2011-02-19

February 4, 2011—The Northrop Grumman-built U.S. Navy X-47B Unmanned Combat Air System Demonstration (UCAS-D) aircraft successfully completed its historic first flight at Edwards Air Force Base, Calif. This event marks a critical step in the program, moving the team forward to meet the demonstration objectives of a tailless fighter-sized unmanned aircraft to safely take off from and land on the deck of a U.S. Navy aircraft carrier , X-47B begins three-year demonstration with first flight over Edwards.

Northrop Grumman marked the beginning of a three-year flight test programme for the X-47B with a 29min flight over Edwards AFB, California, on 4 February. After take-off at 14:09, the unmanned, tailless demonstrator climbed to 5,000ft and validated navigation software and aerodynamic control by flying several racetrack patterns over the base's vast test range. "Designing a tailless, fighter-sized unmanned aircraft from a clean sheet is no small feat," says Janis Pamiljans, Northrop's vice president and programme manager.


The X-47B will move to Patuxent River Naval Air Station, Maryland, later this year after completing a series of tests at Edwards to expand the aircraft's aerodynamic envelope, Northrop says. Meanwhile, a second X-47B test aircraft is scheduled to join the flight test programme. Both aircraft are designed to demonstrate that an unmanned aircraft with a tailless planform can safely operate aboard in the complex operational environment of an aircraft carrier. Carrier trials for the unmanned combat air system-demonstrator (UCAS-D) programme are scheduled to begin in 2013. The first flight event for the X-47B comes ahead of a similar event scheduled for one of its potential rivals, which is also based at Edwards.

Boeing plans to launch a 10-flight test series with the Phantom Ray, a company-funded derivative of the X-45 developed by the US Air Force and the Defense Advanced Research Projects Agency (DARPA). Previous versions of the X-47 and X-45 flew a series of test flights from 2001 to 2004 before the Department of Defense cancelled the joint unmanned combat air systems (J-UCAS) programme.

Program Overview

The X-47B is a tailless, strike fighter-sized unmanned system currently under development by Northrop Grumman as part of the U.S. Navy’s Unmanned Combat Air System Demonstration (UCAS-D) program. Under a contract awarded in 2007, the company has designed, developed and is currently producing two X-47B aircraft. In the 2013 timeframe, these aircraft will be used to demonstrate the first carrier-based launches and recoveries by an autonomous, low-observable relevant unmanned aircraft. The UCAS-D program will also be used to mature relevant carrier landing and integration technologies, and to demonstrate autonomous aerial refueling by the X-47B aircraft.


Autonomous Aerial Refuelling

The US Navy confirms the scope of the Northrop Grumman X-47 unmanned combat air system demonstration (UCAS-D) has grown to add an autonomous aerial refuelling component.

While the refuelling demonstration is only an addition to the carrier suitability demonstration, its sudden approval marks a sea change in the UCAS-D programme's outlook. Only six months ago, a key defence think-tank in Washington DC called a press conference to warn reporters about internal USN plans to terminate the UCAS-D programme as a cost-saving measure.

"We're obviously very pleased that the navy has decided not only to pursue UCAS-D, but to expand it for all the reasons that we outlined in our report," says Tom Ehrhart, a senior fellow at the Center for Strategic and Budgetary Assessments.

That report - published in June by Ehrhart and Bob Work, the centre's vice-president for strategic studies - holds up the UCAS concept as a key technology to ensure the viability of the carrier strike group for the next few decades. Work is now a member of president-elect Barack Obama's national security transition team, and is a widely rumoured candidate for a top job in the Department of the Navy.

The USN launched UCAS-D in August 2007, awarding a $600 million, five-year development contract to Northrop to build two X-47s. The project is limited to a demonstration to prove the viability of operating a large unmanned aircraft on carrier decks.
  
But the navy's plan for a follow-on project has evolved since last year. The original plan called for UCAS-D to be followed by a contract to build an operational system in fiscal year 2014. Last May, the USN unveiled plans to acquire a carrier-based fighter-bomber called F/A-XX after 2020, and named the UCAS-D aircraft as a candidate, along with considering manned aircraft for the same role.

Capt Martin Deppe, the navy's UCAS programme manager, has identified the autonomous aerial refuelling (AAR) capability as a critical enabler for the UCAS to compete for any follow-on contract.

"The navy has not yet decided to procure an operational UCAS system beyond the demonstration," he says. "But, from a theoretical perspective, incorporating AAR capability into a carrier-based UAS unleashes an ability to exploit the range and persistence potential of an unmanned system by allowing it to remain airborne much longer than the limits of human endurance."

With carrier strike groups increasing facing anti-access threats, such as medium-range ballistic missiles, the X-47 could be a technological counter. "A refuellable UAS launching from the carrier flight deck could significantly increase the stand-off of the [strike group] from potential anti-access threats," says Deppe.

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