DARPA wants to refuel drones in flight – wirelessly

US military researchers are trying to turn in-flight refueling tankers into laser-shooting "airborne energy wells" for charging drones, and they want the public's help to figure out how.

The Defense Advanced Research Projects Agency (DARPA) published a request for information (RFI) from anyone willing and able to contribute their tech, with a few caveats. It needs to fit on existing in-flight refueling tankers (the newer KC-46 and Cold War-era KC-135, specifically) and be able to deliver 100kW of power.

Militaries around the world have been using in-flight refueling for decades to extend aircraft patrols and long-range missions. With a history of development stretching back to the 1920s, the practice has since developed into a standard part of operating an air fleet powered by aviation fuel.

Where traditional air-to-air refueling requires booms, hoses, and other equipment, DARPA sees any potential laser power-beaming device as something small, like an underwing pod. The RFI reveals the DoD has already been exploring wireless energy transfer tech for its "unmanned aerial systems," and that wireless sky charging could lead to drones that are lighter thanks to not needing as much onboard battery capacity.

DARPA sees its airborne energy well as a component of a much larger web of power generating, transfer, and receiving technologies that would enable "the DoD to dynamically allocate energy resources to more flexibly deliver military effects."

With plans seemingly built around a piece of technology that has not yet been invented, DARPA isn't wasting time collecting concept sketches: it has a strict list of three things it's looking for.

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First, DARPA only wants tech that can identify existing or required equipment needed for the retrofit, and it wants data on the limits of how much power it could generate. It also wants systems already able to generate the "100kW or greater continuous wave laser as well as the thermal control" that would be necessary for operating in the air.

Second, DARPA wants tech with a specific laser solution able to deliver 100kW or more, and it wants equipment that can "provide beamforming and steering of the laser energy to remote locations and covering a nearly hemispherical field of regard."

Those two combine for DARPA's third requirement, that all the bits needed to build its airborne power zapper be at least at a tech readiness level of 6 or higher, meaning the components have been demonstrated successfully in a relevant environment.

Not only does it want ideas as close to deployable as possible, DARPA also isn't giving interested experimenters much time to deliver what it's asking for: submissions are due less than a month from now on July 11. ®