California-based aerospace company AeroVironment has developed some fascinating Unmanned Aircraft Systems (UAS) over the years, including the High Altitude Long Endurance Global Observer, a hummingbird-like nano air vehicle, and the hand-launched Wasp III reconnaissance platform. In 2008, the Defense Advanced Research Projects Agency (DARPA) awarded the company US$4.6 million in funding to develop a "perch-and-stare" aircraft, for use in military surveillance. Today, AeroVironment unveiled the result - the Shrike Vertical Take-off And Landing (VTOL) UAS.

The Shrike is a quadrocopter equipped with a high-resolution video camera, that can transmit real-time encrypted footage to remote human operators. It can hover in place very quietly for up to 40 minutes, but also has the ability to land (or "perch") in discrete locations, from where it can transmit for several hours. When it's done, it can simply take off vertically, and fly back to its base.

The UAS weighs about five pounds (2.27 kg), and is small enough to be carried in a backpack. It is remotely operated through AeroVironment's Ground Control System, which is already used by the company's other aircraft.