If you wander out into a gaggle of fellow humans in total darkness, chances are you're going to bump into one or two. Such is not the case for bats, which do much of their hunting after the sun sets. Boston University's Intelligent Mechatronics Lab launched operation Batcopter to better understand how bats can fly in clusters large enough to be detected by radar without colliding. Equipped with a GoPro 3D HD camera, GPS, and OpenPilot's CopterControl system, the 1.8-pound quadcopter UAV joined Brazilian free-tailed bats in the skies of South Texas, capturing some pretty cool footage along the way. A trio of high-speed infrared cameras positioned on the ground photographed the aircraft's interactions with the flying mammals, which seemed to maneuver around the man-made intruder without incident, until a rotor failure resulted in a Batcopter inversion and subsequent ground collision. Even so, the craft still managed to take to the skies. Jump past the break to see the crippled UAV in action, and hit up the source link for some awesome infrared footage and stills.