Described herein are features for high altitude lighter-than-air (LTA) balloon antenna systems and associated methods. One or more long wire communications antennas may be built into the balloon skin. The antenna may extend under, in, on or otherwise along one of the seams formed by connected edges of gores that define the balloon volume. The antenna may include an elongated electrical conductor with a length based on a desired communication frequency. The antenna may be secured with load tape along the seam. The antenna may be included in an LTA balloon system that includes multiple balloons connected in tandem, such as a zero-pressure balloon (ZPB) and one or more variable air ballast super-pressure balloons (SPB).