Embodiments for determining the bearings to targets from a remote location are disclosed. The apparatus consists of an array of acoustic sensors that is capable of autonomous flight. The array may be large in diameter, approximately one meter or greater. The apparatus is capable of navigating its flight to arrive at a predetermined location, measuring acoustic sound waves emitted by targets both during flight and after landing. The apparatus may then calculate the bearings to the targets and transmit this information to a remote location.