J-UCAS Overview




The Joint Unmanned Combat Air Systems (J-UCAS) program is a joint DARPA-Air Force-Navy effort to demonstrate the technical feasibility, military utility and operational value of a networked system of high performance, weaponized unmanned air vehicles to effectively and affordably prosecute 21st century combat missions, including Suppression of Enemy Air Defenses (SEAD); Electronic Attack (EA); precision strike; surveillance/reconnaissance; and, persistent global attack within the emerging global command and control architecture.  The operational focus of this system is on those combat situations and environments that involve deep, denied enemy territory and the requirement for a survivable, persisting combat presence.


The J-UCAS program combines the efforts that were previously conducted under the DARPA/Air Force Unmanned Combat Air Vehicle (UCAV) program and the DARPA/Navy Naval UCAV (UCAV-N) program. The Defense Department recognized the potential for significant synergy by combining the programs, and in 2003 directed that the programs be consolidated into a joint demonstration program supporting both Navy and Air Force needs.


"J-UCAS is a key transformational program within the Department of Defense’s portfolio. The capabilities offered by this family of systems can have profound implications on the Department’s future warfighting capability and force structure."
– Mr. Michael W. Wynne, USD(AT&L) (Acting), 23 June 2003


Operational Capability


The J-UCAS vision is for a lethal, unmanned system-of-systems that expands mission options and provides revolutionary new capabilities for air power projection into deep, denied enemy territory and other extremely dangerous adversary domains.  The program is focused on diverse missions in these environs, including suppression of enemy air defenses, or ‘SEAD’; electronic attack; penetrating surveillance; and other related missions requiring timely strike capabilities.  The J-UCAS weapon system will exploit the design and operational flexibility of unmanned combat air vehicles to enable a new paradigm in warfighting that blends advanced technologies to achieve highly autonomous operation, yet retains the judgment and decision authority of the human operator, especially where lethal force application is invoked. The system will be capable of dynamic mission re-planning and responsive execution employing varying levels of autonomy.  The J-UCAS Program has been designed to fully exploit the technological advances emerging from the ongoing information revolution, so as to provide new options for advanced airpower projection that can support a variety of military missions anticipated in the years ahead.


As a “first day of the war” force enabler, J-UCAS air vehicles will support and complement strike packages by finding, identifying, tracking and targeting enemy air defense elements, and negating them through either lethal and non-lethal means.  J-UCAS is being designed to accomplish preemptive destruction and/or electronic suppression of sophisticated enemy integrated air defense systems (IADS) using a variety of sensors and weapons. These SEAD and electronic attack missions are of high priority for the U.S. Air Force.  As the campaign progresses, with its distributed platform presence, J-UCAS will provide continuous vigilance with an immediate lethal strike capability to prosecute high value and time critical targets.  J-UCAS could also be used in support of peacekeeping activities such as enforcing “no-fly” zones, and other missions, which typically entail flying long hours of patrols (so called “dull” missions).


J-UCAS is also being designed to provide persistent surveillance, reconnaissance, and targeting to complement manned assets and long range precision strike weapons, operating and surviving in denied airspace.  This persistent intelligence, surveillance and reconnaissance (ISR) mission is of paramount importance to the U.S. Navy, so a carrier-based variant is crucial.  To fully exploit its potential and “buy its way” onto the carrier, SEAD and deep strike capabilities will be designed in from the outset and fully developed in future versions. The system will be seamlessly integrated with manned aircraft missions, carrier air traffic control, and deck operations, as well as with the carrier’s C4ISR architecture.


Many of the technical challenges faced by J-UCAS are common across the range of its projected missions. These include the development of affordable, low observable air vehicles capable of dynamic distributed control using advanced cognitive aids and advanced targeting processes. J-UCAS will also be interoperable with other manned and unmanned military systems. It will feature a secure, robust communications capability, but will also have the ability to conduct adaptive, highly autonomous operations, including coordinated multi-vehicle mission activities. The system will exploit significant improvements in reliability-maintainability technologies and processes, robust prognostics and health management systems to reduce manpower and other system support costs, minimize turnaround time, and facilitate a rapid sortie generation rate.


