USAF considering 'very large' autonomous airborne tankers to replace KC-135, KC-46 — and Boeing's MQ-25 Stingray UAV is only the beginning

The United States Air Force is investigating the possibility of unmanned aircraft to replace its aging refueling fleet, which includes the KC-135 and KC-46. The MQ-25, developed by Boeing, is seen as the starting point for these efforts. However, range limitations pose a significant challenge to creating an unmanned tanker. The MQ-25 can only fly about 500 miles and transport roughly 7.5 tons of fuel, far less than the KC-46's 7,400-mile range and over 100 tons of fuel capacity.

Boeing's MQ-25 Stingray, an unmanned refueling drone, recently completed its first flight. The Air Force is exploring the idea of fully autonomous tankers with no crew, but such aircraft do not currently exist. Lt. Gen. Daniel Tulley, commander of Air Mobility Command, stated that a future unmanned tanker would likely be "huge" and has yet to be built.

The Air Force is currently funding advanced refueling systems at a cost of $13 million for fiscal 2027, replacing the earlier $12 million allocated for a new tanker design. Merlin Labs, a company specializing in autonomous flight systems, is developing software for an autonomous pilot to be installed on the C-130J, an aircraft similar in size to the KC-135.

The C-130J will still carry a human crew, allowing Merlin to gradually introduce autonomy rather than leap directly to unmanned operation. Merlin Labs CEO Matthew George emphasized that certification is crucial for the success of this project. The company is working closely with the Air Force to achieve certification. However, the timeline for a fully operational unmanned tanker remains uncertain due to the ongoing certification process and the current unavailability of an aircraft of the KC-46's size and capacity that can fly autonomously.