As a fighter plane prepares to take off from a naval carrier at sea, the pilot and deck crew go through a tightly choreographed series of hand signals to tell each other they are ready to launch. It ends with a final “salute” from the pilot to indicate that the aircraft is ready to be catapulted off the deck.
But when the X-47B, the US Navy’s newest prototype combat aircraft, prepares for its first carrier launch early next year, there will be no salute. That’s because there will also be no pilot. Instead, the X-47B will blink its wingtip navigation lights, a robotic nod to the human salute (and mimicking what the Navy does for night launches), before the catapult officer presses the launch button, and the robotic aircraft is flung off the front of the ship
After years of development, and recent land-based tests, the highly anticipated carrier flight for this stealthy, tailless, unmanned drone is imminent. “It should be in early in 2013,” says Carl Johnson, vice president and program manager at defence firm Northrop Grumman, which builds the X-47B. “We have to coordinate ship schedules as well as all the other airspace issues.”
The X-47B is a strike fighter-sized prototype drone developed as part of the United States Navy's UCAS-D (Unmanned Combat Air System Demonstration) programme, which aims to develop technologies necessary to field a combat drone on carriers. As a result, it has folding wings and is built for the rigors of sea life, including salt water, deck handling and of course take-off and landing from an aircraft carrier.
Although the X-47B is a prototype, the Navy hopes to actually field operational unmanned combat aircraft on carriers by the end of the decade.
The unmanned “flying wing” aircraft, which takes some of its design cues from Northrop Grumman’s B-2 stealth bomber, is supposed to demonstrate reconnaissance and strike capabilities—it has a full-sized weapons bay, although the prototype will not fly with weapons. And, unlike existing drones, which are usually remotely “flown” by pilots once in the air, the X-47B is designed to fly autonomously, with just the occasional click of a mouse from an operator to send it instructions.
“It’s a big deal, but it’s an extension of something that was already happening,” says Peter Singer, a senior fellow at the Brooking Institution in Washington, DC, and the author of Wired for War, a book on the military’s robotics revolution.
The craft was revealed in 2008 but is only now undergoing sea tests aboard the USS Harry S. Truman, including moving around on the carrier. Whilst this kind of trial may not sound remarkable, in some ways it’s one of the more challenging steps toward proving that the X-47B, which weighs in at 20,000 kg (44,000 lb) and has a 20m (62 ft) wing span, is ready for flight.
Getting around on a crowded flight deck is difficult, says Johnson, because the aircraft must maneuver very close the edge of the carrier, sometimes pivoting so that it appears that half the airplane is hanging off the ship. “The precision involved in doing that is very difficult with a pilot following directions from a person on the deck,” says Johnson. “It’s very difficult to do that as well with an unmanned system.”
As a result, the engineers have built a wireless remote control device that can be used to move the aircraft around the deck.