A sounding rocket demonstrating air-breathing propulsion technology was flight tested March 3 by the Indian Space Research Organisation (ISRO). The flight took place from the SatishDhawan Space Centre on the east coast of southern India.

Weighing 3 tons at liftoff, the Advanced Technology Vehicle (ATV) is the heaviest sounding rocket ever developed by ISRO, according to an ISRO press release. The sounding rocket carried a passive scramjet engine combustor module that served as a test bed for air-breathing propulsion technology.

ISRO said the ATV achieved seven seconds of flight Mach 6, proving that it is capable of providing the necessary conditions for a stable ignition of the active scramjet engine combustor ISRO plans to test on the vehicle’s next flight.

Scramjet engines use oxygen from the air to burn — or oxidize — their propellant, potentially eliminating the need for scramjet-equipped launch vehicles to carry big, heavy tanks of liquid oxygen.