FORT SILL, Okla., -- Imagine a Stryker out on the battlefield goes down with a broken component within its drivetrain. The maintenance team is working on it but they need a part from the rear. Easy enough. You could gather an entire convoy, go through convoy-planning missions and actually get on the road -- or -- you could load a single piece of equipment on a drone and send it from point to point.

That scenario is one Bob Forrester, with the Army's Armament Research, Development and Engineering Center, has envisioned while at the Maneuver Fires Integrated Experiment (MFIX) at Fort Sill. The event took place April 3 through 13 and experimented on, among other things, the ability to use unmanned aerial vehicles, autonomously, to deliver supplies to service members.

"The Army is not necessarily developing these capabilities," said Forrester. "This is coming out of industry. It's in the news. There are systems coming online that are flying people -- that are flying supplies. Big companies are coming online so the military is trying to harness that and trying to understand how can we use that to effectively change the way we do business for tactical distribution."

The focus of the experiments has been to determine how to provide resupply for units at "the last tactical mile" said Forrester. Keeping squads and platoons in mind, Forrester and his team have been trying to answer, what is the relevant amount of supplies for these units and how can those supplies be delivered?

To find the answer, a spectrum of prototype unmanned aerial vehicles, called joint tactical autonomous air resupply systems (JTAARS) was experimented on. Rather than a single piece of hardware, Forrester hopes to provide a family of systems, several different prototypes, each with different technical approaches and capabilities and able to carry between five and 600 pounds. But first the right combinations and mixtures of types of drones and capacities needed to be determined. Capt. Dustin Dunbar, with the Combined Arms Support Command Sustainment Center of Excellence, and other Soldiers were invited to help determine what those combinations and mixtures might be. Bulk supply would not be capable with JTAARS, however smaller-scale supplies would be feasible.

"Bulk supply would be class 1 water, class 3 bulk fuel," said Dunbar. We're looking more at class 5 which is ammunition and class 9 which is repair parts."

Not only were new technology (UAVs) experimented on, but they also evaluated if units, who previously had no requirement to understand airspace, would be able to operate a UAV. While at MFIX, the JTAAR systems was experimented against a number of units competing for airspace while simultaneously evaluating if Soldiers who had no experience with air coordination, would be able to handle the added mission set. Those responsibilities included maneuvering around other drones, communicating with anti UAV units or even contacting units organic to Fort Sill that were conducting Howitzer training.

For Dunbar, the defining requirements of using UAVs for resupply had to include autonomy and be user friendly. For example, when an infantryman is receiving supplies from a JTAAR vehicle, he must be able to easily re-task the drone or, the drone lands, unloads and then the Soldier presses a button and it automatically flies back, said Dunbar.

Another area of experimentation is how to track a drone without using a GPS. Having a system in constant communication with a ground-control system, such as a laptop, means there is a signature being pushed out which makes it more capable for an enemy to detect. Forrester said the experimentation included determining how to operate in environments without GPS and other communication abilities.

Forrester said finding other forms of fuel, beyond batteries, is another area to develop but the system is still in its early research and development stage (about three years). Still they have made advancements, starting with systems on the smaller end of the spectrum and then moving toward larger systems. The next step is for those Soldiers who experimented with the equipment to identify what exactly the capabilities are within the military and what technology can be provided. After MFIX the plan is to return with lessons learned and create doctrine that may take the system from experimentation to an actual piece of equipment used by the military (a program of record).

"There is the technical ability and then there is the adoption into the field of a program of record," said Forrester. "Technically, if you look across the news, within two to three years you're going to see large-capacity systems flying, so technically we're probably a couple of years out."

However, being able to technically create the drones does not equate a program of record. The adoption into the Department of Defense requires analyzing how the force structure may need to change, how to effectively utilize these systems and how to get funding to purchase it, said Forrester.

"There's a lot of process that needs to happen before we can adopt it into the military," he said. "What we're doing is we're trying to understand the solution space. So the more prototypes, the more samples, the more types of systems we can provide the better so we can understand the right mixture of capabilities and technologies to really provide what the warfighter eventually needs."