So. It would appear that DARPA wants to build an American underwater aircraft carrier. You've heard about that one, right? How DARPA wants to find a defense contractor to help it build a submersible carrier that can launch drones, robotic submarines, and rockets from underwater? Well here's something you may not have heard about yet...

We've already got one (sort of). And it's already launched its first airplane.

USS Providence launches a drone from underwater. Source: U.S. Navy NAVSEA-AUTEC

So here are the details. Earlier this month, the U.S. Naval Research Laboratory made a successful test launch of a new "all-electric, fuel cell-powered, unmanned aerial system (UAS)" -- a drone, in other words -- dubbed the eXperimental Fuel Cell Unmanned Aerial System, or "XFC."

The drone started out is mission encased in a Tomahawk missile launch canister, which the nuclear attack submarine USS Providence (SSN 719) fired out of a torpedo tube. The canister then opened, and the drone floated to the ocean's surface. On command, it activated its "Sea Robin" launch system, leaping vertically into the air -- and then happily tooled around the Caribbean on an hours-long test flight, streaming live video back to base all the while. Mission completed, XFC flew back to land safely at the Naval Sea Systems Command Atlantic Undersea Test and Evaluation Center in the Bahamas.

Underwater Aircraft Carrier: Version 1.0
So, is this "mission accomplished?" To an extent, yes. We've proven the concept for one means of deploying drones from "carriers" underwater. We already know that missiles can launch from underwater -- been doing that for decades. And as for the robotic submarines? Right now, they basically look like torpedoes anyway (like the iRobot Seaglider), so it stands to reason they can exit through the torpedo tubes, right behind the XFC drones.

All that remains, really, is to scale up DARPA's project. Build bigger submarine "carriers," with more egress points. Develop new ways to deploy more drones, and deploy them quicker. And of course, pick the right defense contractors to do the work.

What does it mean to investors?
In fact, we already have a pretty good idea of who fits that bill. In this month's drone launch demonstration, the XFC went airborne with help from the Sea Robin launch system built by Oceaneering International (NYSE:OII) -- which happens to also be a leading developer of underwater robots. For drone development, Raytheon's (NYSE:RTN) got a submarine-launched UAV in the works, which it calls the Submarine Over The Horizon Organic Capabilities, or "SOTHOC."

And as for the people who will build the actual aircraft carriers of tomorrow -- the boats that ride below the waves, rather than o'er them, there are really only two companies to choose from: nuke-sub specialists Huntington Ingalls (NYSE:HII), and General Dynamics (NYSE:GD), which incidentally, built the USS Providence itself.

When placing your bets on which companies will win the contracts to build America's future fleet of underwater aircraft carriers, it doesn't get much easier than this.

USS Providence. Source: Wikimedia Commons

Fool contributor Rich Smith has no position in any stocks mentioned. The Motley Fool recommends Oceaneering International. The Motley Fool owns shares of General Dynamics and Raytheon Company. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.