Boeing's A160T Hummingbird unmanned rotorcraft has completed an 8h flight, it's longest yet, carrying a 450kg (1,000lb) payload.
The helicopter reached an altitude of 5,000ft (1,500m) on the 26 September flight from Victorville, California. It was carrying a simulated battlefield resupply payload.
"The ability to carry a 1,000lb payload and fly for that duration puts the A160T in a category by itself," says programme manager Jim Martin.
First flown in June, the A160T is a turbine-powered version of the Hummingbird unmanned rotorcraft originally designed by Frontier Systems, which was acquired by Boeing in 2004.
The Hummingbird has an optimum-speed rotor that varies its RPM with altitude, cruise speed and gross weight. Conventional helicopter rotors operate at 100% RPM almost all the time.
Slowing the 11m-diameter rigid rotor by up to 50% extends the unmanned helicopter's endurance. Boeing's goal is to fly the A160T for 18h with a 135kg payload.
Powered by a Pratt & Whitney Canada PW207, the A160T is designed to cruise at more than 140kt (260km/h), hover up to 15,000ft and reach a ceiling of 25,000-30,000ft.
Boeing says future payloads will include a combination of sensors, weapons and systems to perform a range of missions including persistent surveillance, communications relay, target acquisition, direct attack, precision resupply and personnel recovery.
US SOCOM plans to evaluate the A160's military utility. Separately, the special-forces command also plans to evaluate AeroVironment's hydrogen-powered Global Observer UAV, which is designed to stay aloft for up to seven days at altitudes from 55,000-65,000ft.
AeroVironment has received a $57 million contract to deliver one Global Observer, with an option for two more vehicles taking the potential value to $108 million.
The goal of the joint capabilities technology demonstration is to evaluate the tactical utility of a UAV able to operate in the stratosphere for up to seven days.
A system comprising two or three air vehicles would be able to provide continuous surveillance or communications relay over an area of interest, says AeroVironment.