Identified flying object.

Flying doughnut? UFO? Getting closer. It's Cypher, a "spying saucer" designed by engineers at Sikorsky Aircraft in Stratford, Conn.

The U.S. military plans to use this 2-meter (6-foot) wide flier to conduct surveillance--surveying a battlefield from the air, for example. But the spying saucer can land on rooftops or peer into windows of tall buildings, too.

What gets Cypher off the ground? Lift, the force that allows any aircraft to overcome gravity and climb into the air.

Cypher gets its lift from two rotors (thin fanlike blades) stacked in its "doughnut hole." Each blade is curved on top and flat on the bottom. As the blades spin, air flows faster over the curved upper surfaces, lowering air pressure above the blades. Because air is pushing more strongly against the bottom of the blades (from an area of high pressure to low), the craft lifts off. The spinning rotors also compress the air beneath the aircraft, helping it to rise.

Cypher's shape offers several advantages over a helicopter, which also uses rotors to fly. First, Cypher's rotors are protected by the doughnut's outer rim. The spying saucer can bump into trees, buildings, and other objects without damaging its rotors. And the remote-controlled vehicle is pilotless, so it can fly into military zones without risking lives.

Cypher's designers are now testing all its capabilities before it takes to the skies to fly and spy.