A mechanically steered, horizontally polarized, directional antennae for aerial vehicles, such as UAVs. The antenna system can include a planar substrate with a horizontally polarized antenna embedded therein. A rotation member, on one end, can be attached to the planar substrate, and can extend from an external surface of the aerial vehicle. An actuator can be coupled to the rotation member to rotate the rotation member. A communication controller of the aerial vehicle can control the actuator to beam horizontally polarized radiofrequency (RF) waves to a target receiver or receive a wave front from a target transmitter.