Cryogenic Transfer Stage for Beyond Low Earth Orbit Access

The proposed innovation is a transfer stage spacecraft, Bifrst, a high thrust vehicle for rapid orbital transfer both as an upper stage on commercial launch vehicles and reusable orbital maneuvering vehicle, enabling both NASA and commercial missions. Rapid access to most of these orbits today is nonexistent especially for small spacecraft. A longer term application of the technology is a scaled-up Mjlnir engine for expendable and reusable launch vehicles to improve performance, reliability, and safety with much lower green-house gas (GHG) emissions. The proposed innovation is a transfer stage spacecraft, Bifröst, a high thrust vehicle for rapid orbital transfer both as an upper stage on commercial launch vehicles and reusable orbital maneuvering vehicle, enabling both NASA and commercial missions. A secondary capability supports the emerging military need for space access and domain awareness of critical military orbits throughout cislunar space. Rapid access to most of these orbits today is nonexistent. A longer term application of the technology is a scaled-up Mjölnir engine for expendable and reusable launch vehicles to improve performance, reliability, and safety with much lower green-house gas (GHG) emissions. The objectives of this Phase 2 proposal are focused on maturing the fluid and propulsion system technology readiness level (TRL) of the Bifröst spacecraft. Demonstrate key operability of the Mjölnir engine under-hot fire conditions with the propulsion breadboard Develop bi-propellant reaction control system (RCS) thruster which meets Bifröst requirement Demonstrate operation of RCS thruster operation while integrated with propulsion breadboard Demonstrate Bifröst propulsion system operation with autogenous pressurization under engine hot-fire conditions using breadboard Validate mass property targets for key Bifröst propulsion component Develop CONOPS for launch with one or more venture-class launch vehicle Complete concept design of flight-like fill/drain/vent Establish relationships with potential payload missions Refine vehicle performance specifications based on maturation of subsystem and component designs Phase II Deliverables Test and data summary for hot-fire testing of Mjölnir engine demonstrating engine operability and performance Test and data summary for demonstration of autogenous pressurization Test and data summary for RCS development Updated mass properties accounting
Benefits: Bifröst is a transfer stage spacecraft powered by the Mjölnir engine and optimized for small spacecraft and venture class launch vehicles. From low earth orbit a 3,000 lb gross Bifröst can deploy a 400 lb payload to geostationary earth orbit, >200 lbs to any location in cislunar space, and >110 lbs to Venus and Mars transfer as well as earth escape velocity. Bifröst avionics support deep space applications with communications and payload support. Scaling the tankage to 20,000 lb gross, the same Mjölnir engine inserts over 10X greater payloads. There is strong interest in a 3,000 lb OTS enabling militarily responsive space domain awareness for all orbits and also offering an exciting path to expanded commercial activities beyond low earth orbit. The Mjölnir engine and Bifröst spacecraft will be available for orbit transfer, lunar lander, or related capabilities.