Correction: A previous version of this story incorrectly described Maj. Gen. Michael Lundy's status with the US Army. He has not retired, and his next assignment has not yet been announced.

WASHINGTON — The Army is conceptualizing an "ecosystem" framework tying all future unmanned aircraft systems together on the battlefield, according to the service's Training and Doctrine Command capability manager for UAS.

A draft document outlining initial capabilities that establishes what is needed for a family of UAS in the 2020 to 2035 time frame and beyond is circulating through the Army staff, Col. Thomas von Eschenbach told Defense News.

A key piece of the capabilities document would establish what the service is calling "a scalable control interface" that simplifies the coordination of UAS on the battlefield and is easy to use. Most Army UAS types have separate control stations.

The most important part of establishing a family of systems for the future is "how we [are] defining not necessarily what unmanned systems do," von Eschenbach said, "but it really defines for us how we want to operate unmanned systems from that scalable control interface. I think that was a thing that was missing in the past, what we didn't really think about."

Beyond that the Army is still considering what UAS it needs in the battlefield of the future, what it will want these UAS to do to meet its missions in a more expeditionary and access-denied environment and what technology is out there to bring more capability to the aircraft.

"In terms of where the Army's headed, it's not entirely clear at this point because if you look at what the Army's investing in, it's not much in unmanned systems," Phil Finnegan, a defense analyst at the Teal Group, said. "There's a little bit going into Shadow [UAS] for a new engine, but they just finished procurement of Gray Eagle. There doesn't seem to be much interest in purchases of the minisystems that Aerovironment does."

Von Eschenbach said the Army is taking the time to think deeply about what it needs for UAS in the future and to learn through experimentation.

The service started off using UAS for ISR missions because they were well-suited for that kind of mission, von Eschenbach said. "It was long-range, long-endurance with some very simple technology that has grown and as we see technology kind of enabling us to shrink those components lighter, you are able now to start to explore and discuss what else can our unmanned systems do and do we want to pursue that and expand that into the Army missions."

Here's a deeper look at what the Army is considering for its future UAS.

Runway Independence

There’s little doubt the Army will have to operate in places where it can’t rely on protected runways, or runways at all. "I don’t want to be on runways anymore," Maj. Gen. Michael Lundy, previous commander of the Army Aviation Center of Excellence at Fort Rucker, Alabama, said at a recent event in Arlington, Virginia, prior to his retirement.

For Lundy that seemed to mean a vertical-takeoff and landing (VTOL) capability that is more survivable; has a reduced signature, making it less detectable; and requires fewer people to run UAS. He noted that "speed is not that big of a deal."

The idea of the Army moving toward VTOL UAS options is a big shift from the recent past when the service has struggled to develop the capability. The Army has shelved VTOL UAS several times following some embarrassing failures.

The Army's Boeing-made  A-160 Hummingbird VTOL UAS, with an expensive, state-of-the-art Defense Advanced Research Projects Agency camera on it, crashed in California in 2012, which didn't bode well for the program.The crash marked its third in two years. Adding to its bad track record, there were also reports of a fire on the A-160 assembly line.

The Army canceled its plan to deploy the A-160 to Afghanistan shortly after the 2012 incident.

The service also considered procuring Northrop Grumman's Fire Scout UAS program, but then lost interest in it and canceled the program.

Acknowledging the Army's struggle with VTOL UAS, von Eschenbach said, "that is the challenge. How do you get something that has this long endurance, long time in the air that also has the ability to do a vertical takeoff and landing and that is probably a very difficult challenge to overcome."

The Army is closely watching a DARPA effort to develop VTOL UAS capability. DARPA selected last month Aurora Flight Sciences to build its unmanned X-plan that will take off and land vertically. Renderings of the design — LightningStrike — show that it is far from a typical VTOL design. The team has 24 months to develop the aircraft.

Von Eschenbach said that if something like DARPA's design is a game-changer, the Army will do what it can to get the capability.

Yet the Army is willing to look at trade-offs. "If it's short-takeoff and landing versus VTOL, what does that mean? And certainly we will take a look at it and then at that point in time we will entertain what is in the realm of the possible and affordable," he said.

Gen. David Perkins, Army Training and Doctrine Command commander, said that VTOL isn't the only solution to achieve runway independence. "VTOL is one of them, but there are other things out there," he said. "There's the proverbial catch it in a net, things with parachutes, there are other ways of doing it. It's challenging, that is why we are tied to a runway. That is actually the hardest part, that is why we haven't solved that yet."

Cargo Resupply

For large-scale operations in ground combat, Army Chief of Staff Gen. Mark Milley has said that cargo resupply using unmanned systems is particularly promising.

Whether those unmanned systems are primarily ground or air vehicles remain to be seen as the Army is eyeing both.

Yet, Lundy was lukewarm at a recent conference when it came to giving UAS the resupply mission in the near-term. He noted the Army seldom flies purely cargo missions and said, "I can't have an unmanned cargo aircraft moving soldiers."

Lundy's sentiment is indicative of the Army's more sideline approach to unmanned aerial cargo resupply.

The Army has done and continues to test cargo resupply capabilities as well as other possibilities, like casualty extraction, for Lockheed Martin's K-MAX VTOL UAS, but when it came down to testing its ability in theater, the Marine Corp took the reins.

Jon McMillen, who leads Lockheed's business development for K-MAX, said that aircraft returned from Afghanistan after 33 months in mid-2014 having hauled 4.5 million pounds of cargo and flying over 1,900 sorties.

Despite a hard landing that took one of the two K-MAX aircraft out of commission for a time, the entire deployment "surprised a lot of people in how well it performed," McMillen said.

The Marine Corps is continuing to study the K-MAX's utility to inform a future program and the Army has followed along in the process and continues to watch the effort, according to McMillen.

The Big Battlefield Picture

No matter what UAS is on the battlefield performing whatever mission it's ultimately assigned, operating them has to be simpler and has to be better coordinated, von Eschenbach stressed.

That's where the scalable control interface comes in so that UAS operators can control any UAS on the battlefield wherever they are. Operators would be able to fly UAS and operate payloads while sitting in the back of a moving vehicle, for instance, von Eschenbach said.

Operators will no longer be tied to elaborate and heavy ground control stations that prohibit easy movement in the field and only work in uncontested environments where the station is protected.

The new interface would also improve data dissemination coming from UAS to the right decision-makers on the ground and to troops who need the information to conduct missions.

Essentially, the operator would maintain "the heartbeat of the unmanned systems" in an operational picture, he added.

Twitter: @JenJudson