NASA’s new type of rocket engine, the Rotary Detonation Rocket Engine (RDRE), once considered impossible, could revolutionize space exploration. NASA engineers at the Marshall Space Flight Center in Huntsville, in partnership with IN Space LLC, have made a significant advancement in rocket engine technology that could transform the way we explore deep space, according to NASA. The RDRE has been developed and tested, and has the potential to completely change the experience of spaceflight.
The Rotary Detonation Rocket Engine operates differently from conventional engines, as it relies on explosive detonations rather than combustion. This concept, which dates back to the 1950s at the University of Michigan, was first tested in space by Japan in 2021. In the engine, fuel is detonated in a circular chamber, producing a shockwave that propels the spacecraft and triggers subsequent detonations in a continuous cycle until the fuel is depleted.
The main advantage of the Rotary Detonation Rocket Engine is its high fuel efficiency, estimated to result in a 25% reduction in fuel consumption compared to traditional engines. However, controlling the explosive detonations is challenging, making it a more complex process than combustion. Unlike pulse detonation engines (PDE), which require cleaning the combustion chamber before each explosion, the RDRE operates continuously in a self-sustaining manner without interruptions.
NASA’s statement accordingly mentions that RDRE generates more energy while using less fuel than current propulsion systems, and therefore may be able to deliver humans to distant destinations such as the Moon and Mars. All this sounds good, and we may be relatively close to practical application. During the tests, RDRE achieved its primary goal by demonstrating that its parts, made from novel 3D printing designs and processes, can withstand the extreme heat and pressure generated by detonations.
When operating at full throttle, the RDRE produced more than 4,000 pounds (1,814 kg) of thrust for nearly one minute at an average chamber pressure of 622 pounds per square inch (63.5 bar). This is the highest pressure value ever achieved with this design and is a testament to the engine’s incredible performance.
The RDRE incorporates a NASA-developed GRCop-42 copper alloy, which, combined with a special manufacturing process, allows the engine to operate in extreme conditions for extended periods without overheating. In other words, the RDRE currently holds a lot of promise, and could help both NASA and commercial spaceflight deliver more payloads to deep space over time.