Like its diminutive avian namesake, Boeing's A160T Hummingbird is a whiz at hovering. And it turns out the prototype aircraft can also hoist a hefty load.
The unmanned helicopter this week flew for eight hours--its longest flight to date--and as high as 5,000 feet while burdened with a 1,000-pound payload. The test flight goes a long way toward proving the Hummingbird fit for use in military operations, where it could ferry supplies, sensors or weapons to the battlefield, perform surveillance and target acquisition, or even rescue pilots who've been shot down.
Over time, Boeing wants to see the 35-foot Hummingbird fly longer, but with a lower weight: 18 consecutive hours with a 300-pound payload.
The A160T Hummingbird flew for the first time in June, and has flown several times since then. It's a turbine-powered version of the earlier piston-powered A160, which dates back to 2002, and the second of a planned 11 A160Ts that Boeing is building for DARPA.
Eventually, Boeing sees the Hummingbird flying for up to 20 hours at speeds above 140 knots and at altitudes reaching 25,000 to 30,000 feet (but hovering below 15,000 feet). A notable element in the design of this unmanned aerial vehicle is the variable speed of its 36-foot rotor; the UAV operator can adjust the rotors' RPMs at different altitudes and cruise speeds to improve flight efficiency.