Abstract: Launch vehicles with ring-shaped external elements, and associated systems and methods are disclosed. An aerospace system in accordance with a particular embodiment includes a launch vehicle having a first end and a second end generally opposite the first end, with the launch vehicle being elongated along a vehicle axis extending between the first and second ends, and having an external, outwardly facing surface. The system can further include an annular element carried by the launch vehicle, the annular element having an external, inwardly-facing surface radially spaced apart from, and extending at least partially circumferentially around, the vehicle axis. The annular element can have a first edge surface facing a first direction along the vehicle axis, and a second edge surface facing a second direction along the vehicle axis, the second direction being opposite the first direction.