Falcon X was a proposed spaceflight launch system that uses rockets designed and manufactured by SpaceX. Like the Falcon 1 and Falcon 9 the first stage of this two-stage-to-orbit vehicle would have used liquid oxygen (LOX) and rocket-grade kerosene (RP-1) propellants and was intended to be reusable.[3] The second stage would use liquid oxygen (LOX) and liquid hydrogen (LH2) and be powered by the Raptor engine.
Multiple variants were planned with payloads to low Earth orbit of up to 38000 kg for the basic version and up to 125000 kg for the 3 core heavy, placing the Falcon X design in the heavy-lift to super heavy-lift range of launch systems.[4]
Design
The proposed base Falcon X would have been a two stage,