The Tactical Technology Office of the Defense Advanced Research Projects Agency (DARPA) issued a request for information on an Airborne Energy Well – an in-flight recharging station for drones. 

The request is aimed at technologies that could adapt existing aerial tankers to recharge Unmanned Aircraft Systems via laser energy beaming. 

This Airborne Energy Well is a potential component of a more expansive energy web of power generation, transfer relays and receiving solutions, enabling the Department of Defense (DoD) to dynamically allocate energy resources to more flexibly deliver military effects,” the request explains. 

In-flight refueling is a routine operation for contemporary military aircraft, with all major air forces fielding large fleets of tankers that can transfer fuel to other aircraft and extend their operating range. 

The US military is currently in the process of adopting the KC-46 Pegasus, a tanker based on the Boeing 767 airliner. It is likely that the new technology is expected to be installed on this aircraft, as older types of tankers – particularly the Boeing KC-135 Stratotanker and the McDonnell Douglas KC-10 Extender – are expected to be retired within the foreseeable future.  

While the majority of combat and reconnaissance drones used and being developed for the US armed forces are jet- or turboprop-powered, the advent of electric aviation likely means electrically powered drones will have an increasingly important role for the US and its allies. 

In recent years there have been numerous experiments to transfer energy via laser beams, including powering drones in a way that would greatly increase their flight time.  

Some of those experiments, including the ones done by the US military, have been done with the explicit aim of powering remotely-operated vehicles over long distances.