An interesting radiating form, the eggbeater antenna produces circular polarization at high angles, yet linear polarization at the horizon. Unlike soundwaves, radiowaves have a distinct polarization, with a magnetic field exactly perpendicular to an electric field. This perfect orthogonal relationship is a key feature of the electromagnetic domain, with time being a third orthogonal axis.
Soundwaves have two axes, not three. But soundwaves, being mechanical, and in a springy medium such as air, have other interesting properties that aren't obvious.
The eggbeater is useful for communications with overhead aircraft and satellites.