Flight Works is proposing to continue the development and demonstration of a low cost, compact, high performance lunar transfer stage designed for small launchers like Rocket Lab’s Electron and Virgin Orbit’s Launcher One. With a total wet mass around 200 kg without payload, the transfer stage is designed to provide high-thrust, high delta-V capabilities of over 3 km/s to one or more nanosat payloads weighing more than 30 kg. It will propel small spacecraft (CubeSat or nanosat) from Low Earth Orbit on to Trans-Lunar Injection trajectories and into lunar orbit. The system features a full set of avionics and can support payloads up to 40 W continuous (90 W peak). It can either stay attached to the small primary payload for long term mission operations, or deploy the latter at its destined lunar orbit.
Other benefits include scalability; use of green propellants and low-pressure tanks minimizing range safety operations and costs; high thrust for rapid, efficient transfer (compared with electric propulsion systems which have to be launched at higher orbits to avoid low altitude drag and which can require months to reach the targeted orbit while exposing the system to the damaging radiation of the Van Allen belts); minimized size provided by a high performance propulsion system; and attitude control system which can ride along for cislunar operations.
A stage providing over 3 km/s delta-V to a nanosat payload can be an enabler for many NASA lunar and interplanetary missions. These include missions similar to the NASA Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE), or follow-ons to NASA’s Mars CubeSat missions MarCO-A and -B, and unlike MarCO, could enable Mars Orbit Insertion. It can also be used for NASA LEO and GEO nanosat missions, whether launched as dedicated or as secondary payloads.
Non-NASA applications include commercial and DoD missions requiring high orbital maneuver capabilities. These include dedicated missions on small launch vehicles where additional delta-V is required, as well as commercial space-tug applications, e.g. on Falcon-9 rideshare launches. The stage can also be used for other applications such as orbital inspectors from LEO to cislunar operations.