The Phantom Sentinel was an American unmanned aerial vehicle developed by VeraTech Aero. Utilising a "boomerang" design, the Phantom Sentinel was designed to be nearly invisible. Driven by electric-engine propellers, the rapid rotation of its entire body during flight meant that persistence of vision would render it translucent in the same way as fan blades.[1] First flying in 2006, the Phantom Sentinel was designed for hand launch and was equipped with a high-speed camera providing 360-degree video coverage.[2] It was electrically powered and designed to have an endurance of 40 minutes.[1]