System Attributes

The J-UCAS Program is developing an integrated system incorporating multiple platforms and control stations, wirelessly linked to achieve shared, interactive control and capable of operating over global distances.  J-UCAS air vehicles are equipped to accommodate a variety of sensors and payloads in order to provide the flexibility necessary to address diverse mission requirements.  Resultant capabilities will be demonstrated in the Operational Assessment scheduled to begin at the end of FY2007.


J-UCAS will employ a Common Operating System to integrate the system components (e.g. platforms, subsystems, sensors, weapons, communications, and human crews), providing the necessary software and services that enable system functionality, while minimizing the impact of platform constraints.  J-UCAS will exploit a system architecture designed to ensure intra-operability between the internal J-UCAS system elements and inter-operability with other external systems such as manned aircraft, command and control centers, and other relevant assets – be they airborne, space-based or ground-based.  Based on a single, common architecture, the demonstration program will also seek to exploit a common suite of sensors, accompanied by common avionics and related software applications, and a Common Operating System to reduce costs, lower barriers to the entry of new technology into J-UCAS, and an accelerate this network centric war fighting capability.


The J-UCAS Capability Demonstration Program will employ two complimentary air vehicle “families” to explore and assess the operational possibilities associated with this new war fighting concept.  Air vehicle developer-integrators Boeing (X-45 family) and Northrop Grumman (X-47 family) have been challenged with demanding range-payload performance and survivability objectives.  These include the following common performance objectives for the operational assessment demonstrator aircraft:


  • Combat Radius: 1300 nm
  • Persistence: 1000 nm with 2 hrs loiter
  • Payload: 4500 lb

J-UCAS is being designed with a focus on affordability, in both the acquisition and operations and support (O&S) areas.  Removing the pilot from the vehicle eliminates man-rating requirements, human support systems and other pilot interfaces. New design philosophies can be used to further optimize the design for aerodynamics, signature, and reduced maintenance, as well as embrace low cost manufacturing processes.  The program’s focus on precision engagement and weapons capabilities should result in reduced target geolocation errors, use of smaller weapons, ability to attack multiple targets during a single mission, all while reducing the possibility and costs of fratricide. Improvements in sensor technologies will also allow significant advances in surveillance and reconnaissance over high threat areas. J-UCAS will be highly effective with a significant reduction in life cycle costs over current systems. 


Operational Experimentation & Assessment


Today’s J-UCAS Capabilities Demonstration Program is built on the lessons learned from the first generation of J-UCAS air vehicles built by Boeing and Northrop Grumman, the X-45A and X-47A, respectively. Early operational experimentation and assessment activities will be conducted using the improved follow-on air vehicle designs - the low observable X-45C and X-47B demonstrators. These newer platforms are designed to provide significant increases in payload, range and persistence, as well as improved simulation, mission control and support systems.


The Operational Assessment (OA) Phase of the J-UCAS Program will begin as the air vehicles mature in flight and their ability to conduct mission operations.  OA activities are currently scheduled to begin in the last quarter of CY2007.  In reality, operational user involvement in the program will begin earlier with their participation in advanced interactive system simulations that provide both operator orientation and feedback.  These simulation activities will also prove useful in the development of future operational methodologies and tactics, and will have a significant influence on the software being developed to operate and maintain the system.  The OA is expected to extend to the end of the current decade and beyond, depending on development progress and feedback from the operational community.


Development History


DARPA-Air Force UCAV -- Boeing X-45A – The Boeing Company won the initial competition for the Program’s Advanced Technology Demonstration (ATD).  As a result, two Boeing X-45A air vehicles were built to demonstrate the requisite technologies necessary to conduct projected SEAD and strike missions.  The evolution of this capability continues to occur through the flight-testing of four increasingly capable software blocks. X-45A’s first flight occurred in May 2002.


