So, the Navy just took a big step toward achieving the military’s goal of having UAV’s capable of mid-air refueling.

Last month, a Navy Learjet equipped with flight control software and refueling hardware from the service’s X-47B Unmanned Combat Air System Demonstrator jet autonomously completed a mock air-to-air refueling from a Boeing 707-based tanker (shown in the picture above, note the safety pilot you can see in the Learjet’s cockpit).

Remember, the Northrop Grumman-made X-47B is designed to prove that a stealthy, fighter-size drone can be operated from aircraft carriers and perform long-range strike, ISR and aerial refueling missions. X-47B is meant to pave the way for the Navy’s Unmanned Carrier-Launched Airborne Surveillance and Strike (UCLASS) combat drone, set to enter service later this decade.

The technology used in the refueling tests is similar to this tech that will be used to allow the X-47B to take-off and land aboard aircraft carriers.

From a NAVAIR press release:

“The AAR segment of the program is intended to demonstrate a system that will enable the X-47B UCAS-D to safely approach and maneuver around tanker aircraft, performing both Navy and Air Force style refueling techniques,” said Capt. Jaime Engdahl, Navy UCAS program manager. The Navy has been working closely with the Air Force Research Lab for the past decade to develop technologies and operating concepts for AAR, Engdahl said. Both services share a common goal of enabling tankers to autonomously refuel manned and unmanned aircraft in the future, he added. The UCAS-D team began this test phase in November when a team from Northrop Grumman installed X-47B hardware and software on a Calspan Learjet surrogate aircraft. The initial ground and taxi tests culminated in the first AAR test flight Dec. 20. The team then conducted a series of flights using the surrogate aircraft, equipped with X-47B software and hardware, and an Omega K-707 Tanker. The Learjet successfully completed multiple air-refueling test points autonomously while commanded by a ground operator. The AAR segment of the UCAS-D program is designed to assess the initial functionality of the X-47B AAR systems and navigation performance, as well as to test the government tanker refueling interface systems. The AAR program is using similar command and control, and navigation processes being demonstrated by the UCAS team aboard the aircraft carrier.

This is a major step in advancing the flight control systems that allow UAVs to safely fly extremely close to other aircraft and execute potentially dangerous missions. Keep in mind that so-called, automatic sense-and-avoid technology is the key to allowing drones to safely fly in crowded airspace to keep things like this from happening. Once sense and avoid is perfected, you’ll see UAVs regularly flying aerial refueling missions and others that require serious interaction with other aircraft, manned and unmanned. You might even see them cleared by the FAA to fly in civil airspace.