AbstractWe present the design and implementation of a small autonomous unmanned aerial vehicle capable of high‐speed flight through complex natural environments. Using only onboard GPS‐denied sensing and computation, we perform obstacle detection, planning, and feedback control in real time. We present a novel integrated approach to perception and control using pushbroom stereo, which exploits forward motion to enable efficient obstacle detection and avoidance using lightweight processors on an unmanned aerial vehicle. Our use of model‐based planning and control techniques allows us to track precise trajectories that avoid obstacles identified by the vision system. We demonstrate a complete working system detecting obstacles at 120 Hz and avoiding trees at up to 14 m/s (31 MPH). To the best of our knowledge, this is the fastest lightweight aerial vehicle to perform collision avoidance using three‐dimensional geometric information.