Abstract: Helium inflatable emergency locator balloon having a longitudinal body and side wings defining horizontally a triangular, bilaterally symmetrical tetralobate monochamber having a forward lobate nose, a rearward lobate hind section and flanking rearward lobate wings, the latter three lobate portions being in side by side spaced apart and unconnected relation to each other and the hind section end extending rearwardly slightly beyond the wind ends, and in inflated condition each of the body and wings defining in longitudinal cross section a bilaterally symmetrical convex profile having a slightly rounded upper side and underside, a small rounded leading edge and an acutely pointed trailing edge, and a respective tail of streamer strips attached to each of the hind section and wing ends, such strips preferably constituting tuned radar reflective dipole strips, and optionally alternatively similar dipole strips being individually loosely disposed within the balloon, and a gas supply device for inflating the ballo