At 11:25AM today, India’s Defence Research and Development Organisation (DRDO) conducted the first on-field test of its ambitious project to build a hypersonic unmanned scramjet cruise missile. The Hypersonic Technology Demonstrator Vehicle (HSTDV) has been in the making for a very long time, and today marked the first real-world test of the hypersonic vehicle using a reusable solid booster first stage.
The significance of the HSTDV is enormous on both security and technological grounds. Security-wise, a hypersonic cruise missile can be key in taking out hostile airborne attacks, giving the Air Force an edge in terms of launching offenses of their own. It is also a technological feat that can be incorporated into other areas such as sweeping surveillance tasks, all the while being energy efficient in operation.
This is where the technology comes in. The HSTDV is an unmanned scramjet, designed to eventually reach production target of Mach 6.5 (2,229.5 metres per second) speeds at an altitude of 32,500 metres. This would give the cruise missile a total flight impact distance of nearly 45km, within impact time of just 20 seconds. The key areas of technoogical emphasis in this project include hypersonic propulsion, wind transmission with minimal drag loss, enhancing aerodynamics, and refining the scramjet engine.
The HSTDV uses a solid rocket launch booster for initial propulsion, following which combustion takes place in the anterior scramjet engine. The engine takes in an inflow of air particles, and compresses them inside a combustion chamber without slowing them down, thereby producing thrust that is further helped along by the side fins that aerodynamically amplify the thrust. It is this mechanism that is deemed imperative in giving the cruise missile hypersonic speeds. The double-wall engine is built using a Niobium alloy, which has a high thermal latency, and can therefore withstand the high combustion temperature and pressures inside the engine chamber.
While this is only the prototype design, DRDO engineers have stated before that they intend to test the HSTDV at up to Mach 12. Assuming that impact range remains constant, the HSTDV will increase its impact range by 1.8x, if such speeds can be achieved. This will be a new straw in the hat for India and its quest for equipping its offensive and defensive arsenal with ballistic cruise missiles. A weapon to the tune of the HSTDV can be lethal even in non-warfare cases, and the technology itself can be path-breaking.
If the combustion model is harnessed, it may, in fact, lead up to commercial usage designs, which in turn can aid areas such as reusable spaceflight and more efficient commercial cargo transmission. The first test has been claimed to have been a success by DRDO officials, as per radar data, marking a successful start to the quest for hypersonic engineering that began nearly two decades ago.