In a first global call, the Japan Aerospace Exploration Agency (JAXA) announced on August 19 that it had successfully demonstrated the operation of a “rotary detonation engine” in space, with the aim of to extend the method of propulsion to deep space travel in the future.
The “impossible” motor uses rotating explosions within a ring channel. This method generates a lot of super efficient thrust from a considerably smaller engine that consumes less fuel and has the potential to change the game.
Space-tested rotary detonation motor
The revolutionary system was mounted on the S-520-31, a single-stage rocket capable of lifting a payload of 100 pounds (220 pounds) well above 300 km and launched from Uchinoura space center on July 27. The show was a resounding success.
The rocket began testing after the first stage separated, firing the rotary detonation engine for six seconds. When the rocket recovered from the ocean after the demonstration, the rotary detonation engine was found to produce about 500 Newtons of thrust.
To put it in context, the SpaceX’s large Falcon Heavy payload rocket, for example, has three cores of nine Falcon 9 engines whose 27-Merlin engines generate more than 5 million pounds of thrust on takeoff. This equates to approximately eighteen 747 aircraft. Thus, while it is fair to say that the rotary detonation engine is in its early stages, JAXA engineers believe that the success of the test in space shows that these engines can allow us superior interplanetary navigation with less fuel and weight, which will be crucial as humanity considers new homes around the cosmos.
Japan expects to put the technology into practical use within five years, according to a statement last month by Jiro Kasahara, a professor at Nagoya University who collaborates with JAXA on the technology, according to the Japan Times.
In general, rotary detonation engines have the potential to reduce the weight of rocket payloads, reduce launch costs and propel us to the stars, which is why Japan is not the only country trying to design the bear. In 2020, a team of researchers announced that it had successfully built and tested an experimental model of a rotary detonation engine in collaboration with the United States Air Force.
The engine design was reportedly being evaluated as a possible replacement for the Aerojet Rocketdyne RL-10 rocket, and investigators said the U.S. Air Force is heading for a launch test of rockets in 2025.