Each vehicle has one working weapons bay, with an avionics pallet located in the other bay. The vehicles are all electric, except for the nose wheel steering and hiking system. The engine is fed through a serpentine inlet and uses a yaw thrust vectoring system. The two X-45As have demonstrated the basic functionality of the command and control, and communications and navigation systems, as well as the aerodynamic envelope required for future demonstrations. X-45A command and control is effected through a dual-display control console, which is mounted in a trailer-based environmentally controlled shelter.  Characteristics of the X-45A are shown below:

Boeing X-45A Characteristics

Navy UCAV-N -- Northrop Grumman X-47A Although the DARPA/Navy UCAV-N program focused mostly on system studies, a single X-47A air vehicle was built independently by Northrop Grumman and tested under the program’s auspices. Demonstrations included low-speed handling qualities, air vehicle performance and precision navigation capability. A tailhook arrestment, typical of that required for carrier flight deck operations, was successfully simulated by landing the X-47A near a pre-designated touchdown point, utilizing the shipboard-relative global positioning satellite (SRGPS) system as the primary navigation source to achieve extremely precise landing capability. First flight took place in February 2003. Characteristics of the X-47A are shown below:

Northrop Grumman X-47A Characteristics

Boeing, the other participant in the UCAV-N effort, developed a carrier-based air vehicle concept – the carrier-compatible X-46, as its entry into the Navy’s UCAV program.


Current Development Activities


Second generation J-UCAS demonstrators are now under development as part of the J-UCAS Capabilities Demonstration Program.  The Boeing X-45C and Northrop Grumman X-47B are the planned next steps in the evolution of affordable, operational J-UCAS air vehicles. The X-45C and X-47B are designed to take affordable stealth to the next level and to provide representative configurations of persistent, long range tactical sized aircraft compatible to meet contemporary Air Force and Navy operational expectations. The larger air vehicles will more closely represent the envisioned operational systems, to include sensors, two full weapons bays and incorporation of low-observable (LO) technologies.  They will be used extensively in the operational experimentation and assessment activities that follow.


Boeing X-45C Under the original DARPA/Air Force UCAV program, the Boeing team created the X-45C, based partly on its X-46 design that had been developed for the UCAV-N. The X-45C weighs approximately 36,000 pounds, with a wingspan of nearly 50 ft, and can carry up to 4,500 pounds of ordnance. The X-45C design completed its Mid-Term Design Review in December 2003. Boeing proposed a modified version of the X-45C for Navy use.

Boeing X-45C Characteristics


Northrop Grumman X-47B The Northrop Grumman/Lockheed Martin team was initially focused on a carrier capable UCAV to meet the Navy’s need. The “cranked kite” design shows its clear ancestry to the X-47A, with the addition of winglets to improve low speed handling and endurance of the vehicle. Weighing over 42,000 lbs with 4,500 lbs of weapons payload, it defines the larger end of the current J-UCAS family of vehicles. The X-47B team completed its System Requirements Review in December 2003. Northrop expects a very high commonality between its vehicles for Navy and Air Force use.



Northrop Grumman X-47B Characteristics

Common Systems & Technologies


Common Systems & Technologies – The use of common elements are not unusual for a joint program with the need for achieving interoperability and the other advantages to be realized from economies of scale.  However, the network centric nature of the J-UCAS, with the need for collaboration and synchronization, coupled with demanding mission timelines, drives the need for a Common Operating System (COS) and common sensors. 


