Two years ago, the U.S. Navy made a ridiculously unforced error. This year, Northrop Grumman (NOC 2.23%) is going to try to help them fix it.

In 2013, Northrop Grumman's X-47B unmanned aerial vehicle became the first "drone" fighter jet to both launch from and land on an aircraft carrier deck. Over the ensuing two years, X-47B successfully completed 37 landings aboard U.S. aircraft carriers, "and multiple catapult launches, arrested landings, and planned autonomous wave-offs." The wind was at Northrop's back, and it was well on its way to inventing a drone air wing for the Navy.

This all ended in 2015 when the U.S. Navy decided to cancel the X-47B program and retire its two X-47B prototypes -- despite the airframes still having 80% of their expected service life ahead of them. After spending $744 million in taxpayer dollars on the X-47B's development, the Navy was going to simply put the plane on mothballs.

But then a miracle happened.

X-47B drone on carrier deck

Northrop Grumman's X-47B carrier drone is on deck and ready to fly again. Image source: Northrop Grumman.

The Navy's MQ-25A Stingray program -- the carrier-capable drone aircraft that X-47B was designed to become -- began heating back up last year, with Lockheed Martin (LMT 1.69%), Boeing (BA -0.19%), General Atomics, and Northrop Grumman itself all invited to participate. In October, the Pentagon awarded "risk reduction" (i.e. R&D) contracts to all four companies to refine their product offerings.

Now, 10 months later, Northrop has revealed what it will be offering the Navy -- and surprise surprise, it's the X-47B.

Excuse me -- have we met?

Northrop's X-47B doesn't look exactly like it did when last we saw it. As you can see in the photo above, Northrop originally designed the X-47B to be a low-profile aircraft -- a radar-evading, stealthy warbird capable of undertaking surveillance and strike missions sans pilots. But in a controversial decision, the Navy has opted to downplay stealth characteristics on the MQ-25A (which would have been useful in tasking the plane to act as a naval strike fighter) in favor of building a drone to function simply as a flying gas station, refueling Navy F/A-18s and F-35C fighters to do the striking on their own -- sans stealth.

Playing the good soldier, Northrop appears willing to go alone with this plan. After reviewing photos of the company's offering, Aviation Week reports that Northrop has appended to X-47B one very un-stealthy "drop fuel tank" (basically a gas can that can be jettisoned when empty) and one air refueling pod beneath the airplane's wings -- ruining the aircraft's sleek radar profile, but giving it the ability to refuel other planes in flight.

What we know now

Presumably (and hopefully), this inelegant design doesn't represent how the final configuration for how X-47B will look when Northrop offers it to become the Navy's new MQ-25A. But for now, it permits Northrop to resume flying X-47B as a "test bed" while refining its design for the Navy's eventual official "Request for Proposals," due later this year.

Meanwhile, brief glimpses of what Lockheed Martin and Boeing are offering don't seem much better (from a stealth perspective). From the little we've seen, both Lockheed and Boeing are eschewing stealth and working on traditional-shaped aircraft designs, with radar-clogging, wing-mounted fuel pods attached. The fourth company in the running, General Atomics, is believed to be doing something similar -- probably using a Sea Avenger drone as its prototype, and probably affixing fuel pods to its wings as well.

What comes next

All of these designs are of course subject to change, and it's unlikely any of the four companies will finalize their designs before seeing the final, official, Navy Request for Proposals, due out later this year. Once it's been issued, and the companies have submitted their bids, the Navy will study them with an eye to awarding an engineering and manufacturing development contract in 2018. That accomplished, the Navy hopes to begin deploying MQ-25A Stingrays as remote-controlled gas stations for its naval air wings sometime in the 2020s.

The Navy plans to spend as much as $2.2 billion on developing the Stingray through the early part of next decade . Given its experience in building carrier-capable, pilotless airplanes, my money is still on Northrop Grumman to win the contract -- and future production contracts, which one presumes could be worth billions more. The farther the Navy moves away from its original vision of building a stealthy, carrier-capable strike aircraft, however, and the more receptive it becomes to settling for a fleet of lumbering, unstealthy, robotic flying gas stations, the more Northrop's advantages will erode.