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c0lo [soylentnews.org] writes:

Japan successfully tests rocket engine propelled by new technology [japantimes.co.jp]

Japan on Tuesday successfully tested a rocket engine that was propelled by new technology using shock waves produced by burning a mixture of methane and oxygen gases, with the aim of applying the propulsion method to deep space exploration in the future, the country’s space agency said.

The No. 31 vehicle of the S-520 sounding rocket series, measuring 8 meters in length and 52 centimeters in diameter and carrying the engine, lifted off from the Uchinoura Space Center in Kagoshima Prefecture at around 5:30 a.m., according to the Japan Aerospace Exploration Agency.

It reached an altitude of 235 kilometers four minutes and four seconds after the launch and landed in the sea southeast of Uchinoura about eight minutes later, with JAXA retrieving a capsule containing test data in nearby waters.
...
Jiro Kasahara, a Nagoya University professor, jointly developing the technology with JAXA, said the test demonstrated that the engine maintained a propelling force in space as expected.

“We will aim to put the technology into practical use in about five years,” he said.

InterestingEngineering offers some numbers [interestingengineering.com]

The rocket began the tests after the first stage separated, firing the rotating detonation engine for six seconds. When the rocket was recovered from the ocean after the demonstration, it was discovered that the rotating detonation engine produced around 500 Newtons of thrust.

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More info:

Rotating detonation engine [wikipedia.org]

A rotating detonation engine (RDE) is a proposed engine using a form of pressure gain combustion, where one or more detonations continuously travel around an annular channel. Computational simulations and experimental results have shown that the RDE has potential in transport and other applications.

In detonative combustion, the results expand at supersonic speed. It is theoretically more efficient than conventional deflagrative combustion by as much as 25%. Such an efficiency gain would provide major fuel savings.

Disadvantages include instability and noise.

May 2020, UCF Researchers Develop Groundbreaking New Rocket-Propulsion System [ucf.edu]

A University of Central Florida researcher and his team have developed an advanced new rocket-propulsion system once thought to be impossible.
The system, known as a rotating detonation rocket engine, will allow upper stage rockets for space missions to become lighter, travel farther, and burn more cleanly.
The results were published this month in the journal Combustion and Flame. [sciencedirect.com]
“The study presents, for the first time, experimental evidence of a safe and functioning hydrogen and oxygen propellant detonation in a rotating detonation rocket engine,”...

Feb 2021, Successful engine test brings Australian space launch capability a step closer [rmit.edu.au] (also covered by S/N [soylentnews.org]). Not too much information of fuel/oxidant, thrust or frequency of operations for this one.

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