The US Marine Corps has selected two bidders - the Boeing A160T Hummingbird and the Lockheed Martin/Kaman K-Max - to demonstrate the ability to move 2,722kg (6,000lb) in less than 6h for three consecutive days.
If either the Hummingbird or K-Max proves acceptable, the USMC is likely to sign the aircraft for a services contract and deploy it immediately to Afghanistan to reduce the need for truck convoys, says Capt Tim Dunigan, commander of PMA-266, the office that purchases multi-mission, tactical UAS for sailors and marines.
"They want to look at results of [the demonstration] and decide if there is a current level of technology that makes sense to take trucks off the road," Dunigan says.
The demonstration, however, could reveal that current technology is not up to the task.
Meanwhile, the USN is also funding studies for a "future cargo UAS" through the Office of Naval Research, Dunigan says. That programme is aimed at developing a dedicated aircraft for the unmanned cargo resupply mission. Northrop Grumman has previously disclosed a cargo UAS concept called the MUVR.
"No-one has developed a large cargo-carrying UAS," Dunigan says, but adds: "Is it hard? No."
At the same time, the USN also is considering adapting the Northrop MQ-8B Fire Scout to ferry supplies between ships, replacing a role played by larger manned helicopters, such as the Boeing CH-46 or Sikorsky UH-60.
"It should come down to a business case analysis in my viewpoint," Dunigan says. "Once you take a look at it that way, the mission can be done by manned and it can be done by unmanned. There really should not be any other driver than how much it costs."
Douglas Fronius, Northrop's Fire Scout programme director, says the MQ-8B must first prove that it can perform its core mission of intelligence, surveillance and reconnaissance (ISR) before expanding its roles aboard ship, but that will come.
"There has to be some core mission where each system buys its way on board because of that [capability]," Fronius says. "Once you have that core mission you expand into other niche missions to expand that capability."