Common Operating system

DARPA's common operating system, however, is a different animal, enabling the vehicles' autonomy. The software would touch practically everything - command and control (C2), coms management, mission planning, human systems integration and vehicle interactivity, as well as contingency, route and stores management, and sensor, track and mission management. COS is also about reaching out to the global information grid - the Internet in the sky - connecting with the command structure and culling data and applications. Information from networks conceivably could cue aircraft sensors, says Rick Ludwig, Northrop Grumman's X-47 director of business development. "Possibly, if the information is of high enough fidelity, you could actually cue the weapon and release it without a sensor on the aircraft having to find the target," he muses.

J-UCAS researchers envision stealthy, networked UAVs operating all but autonomously over the battlefield. The aircraft would react to changing situations and collaborate among themselves to decide which one of them is best situated to find, image, identify and destroy targets. Key missions include the destruction of networked air defense systems, deep strike, penetrating electronic attack, and intelligence, surveillance and reconnaissance. As missions have grown, so too have the vehicles. The demonstrators being developed for J-UCAS are between an F-16 and an F-117 in size. Boeing's X-45, for example, will grow from 8,000 pounds to 18,000 pounds (3,629 to 8,265 kg) empty weight from the A to the C version. The vehicles will fly at high subsonic speeds at altitudes greater than 40,000 feet with a 1,300-nm combat radius (unrefueled), which is considerably greater than what today's manned fighters can do.

Based on its heritage, Boeing's X-45C reflects the Air Force's interest in stealthy, "first day of the war" missions, while Northrop's X-47B reflects the Navy's need for carrier-based operations. But Northrop is studying emerging Air Force requirements and says it could modify its third demonstrator aircraft into an "X-47B+."

At this size and with these planned missions, the J-UCAS aircraft clearly have to be competitive with manned aircraft to survive into production, acknowledges Michael Francis, DARPA program director. The bar "needs to be raised" on the unmanned side "in the area of mission functionality." That's where COS comes in, as the "de facto integrator," not only within vehicles but between them.

DARPA has a lot riding on COS, which it sees as the government's opportunity to free core software from dependence on air vehicles - and on airframers, the prime contractors who typically control airplanes once they win the competitions to produce them. COS promises architectures that can smoothly incorporate "best of breed," third-party applications as they emerge.

"OSD [Office of the Secretary of Defense] interest in COS is significant because of the leverage it has for interoperability," asserts Francis. "For the first time we're building the hard part of IT [information technology] and segregating it from the platform." Once you do that, he declares, "you can tackle problems separately because you don't have the industrial age component [the airframe] fully intertwined with the information age component from a schedule and cost point." The software would be easier to upgrade, as well.

Manhattan Project?

So DARPA is treating COS a little like the Manhattan Project, the secret nuclear bomb effort in World War II, Francis smiles. The agency set up a consortium, in which the primes - who are building different parts of COS and must share data with each other - are refereed by a third party, Johns Hopkins' Applied Physics Lab, known as the integrator broker. The J-UCAS program, in its current DARPA guise, deliberately avoids a "lead systems integrator," a contractor "daddy rabbit," as Francis terms it, who acts as the overall integrator for the government. The integrator broker, a neutral intermediary, maintains COS configuration control and ensures that new ideas from third parties get a fair hearing.

The J-UCAS program has endured large budget hits and schedule stretches, as a result of pressures on Pentagon spending. But it's still intact. "The fact that we went through this president's budget and came out alive is very telling," says Ludwig. "As a $4- to $5-billion program, we could easily have gone away." He expects a procurement decision around 2010,

Challenges Galore

The challenges surrounding J-UCAS are formidable. How do you get the same effect multiple times and never give the enemy the same look twice, Francis asks. How do you become unpredictable, so you can achieve your desired effects? And what are the implications for the test community if software - the COS - doesn't deliver the same answer twice in a row?

The economic assumptions of the COS development plan are being questioned, as well. For example, what incentives would third-party software developers have to contribute "best of breed" applications if the government shares their source code with others on the program?

