DRDO achieves milestone on scramjet engines needed for hypersonic missiles

New Delhi: India’s quest for next generation hypersonic missiles received a boost on Tuesday with the Defence Research and Development Organisation reporting first successful testing of an indigenous scramjet engine that will be at the core of such weapons when they are realised.

Defence Research and Development Laboratory, a Hyderabad-based DRDO laboratory that was developing the engine, carried out the ground test for 120 seconds for the first time in India, a defence ministry official said.

“The achievement marks a crucial milestone in the development of next-generation hypersonic missions,” Defence Minister Rajnath Singh said, complimenting the DRDO.

Scramjet engines are advanced jet engines that allow supersonic combustion. They are needed for hypersonic missiles that travel at speeds greater than Mach 5, which means five times the speed of sound or more than 5,400 km/hr.

Since such advanced weapons can bypass the existing air defence systems for delivering rapid and high-impact strikes, several nations including USA, Russia, India and China are actively pursuing the hypersonic technology.

The key to hypersonic vehicles is scramjets that are air-breathing engines capable of sustaining combustion at supersonic speeds without using any moving parts.

“The ground test showcased several notable achievements, demonstrating its potential for operational use in hypersonic vehicles, like successful ignition and stable combustion,” the official said.

Ignition in a scramjet engine is like "keeping a candle lit in a hurricane". This was achieved by incorporating an innovative flame stabilisation technique that holds continuous flame inside the combustor with an air speed in excess of 1.5 km per second.

The defence scientists perfected the technology after years of diligent research on many novel and promising ignition and flame holding techniques.

Another breakthrough was joint development of the scramjet fuel, the first time in India, jointly by DRDL and industry. The fuel offers dual benefits of significant cooling improvement and ease of ignition.

The team developed a special manufacturing process to achieve stringent fuel requirements of DRDL at industrial scale.

Moreover, a special thermal barrier coating, designed to withstand extreme temperatures encountered during hypersonic flight, was also developed as a part of the programme. This was done in partnership with the Department of Science and Technology.

The coating – having high thermal resistance and capable of operating beyond the melting point of steel – was applied inside the scramjet engine using special deposition methods that enhance their performance and longevity.

The ground testing comes within months of DRDO carrying out a successful flight-trial of India’s first long-range hypersonic missile off the Odisha coast. The missile with a range of 1,500 km was flight-tested in November.

The Indian Space Research Organisation is also working on having its own scramjet engines for developing the next generation launch vehicles.