The nuclear propulsion pour les rockets returns to the front of the stage! For the needs of future missions, in particular to Mars, NASA and DARPA are teaming up to develop and test a next-generation rocket engine, which will use a small fission reactor. Demonstration planned by around 2027.
It’s a safe bet that many associations will step up.
I’m going to talk to my dad about it!
The project is called DRACO, for “Demonstration Rocket for Agile Cislunar Operations”, a very pompous name which strangely hides the very nature of the rocket engine under study between NASA and DARPA, the research agency of the American defence. Because it is a question here of developing a nuclear rocket engine, whose principle, known, is called NTP (Nuclear Thermal Propulsion). Technically, a small fission reactor is used to heat a propellant to a very high temperature, generating a maximum of energy then recovered in thrust by ejecting the gases through a nozzle, as in a conventional rocket engine. A method which is not so complex on paper, and which could provide both power and efficiency (up to three times better than a “classic” rocket engine!). However, an NTP requires very precise studies, because the architecture is different from a conventional engine… And above all, it requires access to small nuclear fission reactors for which even the big names in the industry have to go through state authorities. With DRACO, the two American agencies want to lift this lock and develop both an engine and a demonstrator.
Head to orbit
With DRACO, it’s not just about showing the capabilities of this breakthrough technology during ground tests, even if they will be necessary. DARPA will lead the development efforts, the security aspect and the management of industrial partners, while NASA will offer access to its infrastructures, but also to its teams which will prepare a first demonstration flight, for the moment. scheduled for 2027… We know, however, that this kind of new technology can quickly take a few years to get behind, especially around nuclear power. DRACO will take off for low orbit, and will only operate between an altitude of about 700 and 2000 km: there is no question of risking its descent and its disintegration through the atmosphere. The NTP propulsion itself does not generate radioactive gases or ejections, but it will obviously be necessary to prepare the engine for potential collisions of micrometeorites or space debris, a risk of failed take-off, etc.
Opposition will be heard
If it is technologically attractive, in particular with a view to future journeys to the distance and for the human adventure to Mars (objective already announced for DRACO), the nuclear fission rocket engine must also rely on a strong political support. Indeed, the associated risks will not fail to make anti-nuclear associations react, but also other nations which are not necessarily in phase with the United States and which will not fail to see this development with a negative eye. The management of the end of mission will be scrutinized in particular… But it is not yet on the agenda. Until then, NASA and DARPA will above all move forward together to move from theory to practice, with the help of American industrialists. Last year DARPA had selected Blue Origin, General Atomics and Lockheed Martin for preliminary designs, and NASA had parallel studies with BWX Technologies, General Atomics and USNT (Ultra Safe Nuclear Technologies). The lines are moving: the American agency is also continuing its efforts in other technologies, such as the promising detonation engines, which have recently shown progress.
Source: https://www.nasa.gov/press-release/nasa-darpa-will-test-nuclear-engine-for-future-mars-missions
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