The United States Navy’s Unmanned Combat Air System Demonstration (UCAS-D) Program—Born from the former Joint Unmanned Combat Air Systems (J-UCAS) program, the Navy UCAS program will develop a strike fighter-sized unmanned air system that can carry out surveillance and precision strike missions. Under a competitively awarded August 2007 contract, Northrop Grumman Corporation will build two prototype air vehicles to demonstrate that such an unmanned aircraft can be effectively and safely integrated into aircraft carrier-based launch and recovery operations. Success in the demonstration program will set the stage for a potential full scale UCAS development effort in support of the Naval Aviation Master Plan, which includes provisions for the introduction of a Navy UCAS in the 2018 timeframe.
Mission Requirements
Mobile, relocatable, or otherwise “time-sensitive” targets are challenges that the U.S. currently faces in the Global War on Terrorism (GWOT). It is a certainty that because these challenges will increase in number and lethality, the U.S. must develop an effective means to strike them. The single most important system attribute for success against these sorts of time-sensitive targets is broad-area persistence.
Put simply, our forces need to be continuously present across the battlespace to find and destroy targets during very narrow windows of opportunity. And these windows, for many types of targets, such as mobile ballistic or SAM missile launchers, remain open for only minutes at a time.
Looking beyond the GWOT at more stressing projected conflict scenarios, it is clear that U.S. combat aviation forces will need to be capable of establishing persistent surveillance and attack coverage over heavily-defended battlespaces, and in the face of increasingly capable anti-access threats. This is a capability that U.S. aviation forces—regardless of whether they have been based on land or at sea—have never possessed.
To survive when operating persistently in defended airspace, and to retain tactical responsiveness against fleeting targets, future systems will need broad-band/all-aspect low observability. And to fight effectively from beyond the lethal radius of projected anti-access systems such as submarine-launched anti-ship cruise missiles and medium-range anti-ship ballistic missiles, future sea-based aviation systems will need operating radii of 1,500 miles or more — unprecedented for a carrier-based aircraft.
Capabilities Needed
The Navy is investigating UCAS, among other possible solutions, to address these challenges. The UCAS concept uniquely combines the required attributes of persistence, advanced survivability, and long range on a single platform, and does so with an aircraft small enough for carrier basing (see chart A).
Freed from human endurance limits, air-refuelable UCAS systems can be designed to fly 50-100 hours — and perhaps much more — per sortie. At these extreme mission endurance levels, they can efficiently maintain broad-area persistent coverage from well outside the range of projected anti-access threats.
Northrop Grumman’s analysis shows that a single squadron of just 12 UCAS, with their sortie durations conservatively capped at “just” 50 hours, could sustain up to six 24/7 “hunter-killer Combat Air Patrols” – each covering a 200-mile diameter at approximately 1,750 nautical miles from the carrier (see chart B ).
Such extended range will enable a carrier to bring effective combat airpower to bear from blue-water sanctuaries, reducing the requirement for the ship to operate in potentially dangerous littoral regions or choke points. Carrier-based UCASs are likely to prove exceptionally important for operations in Asia, where distances are great and useful bases few. The ability of carrier-based unmanned systems to strike from both the Pacific and Indian Oceans, and to loiter for extended periods, even deep within Central Asia, will deny even geographically large continental opponents the sanctuary of strategic depth.
At the same time, UCAS’ tailless, flying-wing planform design enables signature reductions across all radar frequency bands and aspects – a must for persistence missions over hostile territory.
And of course, unmanned operations negate the risk of aircrew casualties or capture, allowing peace time intelligence gathering with reduced risk of triggering an international crisis. UCAS could be deployed during the critical early stages of a crisis before combat search and rescue assets have been deployed. UCAS could also be deployed during the conflict itself in high-risk missions. With no aircrew risks, UCAS offers a flexible, usable capability across the conflict spectrum.
UCAS can also be employed as a distributed area warfighting system comprised of multiple networked aircraft nodes operating cooperatively. Such a constellation can shore up weaknesses in a broad range of joint mission capability areas. These include, but are not limited to: land and maritime ISR and targeting, communications, time-sensitive ground target attack, maritime interdiction, anti-submarine warfare, fleet air defense, and cruise and ballistic missile defense (see chart C ).
