X-47B scheduled to launch at sea in 2011
SAN DIEGO — It will be a much-watched but close-hold event in the Mojave Desert north of Los Angeles in November, when the unmanned bomber drone takes to the air for its first real flight sortie.
That maiden flight of the X-47B at Edwards Air Force Base, Calif., will be a key milestone in its test program. Its next critical test will be landing on an aircraft carrier at sea.
The batwing X-47B is Northrop Grumman’s design for a tailless, pilotless autonomous aircraft that can remotely launch and recover aboard aircraft carriers. The aircraft, which Northrop Grumman and the Navy in December unveiled as the UCAS-Demonstrator — short for unmanned combat air system — will go “wheels up” in early November.
Sea trials are planned to begin in 2011 on the East Coast aboard the carriers Harry S. Truman and Dwight D. Eisenhower, said Tim Beard, a retired rear admiral and pilot who is leading Northrop Grumman’s X-47B program on carrier integration.
In 2007, Northrop Grumman got a $636 million Navy contract to build a carrier-based aircraft and inherited a UCAS program worth $809 million that “all of a sudden got sea legs,” Beard said.
Starting this fall, the aircraft will spend six to eight months flying at Edwards. It will then go to Naval Air Station Patuxent River, Md., for testing and flights through November 2011, as well as additional testing at Naval Air Engineering Station in Lakehurst, N.J., Beard said. Contractor crews plan to put the aircraft aboard a carrier at the Norfolk, Va., naval base to evaluate “all the stuff you have to do to get ready to get aboard a ship,” he said.
Simulated sea duty
Even before it encounters the salty sea air and swells for real, the X-47B is launching and landing on simulated Nimitz-class aircraft carriers, events computed and conducted by designers and technicians at Northrop Grumman’s desert plant in Palmdale, Calif. Computer simulations and F/A-18 Hornets configured with software to fly like the X-47B have done 10,000 successful virtual landings, grabbing the same wires that trap piloted aircraft on a deck busy with personnel in shifty sea conditions, Beard said.
It’s not just about building an aircraft with systems able to withstand the rigors and harsh conditions at sea.
“We have to get an aircraft that is survivable in the at-sea” environment, Beard said, and one that fits well with sailors in the hectic work environment of the flight and hangar decks.
So aircraft designers and technology developers will use simulation and shore-based testing, at-sea flights and input from sailors to answer questions such as how a crew would refuel, service or move the aircraft.
“Have we designed them well so the kids can service them on the flight deck?” Beard said. “We have worked at the enlisted level and we’ve worked at the junior officer level. We had to sell them. They’re not sold yet. This is a huge leap.”
While the military’s fleets of unmanned aerial vehicles continue to grow, the X-47B, with twin bays to carry two precision-guided munitions, would be the Navy’s first unmanned strike aircraft. It also would be the first to launch and recover at sea, on carriers that for generations have been the bastion of manned aircraft. Beard said the pilotless aircraft, with its “cranked kite” design, is planned to complement manned aircraft and ultimately will fit into a carrier air wing populated by F-35 Joint Strike Fighters.
The unmanned bomber, unencumbered by flight-hour restrictions, is designed to fly farther and have a longer loiter time — to tackle multiple targets or perform multiple duties in combat zones — than manned aircraft.
Recent simulations have shown that the aircraft completed about 17.5 hours “time on station” during a 47-hour flight that included six aerial refuelings, he said. A manned jet would get 30 minutes of time on station during an 11-hour mission.
“We are fairly confident that we can get 50 hours out of the existing aircraft,” Beard said. “You get a massive increase in mission endurance.”
The X-47B will be less burdensome on maintenance as well, Beard said.
The X-47B is a unique aircraft, but it won’t be totally unfamiliar to some experienced sailors.
The X-47B is designed and built with the same hook used on the now-retired F-14 Tomcat jets, Beard said, and it borrows other elements of the Navy’s manned-jet heritage, with S-3 tires, F/A-18 tires and brakes and F-22 generators.
With weight similar to an F/A-18C Hornet and a wingspan two feet short of the Tomcat’s, it has a wider but shorter footprint than existing aircraft and wings that “fold just like an EA-6B,” Beard said.
About UCAS
The X-47B unmanned combat air system is designed for aerial reconnaissance, surveillance and targeting, all without a pilot aboard. Flight testing begins in November, with the first carrier landing set for 2011.
• Power plant: Pratt & Whitney F100-PW-220 turbofan engine.
• Top speed: High subsonic.
• Combat radius: 1,500 nautical miles.
• Top altitude: 40,000 feet.
• Payload: 4,500 pounds internal.
