ISRO Set to Test Air-Breathing Hypersonic Technology on July 22
The Indian Space Research Organisation (ISRO) is gearing up for an exciting milestone on July 22, 2024, with the test flight of a groundbreaking air-breathing propulsion system. This innovative technology, designed to enhance rocket efficiency and reduce launch costs, will be launched from the Satish Dhawan Space Centre in Sriharikota at approximately 7:30 AM IST. This test marks a significant step forward in ISRO's journey towards more efficient and cost-effective space missions.
Air-breathing propulsion systems represent a significant departure from traditional rocket technology. Typically, rockets carry both fuel and an oxidizer, which together make up a substantial portion of the rocket's mass. In the case of India's largest rocket, the LVM-3, nearly 86% of its 640-ton lift-off mass is propellant, with the oxidizer alone accounting for 70% of the propellant's weight. However, in an air-breathing system, the rocket carries only the fuel, relying on atmospheric oxygen as the oxidizer. This results in a much lighter rocket, significantly improving efficiency and reducing costs.
ISRO's upcoming test will be conducted using a modified version of the Rohini-560 experimental rocket, named the Advanced Technology Vehicle (ATV). This test follows ISRO's initial experimental flight of air-breathing propulsion technology on August 28, 2016, which successfully demonstrated the ignition of air-breathing engines at supersonic speeds, flame holding, air intake mechanisms, and fuel injection systems. The ATV, weighing 3,277 kg at lift-off during the maiden test, will again serve as the solid rocket booster carrying the scramjet test articles to supersonic speeds.
The scramjet engine, a type of air-breathing propulsion, is at the heart of this test. Scramjets, or Supersonic Combustion Ramjets, operate at hypersonic speeds (Mach 5 and above) and rely on the vehicle's high velocity to compress incoming air. This compressed air is mixed with hydrogen fuel and ignited, producing thrust. Unlike traditional engines, scramjets have no rotating parts and maintain supersonic airflow throughout the combustion process, making them ideal for very high-speed flight.
ISRO's scramjet engine, which uses hydrogen as fuel and atmospheric oxygen as the oxidizer, demonstrated its capabilities during the 2016 test with a hypersonic flight at Mach 6 for a duration of five seconds. The upcoming test aims to build on this success, moving towards an autonomous vehicle powered by a scramjet engine capable of accelerating for 250 seconds.
In addition to scramjets, other types of air-breathing propulsion include ramjets and dual-mode ramjets (DMRJ). Ramjets operate efficiently at speeds between Mach 3 and Mach 5 but cannot start from a standstill and require a rocket to bring them to supersonic speeds. Dual-mode ramjets can transition between ramjet and scramjet modes, making them versatile for a wider range of speeds.
India joins an elite group of countries pursuing air-breathing propulsion technology, which promises significant advancements in aerospace capabilities. These technologies are not only crucial for reducing the costs of space missions but also have strategic implications for developing advanced, high-speed aerospace vehicles.
As ISRO prepares for this critical test, the successful demonstration of air-breathing hypersonic technology will pave the way for future innovations and strengthen India's position in the global space race.
