The U.S. Navy has tweaked the specifications of its new robotic warplane, newly stressing its ability evade enemy radars and refuel in mid-air. The result will be a much deadlier killer drone—and one that over time, with upgrades, could grow even more dangerous to America’s enemies.

It almost didn’t work out this way. Way back in 2007, the Navy paid drone-maker Northrop Grumman a billion dollars to build a pair of “demonstrator” robots for tests about the fleet’s nuclear-powered aircraft carriers.

The idea was to gather the data necessary to build the world’s first front-line, jet-powered, armed drone—one with the added ability to take off from and land aboard the flattops’ thousand-foot steel decks.

But before the pair of autonomous X-47B demonstrators—62 feet from wingtip to wingtip, 22 tons fully loaded—began launching and landing on carriers this summer, the Navy seemed to lose its nerve. The follow-on combat-ready robot, known as Unmanned Carrier-Launched Surveillance and Strike, was downgraded to save money.

An X-47B lands aboard the USS George H.W. Bush in July. Navy photo

The Navy dropped the requirement to refuel in mid-air, which would allow a UCLASS drone to fly for more than 12 hours at a time, ranging thousands of miles from its home carrier. The sailing branch also exempted the next-gen robot from flying and fighting in heavily-defended enemy territory. Instead, UCLASS would be meant for “lightly contested” airspace.

As conceived this summer, UCLASS would have been best suited for scouting a modest distance ahead of the fleet, or alternatively prowling over poor countries searching for terrorists and insurgents who possess little ability to detect or shoot at aircraft and ships. The ‘bot would not have been meant for a major war with, say, Iran or China and their legions of radars, missiles and jet fighters.

Bob Work, an influential former Navy undersecretary rumored to be up for a top Pentagon posting, expressed his preference for a drone that can fly farther and evade stiff enemy defenses—in other words, a true warrior rather than an assassin spy. “You can’t afford both. You have to make your bet,” said Work, currently heading the Center for a New American Security think tank in Washington, D.C.

In betting on the lesser drone, the Navy seemed to be giving in to the fear of the unknown. Long accustomed to old-school, man-in-the-cockpit flying, the sailing branch has been a relative late-comer to the drone world. Navy leaders are particularly worried about mixing sophisticated robots and manned planes on the same chaotic 4.5-acre carrier decks.

Congress knows what it wants: a drone that’s a real ass-kicker. “We believe the current path could limit the capability growth of the system,” the House Armed Services Subcommittee on Seapower and Projection Forces wrote to Secretary of the Navy Ray Mabus in September in reference to UCLASS. The letter was signed by chairman Rep. Randy Forbes, a Virginia Republican, and ranking member Rep. Mike McIntyre, a Democrat from North Carolina.

Mabus wrote back, promising to “work closely” with Congress on refining the killer robot. And for once, the fleet’s bureaucracy meant what it said. On Nov. 12, War is Boring’s own Dave Majumdar, writing for the U.S. Naval Institute’s news blog, reported that the Navy had changed its drone plan, opting for a deadlier design including both stealth and mid-air refueling.

An X-47B aboard the USS Theodore Roosevelt in November. Navy photo

“What we want to do as an affordability initiative is to ensure that the air vehicle design upfront has the growth capability without major modifications to go from permissive to contested [environments],” Rear Adm. Mat Winter, the Navy’s top drone manager, told Majumdar.

Winter added that he had contacted all the aerospace contractors vying for the UCLASS contract—Northrop, Boeing, Lockheed Martin and General Atomics—requiring them to show how they would ensure that the front-line robots they’re proposing to build would perform over long range and against heavy defenses, especially with progressive upgrades.

Having chosen the tougher drone, the Navy is altering its research plan. The two X-47Bs, one of which is currently aboard the East Coast carrier USS Theodore Roosevelt for flight testing in windy conditions, had been slated to also go to sea twice more: in late 2014 and again in 2015.

Among other things, those trials would have emphasized “fleet visibility,” according to an internal Navy document obtained by War is Boring—essentially, just exposing sailors to the robots for the humans’ comfort.

But now aerial refueling is the new focus, and the two future carrier visit are most likely cancelled, according to a program insider. “We’re done with boats,” he said.

According to the leaked document, the X-47Bs could refuel from tanker aircraft in mid-air as early as the fall of 2014. The resulting test data will be provided to the contractors so they can prep their UCLASS designs for refueling, too.

With the shift from a “lightweight” drone to a tougher, war-ready model, the Navy is signalling its intention to deter and win even the most intensive, high-tech wars. The sailing branch is also committing to truly advancing the state of the art of robotic technology to produce the best and most capable autonomous warplane.

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