The huge Global Observer, tested last week at Edwards Air Force Base in California, can fly for days at 65,000 feet, out of range of most anti-aircraft missiles, the Times said. It can rival spy satellites by surveying 280,000 square miles -- an area larger than Afghanistan -- in one glance.
Two other drones that will be tested soon are the bat-winged X-47B, which can carry laser-guided bombs and be launched from an aircraft carrier, and the Phantom Ray, which can slip behind enemy lines to take out radar installations.
Unlike most of the current Predator and Reaper drones, the new planes have jet engines and can evade radar.
Current spy planes can stay airborne for only about 30 hours. The Global Observer is designed to exceed that several times over, flying up to a week at a time. It is designed to do the work of satellites, including relaying communications between military units and detecting missiles as they are launched.