The bottom line is that UCAS will enable Carrier Strike Groups to cost-effectively project global persistent surveillance and attack capability for multiple missions at zero aircrew risk. This would not be just an incremental improvement to naval aviation, but rather a fundamental and transformational revolution.
The Essential First Step: NGC X-47 UCAS-D Program
The capabilities just described have never been demonstrated together in a carrier-capable aircraft. Accordingly, to avoid costly missteps associated with prematurely fielding emerging technologies, the Navy is conducting the UCAS Demonstration (UCAS-D) program to prove the feasibility of the concept. Complementary efforts to fully develop associated and necessary underlying technologies are under way as well. These programs, if successful, will provide future decision makers the option to field UCAS at low risk.
The Northrop Grumman X-47B is the Navy’s chosen demonstration vehicle for validating the UCAS concept. It is a strike fighter-sized platform with attributes directly applicable to what the Navy will ultimately field: a survivable, long range, high endurance, and persistent unmanned system capable of a variety of missions including intelligence, surveillance and reconnaissance (ISR), and time-sensitive targeting and strike.
X-47B will operate above 40,000 feet, fly at high subsonic speeds and have a combat radius of 1,500 nautical miles. In addition to capabilities needed for the UCAS Demonstration, X-47B has an internal payload capacity of 4,500 pounds and provisions for a variety of sensors, including EO, IR, SAR, GMTI and ESM.
Under the UCAS-D program, a Northrop Grumman-led team will show that a tailless, LO-planform UCAS design can be safely and seamlessly integrated into carrier operations. The team will develop an operational-class prototype system – including the X-47B air vehicle, mission control, and support segments – and demonstrate that this unmanned system can perform at-sea catapult launch and autonomous arrested landing operations, pre-launch and post-recovery precision aircraft surface movement, and autonomous carrier-controlled airspace operations.
A world class team with proven experience is in place to help make this happen. Prime contractor Northrop Grumman teamed with Lockheed Martin to capitalize on its strength and experience in all aspects of low observable design and air vehicle survivability. Pratt & Whitney offers proven expertise in military propulsion design and manufacturing, and is providing the F100-PW-220 turbofan engine. GKN Aerospace continues their proven performance in aerostructures manufacturing.
While UCAS-D will constitute a major step forward, it is but one step, and addresses only those technologies associated with UCAS-carrier integration. For UCAS to become a reality, the Navy will need to be supported as it matures and demonstrates a wide range of mission capability-oriented technologies.
At, or certainly near, the top of the list is automated aerial refueling, which underpins the overall UCAS concept by enabling ultra-long mission endurance — and thus both persistence and global range. Other key technology areas include advanced mission management and control, secure wide-band datalinks, highly efficient and ultra-reliable propulsion, miniaturized kinetic weapons, directed energy weapons, advanced sensors, automated targeting tools, and carrier-suitable low observables.
Northrop Grumman is committed to working with the Navy to help drive the technological advances that will make UCAS a reality. The system’s leading edge capabilities will enable the United States to deal with anticipated challenges far more flexibly and effectively. UCAS will revolutionize not only naval aviation, but U.S. power projection in general.
Mobile, relocatable, or otherwise “time-sensitive” targets are challenges that the U.S. currently faces in the Global War on Terrorism (GWOT). It is a certainty that because these challenges will increase in number and lethality, the U.S. must develop an effective means to strike them. The single most important system attribute for success against these sorts of time-sensitive targets is broad-area persistence. 
The Navy is investigating UCAS, among other possible solutions, to address these challenges. The UCAS concept uniquely combines the required attributes of persistence, advanced survivability, and long range on a single platform, and does so with an aircraft small enough for carrier basing (
And of course, unmanned operations negate the risk of aircrew casualties or capture, allowing peace time intelligence gathering with reduced risk of triggering an international crisis. UCAS could be deployed during the critical early stages of a crisis before combat search and rescue assets have been deployed. UCAS could also be deployed during the conflict itself in high-risk missions. With no aircrew risks, UCAS offers a flexible, usable capability across the conflict spectrum. 
The capabilities just described have never been demonstrated together in a carrier-capable aircraft. Accordingly, to avoid costly missteps associated with prematurely fielding emerging technologies, the Navy is conducting the UCAS Demonstration (UCAS-D) program to prove the feasibility of the concept. Complementary efforts to fully develop associated and necessary underlying technologies are under way as well. These programs, if successful, will provide future decision makers the option to field UCAS at low risk.
