RLV), the Indian Space Research Organisation (ISRO) has taken a baby step in building a vehicle that can be reused multiple times to launch satellites into orbit. The hypersonic flight, that lasted about 770 seconds from lift-off to splashdown in the Bay of Bengal, reached an altitude of about 65 km before re-entering the atmosphere at nearly five times the speed of sound. Many more such successful launches have to be undertaken before the RLV becomes a reusable launch system to put satellites into orbit. Some of the objectives of this week’s launch were to test the aero-thermodynamic characterisation of the vehicle with wings when it re-enters the atmosphere at hypersonic speed; the control and guidance system; the control system to land the vehicle at a specific location; and the hot structure, the basic body-carrying part of the vehicle with heat protecting tiles. The ultimate objective is to test the vehicle’s performance when it travels at a speed of Mach 25 using air-breathing propulsion. It will take 10 to 15 years, and several more launches, before ISRO readies a reusable launch vehicle for commercial use.
Building a fully and rapidly reusable launch vehicle will play a pivotal role in cutting down by as much as 80 per cent the cost of launching satellites into orbit. In fact, ISRO is already well-known for launching satellites at a far cheaper cost than other space agencies. Currently, the bulk of the launch cost comes from building the rocket, which can be used just once. No other space agency has reusable launch vehicles in operation, and ISRO has taken a lead in developing one. Learning from the mistakes of the U.S. National Aeronautics and Space Administration (NASA) in its space shuttle programme, ISRO will not use the same reusable vehicle to launch satellites and carry astronauts as it drastically reduces the payload capacity and thereby increases the cost per kg. ISRO will also use cutting-edge technology to shield the launch vehicle from intense heat to reduce, if not completely eliminate, refurbishment expenses. Getting this right would enable the vehicle to be reused within a very short span of time. If all works as per plan, ISRO should be able to break even after 25 to 50 launches, bringing down the cost of further launches on the same vehicle.