DARPA awards contracts for orbital nuclear propulsion demonstrator
DARPA's nuclear space rocket project is progressing, with contracts awarded to General Atomics, Blue Origin, and Lockheed Martin for the first phase of the agency's Demonstration Rocket for Agile Cislunar Operations (DRACO) program. The goal is to place a Nuclear Thermal Propulsion (NTP) demonstrator into low Earth orbit by 2025.
Humanity is just dipping its toes into the solar system, but it's surprising to many to find out that we are already near the theoretical limits of what chemical rockets can do. In fact, that limit emerged almost as soon as Werner Von Braun produced the first practical rockets in the 1940s.
That's a real problem, not only because, with chemical rockets, a crewed mission to Mars is about at the absolute limits of the technology, but they also have trouble fulfilling requirements for space missions closer to home.
For example, the US Department of Defense (DoD) has a core requirement for rapid maneuvering not only on land, sea, and air, but also in space. Currently, maneuvering in space relies on either chemical rockets that provide high thrust and low propellant efficiency, and electric propulsion with its high efficiency and low thrust. This is a problem in cislunar space, where shifting orbits quickly need both high thrust and high efficiency.
This is where NTP systems come in. By replacing a chemical rocket's combustion chamber with a nuclear reactor to heat a propellant, like hydrogen, to extreme temperatures, it's theoretically possible to reach thrusts 10,000 times that of an electric engine and up to five times the efficiency of a chemical rocket.
So far, DARPA has already contracted Gryphon Technologies to work on a High-Assay Low Enriched Uranium (HALEU) NTP system. Now, the DRACO program is aiming to produce an orbital demonstrator that will entail an 18-month Phase 1 involving two parallel tracks.
For Track A, General Atomics will work on the preliminary design of an NTP reactor and propulsion subsystem concept. Meanwhile, Track B will see Blue Origin and Lockheed Martin independently developing an Operational System (OS) spacecraft concept based on the mission objectives, and the design of a Demonstration System (DS) spacecraft concept. These will lead to the next phases that will focus on detailed design and fabrication of the spacecraft for the orbital demonstration.
"The performer teams have demonstrated capabilities to develop and deploy advanced reactor, propulsion, and spacecraft systems," says Maj Nathan Greiner, USAF, program manager for DRACO. "The NTP technology we seek to develop and demonstrate under the DRACO program aims to be foundational to future operations in space. This first phase of the DRACO program is a risk reduction effort that will enable us to sprint toward an on-orbit demonstration in later phases."