An Indian defence startup is planning to conduct the first flight test of its rotating detonation engine next year. The new engine could help power India's next generation of missiles, according to Deep Propulsion.
Speaking at the NDTV Defence Summit 2026, Deep Propulsion CEO Saurav Jha said the company has already tested a flight-capable version of the engine on the ground. "We are looking at a first flight test next year itself," Jha said.
The company wants to show that the engine can produce positive thrust and accelerate a system to Mach 3 or beyond during the test, he said. Deep Propulsion has already carried out five tests of the engine at the DRDL facility in Hyderabad. The tests were conducted within about 24 hours.
"We did five tests in a course of 24 hours showing repeatability and in some sense functional throttlability as well because the fuel air ratio, the fuel air mix was varied in these tests," he said.
The company also changed the fuel-air mix during the tests to check how the engine responds. A conventional jet engine burns fuel slower than the speed of sound.
A rotating detonation engine uses a much faster form of combustion. The process happens at supersonic speed.
“What you are doing in a rotating detonation engine, which is what we are building, which is a detonation engine, this process is unfolding very rapidly, faster than the speed of sound,” he said.
He said the company's air-breathing rotating detonation engine can have more than three times the thrust-to-weight ratio of a conventional jet engine with a similar thrust level.
Jha said the company is first focusing on high supersonic speeds rather than directly moving into hypersonic systems. "Our stuff can go from anywhere between Mach 1.5 to Mach 4.5," he asserted. Hypersonic speed starts at Mach 5.
"If you want a range boost, this will give you a 30 to 35% range boost with the same kind of airframe," he added.
He said the bigger advantage could come from designing a completely new missile around the smaller engine instead of simply replacing an existing engine. "If you want the real gains from this, you need to build a new system around the technology," Jha stressed.
The company is also building its own testing facilities. Its combustor test facility at the IIT Madras Discovery Campus can handle an air flow of up to 10 kg per second. "Propulsion is the key," Jha said.