At the top of the list is uncertainty as to the program's direction. J-UCAS is moving to the military this fall, just as COS development accelerates. Will the Air Force, designated last year to lead the program, want to scale it back to save time and money? If so, how deep and broad will the software's eventual footprint be?

Despite the challenges, J-UCAS and predecessor programs have made impressive strides. The Boeing X-45A, which has enjoyed a long flight test program, has released inert GPS-guided bombs, flown two-vehicle mock sorties, and demonstrated autonomous attack planning and beyond line of sight control.

The program eyes the following objectives: to build and fly the airplanes to verify basic performance (takeoff, navigation and landing); to demonstrate the feasibility of COS and the ability of the aircraft to perform combat missions; and to generate enough data from flight tests to allow the military to make informed decisions about further development and acquisition.

COS encompasses three software stages: Build 0-infrastructure, Build 1-single ship, and Build 2-multiship, the last of which stretches out till 2009. Boeing has delivered COS data management and discovery services, as well as publish/subscribe components - as part of Build 0. Discovery services allow UAVs to locate applications, such as mission planners and autorouters, on networks. This middleware, some of which derives from Boeing's Future Combat Systems program, provides the infrastructure on which mission application software can run.

Northrop is focusing on the contingency, route, sensor, weapons and enterprise services management, as well as the platform portability, human systems interface and coms aspects of COS. The company has gotten the green light for its Build 1 proposal, but the contract was still pending at press time in August. Other companies, termed technology contributors, also will have opportunities to participate in areas such as the human system interface, autorouters and target cuing.

X-Planes

Boeing and Northrop each will build three, progressively more capable demonstration aircraft - the X-45Cs and X-47Bs, respectively - and begin flying the first of them in 2007. DARPA wants to reach the point where an X-45C ground station can control an X-47B and vice versa. The ideal: "a net centric system of systems where the platforms, sensor and weapons are the peripherals [to the COS]," Francis says. The whole would be much greater than the sum of the parts.

Boeing's X-45As have made more than 60 flights, stretching back to May 2002. In August the company completed a "graduation program" at Edwards AFB, Calif., a mission to preemptively identify, attack and destroy simulated enemy air defenses - ground-based radars and missile launchers. After takeoff, the pair of UAVs used onboard decision making software to select the best flight path within a 30-by-60-mile area of action. Evading an unexpected, pop-up threat, the duo autonomously determined which vehicle held the best position, weapons and fuel to attack the higher-priority target, says Boeing. After the ground pilot authorized the simulated attack, the X-45As "destroyed" the target and returned to base.

Northrop Grumman's Global Hawk UAV pushed autonomy at the platform level, moving to a mouse-driven interface. But J-UCAS pushes autonomy at the system-of-systems level, where multiple aircraft cooperate. To date an operator has controlled two vehicles in flight, four vehicles routinely in simulation, and six vehicles in the lab. J-UCAS envisions flexible, distributed and redundant command and control, Francis says. Responsibilities could be distributed among multiple remote operators. One could handle sensors, another, trajectory management, and yet another, after-action damage assessment. The Air Force and Navy are exploring these issues in simulation. DARPA last year demonstrated X-45 control handoff via satcom between remote operator control stations. Ultimately, the control element could be hosted on airplanes, ships and ground stations.

The X-45A allows the pilot to set the level of autonomy - from the aircraft's asking permission at every juncture to executing an action unless the pilot intervenes within a certain time. Its avionics systems - in come-as-you-are format, taking up one of two weapons bays - included Boeing-built vehicle management and mission management computers, Rockwell Collins ARC-210 UHF coms and BAE Systems Link 16 data link. The A version - essentially a "Spiral 0," concept plane - had a 34-foot (10-m) wing span, and 27-foot (8-m) length. The X-45C, by contrast, boasts a 49-foot (15-m) wing span and a 39-foot (12-m) length.

The X-45A is pretty much "a fly by mouse" aircraft, says Jim Martin, Boeing's director of X-45 system test. The operator console has two screens - a navigation display and air vehicle parameter display. The workload is manageable, however, as the vehicle does its own administrative work, tracking fuel, not-to-exceed speed, maximum G loads and sideslip angles, and the health of its subsystems. It notifies the operator when something has failed. - defense daily