Common Operating System (COS) The J-UCAS concept is unique among UAV systems primarily in its use of an “operating system” as the central integrating mechanism for the major system components.  Traditionally, UAV systems have been designed around their hardware architectures, with federated software components to match the hardware elements.  The J-UCAS Program is acutely aware of the pivotal role of information technology as an unmanned systems enabler, as well as its strengths, weaknesses and cost implications.  Taking a lesson from the commercial IT world, the Program has chosen to develop the key ‘connect-the-dots’ software elements as a single, integrated system in much the same manner as the standard desktop computer model.  The operating system, in this case, provides architecture, algorithms, software, and services that comprise the system’s core integrating functions.  The latter include:

          Control/Manage System Resources

          Facilitate Information Exchange

          Provide Battlespace Awareness

          Enable Inter-platform Collaboration

          Enable Autonomous Operations

          Maintain Quality of Service (Network)


A major factor motivating the development of a Common Operating System (COS) is the level of integration and interoperability embedded in the J-UCAS concept. J-UCAS is not a single ground station and a single platform, but a collection of platforms, as well as multiple control elements all linked together with the infrastructure and support systems to provide a single, seamless integrated capability.


The system should be versatile in performing its various mission functions. The J-UCAS elements therefore, have to be intra-operable as well as inter-operable with outside elements of the system. Another motivating factor for the COS is the level of autonomy versus human-in-the-loop operation needed during the operation of the J-UCAS.


The balance between autonomy and human interaction is dictated by the actual mission itself and a COS is needed to manage this balance. This COS is being designed so that it can, in effect, host a number of other configurations that might be required to pursue missions of a similar type as we move into the future and the requirements for the existing platforms change.  The COS development brings the best of the two air vehicle developers, Boeing and Northrop Grumman, together with other pre-eminent technology providers in a collaborative endeavor to create the world’s most advanced unmanned system mission planning and control capability.



The J-UCAS program has formed a consortium involving these entities along with a third entity termed the COS integrator/broker (I/B). The Johns Hopkins University-Applied Physics Laboratory was competitively selected to fill that role. The Program’s air vehicle primes are key stakeholders that will directly contribute software functionality to the COS and are exclusively responsible for integrating the COS into their respective platforms. Technology contributors will compete to provide “best of breed” algorithms to the COS, giving it the opportunity to host most advanced functionality achievable. Their involvement in the consortium is based on the specific potential contributions that may enhance the COS functionality.


Technology providers may include small developers, other large defense contractors, as well as traditional sub-contractors. The integrator/broker role is intended to facilitate the COS integration process among the other consortium members. The integrator/broker is charged with acting as the consortium’s honest broker - facilitating, coordinating, and (if necessary) completing the development of the J-UCAS enterprise architecture and COS.  The I/B is responsible for maintaining configuration control of the COS, as well.  The I/B must exhibit extensive domain knowledge and expertise in the areas of sensors, communications, and real-time embedded systems.

Program Management


The J-UCAS program is led by a joint team headquartered at DARPA. The J-UCAS Office, under DARPA leadership and with support from the Services -- was formally stood-up in October 2003, and is focused on planning and conducting a Capabilities Demonstration Program culminating in an operational assessment that supports both Navy and Air Force emerging requirements. This assessment will provide the Services with several program options in the FY07-10 timeframe.


The development and evolution of requirements is a critical part of the J-UCAS program. A joint Operational Advisory Group (OAG), comprised of the Air Force, Navy and Joint staff representatives, is integral to this continual refinement of the program’s objectives, desired capabilities, and priorities.  Similarly, the development of the Operational Assessment Plan is an ongoing process led by a coordinated group of program office, development testers, operational testers, and other Service representatives. The results of the Operational Assessment will be key to subsequent decisions that define desired capabilities and expectations for follow-on operational system development. Both activities are accountable to the Services’, but provide input directly into the J-UCAS Program Director.  The goal is a blend of system innovation, concept exploration, and operational experimentation that will enable DoD leadership to chart the course for unmanned combat air systems into the next decade.


Point of Contact


For further information, contact DARPA Public Affairs (darpapublicaffairsoffice@darpa.mil), Special Assistant for External Relations, Defense Advanced Research Projects Agency, 3701 North Fairfax Drive, Arlington, Virginia, 22203. The J-UCAS web site is http://www.darpa.mil/j-ucas.


November 2004