Chennai, Aug 28 (IANS): India on Sunday successfully tested its own scramjet or air breathing engine with the launch of a rocket, said a senior official of Indian Space Research Organisation (ISRO).

"The mission was successful. Two scramjet engines were tested during the flight," the official told IANS.

He said that as scheduled at 6 a.m., the two stage/engine RH-560 sounding rocket took off from the rocket port located at Satish Dhawan Space Centre (SDSC) in Sriharikota in Andhra Pradesh.

He said the two air breathing engines were like hugging the rocket on its sides and normally when the rocket reaches a height of 11 km the scramjet engines would start breathing air.

The scramjet engine, used only during the atmospheric phase of the rocket's flight, will help in bringing down the launch cost by reducing the amount of oxidiser to be carried along with the fuel.

Later, the ISRO in a statement said: "With this flight, critical technologies such as ignition of air breathing engines at supersonic speed, holding the flame at supersonic speed, air intake mechanism and fuel injection systems have been successfully demonstrated."

The scramjet engine designed by ISRO uses hydrogen as fuel and the oxygen from the atmospheric air as the oxidiser.

The test flight was the maiden short duration experimental test of ISRO's scramjet engine with a hypersonic flight at Mach 6.

ISRO's Advanced Technology Vehicle (ATV), which is an advanced sounding rocket, was the solid rocket booster used for testing the air breathing engine.

The rocket weighed 3,277 kg during lift-off.

According to ISRO, some of the technological challenges handled by ISRO during the development of scramjet engine include the design and development of hypersonic engine air intake, the supersonic combustor, development of materials withstanding very high temperatures, computational tools to simulate hypersonic flow, ensuring performance and operability of the engine across a wide range of flight speeds, proper thermal management and ground testing of the engines.

"India is the fourth country to demonstrate the flight testing of scramjet engine. The successful technology demonstration of air-breathing scramjet engines in flight by ISRO is a modest yet important milestone in its endeavour to design and develop advanced air breathing engines including engines for ISRO's future space transportation system," the space agency added.