CNET News: The Excalibur, a new turbine-electric hybrid propelled VTOL (vertical takeoff and landing) unmanned attack drone, has successfully completed another test flight after taking on two new onboard computers last week.Developed by Aurora Flight Sciences Corp. for the US Army Aviation Applied Technology Directorate and the Office of Naval Research, the Excalibur is another radical robo-craft concept vying to fill the military’s burgeoning demand for specialized unmanned aerial vehicles.