Described herein are unmanned aerial vehicles (UAVs) and systems and methods for dynamically selecting directional antennas onboard the UAV for wireless transmissions. For example, an embodiment pertains to a UAV that comprises a flight control system in remote communication with a remote receiver via directional antennas onboard the UAV. The flight control system is operatively coupled with a propulsion system to control the flight of the UAV. While in-flight, the flight control system is configured to determine an orientation and position of the UAV. It is further configured to select a subset of directional antennas to transmit from based on the determined orientation and position, among other factors. The flight control system then directs a transmitter to send wireless communications using the selected directional antennas.