Phase-Locked Traveling Bubble Propulsion: A Conceptual Framework for Wave-Coupled Spacecraft Transport This preprint presents an original spacecraft propulsion concept authored by Nansi Readman. The idea explores whether a spacecraft hull could synchronize (phase-lock) with a traveling field structure — forming a coherent “rideable pocket” or bubble — and achieve motion by remaining stationary inside that pocket while the surrounding field pattern propagates. Instead of relying solely on reaction mass, the concept reframes propulsion as a synchronization problem: the hull, plasma sheath, and traveling pulse structure act together as a coupled system. In theory, this could allow the vehicle to “ride” a controlled wave or traveling disturbance while occupants remain inside a relatively calm interior pocket. The paper develops the conceptual model, motivation, qualitative physics, hull architecture ideas, partial light-lensing implications, and a staged research path — including a tabletop experiment where a small object locks onto and rides a traveling wave in a circular membrane or liquid surface. The work does not claim demonstrated feasibility; it is presented as a hypothesis-driven conceptual framework intended for technical evaluation and discussion. Authorship & Attribution This concept and terminology — including the phase-locked traveling bubble propulsion model and wave-coupled hull structure — are original to Nansi Readman. Publication on Zenodo establishes authorship and priority of disclosure. Any discussion or further study of this framework should acknowledge the author. No funding is requested. This work is shared for open scientific exploration.