The US Navy has begun its first unmanned air-to-air refuelling trials, only weeks after the first unmanned aircraft carrier landings.
For the refuelling trials, software from the Northrop Grumman X-47B was uploaded to a manned surrogate aircraft, a contractor-flown Learjet 25B, refueling from a Boeing 707. Though a pilot was on board the Learjet, the aircraft flew autonomously.
Surrogates are often used as stand-ins for unmanned aircraft, especially on the X-47B programme, which has used both the Learjet and a surrogate Boeing F/A-18.
"By demonstrating that we can add an automated aerial refuelling capability to unmanned or optionally-manned aircraft, we can significantly increase their range, persistence and flexibility," says Capt Jaime Engdahl, the Navy's programme manager. "This is a game-changer for unmanned carrier aviation."
Testing began on 28 August, flying out of Niagara Falls, New York.