Produced by: Tarun Mishra
Representative Picture
The Indian Space Research Organisation (ISRO) plans to test-fly an air-breathing propulsion system on July 22 at 7:30 am IST from Satish Dhawan Space Centre in Sriharikota, reported WION.
The test will use a modified version of ISRO’s 'Rohini-560' experimental rocket, called the Advanced Technology Vehicle (ATV). This vehicle will carry the test articles for the air-breathing propulsion system.
This test follows ISRO’s first experimental flight of air-breathing propulsion technology on August 28, 2016. The aim is to advance the technology further.
Unlike conventional rockets that carry both fuel and an oxidiser, air-breathing propulsion systems use atmospheric oxygen to burn the fuel, making the rocket lighter and more efficient. This technology is suitable for use within the Earth's atmosphere up to 70 kilometers in altitude.
The absence of an on-board oxidiser in the atmospheric phase significantly reduces the rocket's weight. For example, ISRO’s largest rocket, LVM3, carries 555 tonnes of propellant, of which 385 tonnes is oxidiser. Air-breathing systems could reduce this weight and increase efficiency.
The three main types of air-breathing engines are Ramjet, Scramjet, and Dual Mode Ramjet (DMRJ). Ramjets operate at supersonic speeds, Scramjets at hypersonic speeds, and DMRJs can transition between subsonic and supersonic combustion modes.
ISRO has developed a Scramjet engine that uses hydrogen as fuel and atmospheric oxygen as the oxidiser. In 2016, ISRO conducted a successful short-duration test of its Scramjet engine, achieving hypersonic flight at Mach 6 for 5 seconds.
The 2016 test demonstrated critical technologies such as supersonic ignition, flame holding, air intake mechanism, and fuel injection systems. ISRO plans to develop autonomous vehicles powered by Scramjet engines and aims to build a Hypersonic Air Breathing Vehicle with Air Integration Systems (HAVA).
Developing air-breathing propulsion technology is crucial for advancing high-speed aerospace vehicles. With this test, India joins a select group of countries demonstrating flight testing of Scramjet engines.