Joining the dots

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US military authorities are struggling with technological, political and financial obstacles as they try to create a modern fighting force

Network-centric warfare in 2020, as envisaged by the US Air Force, is an "air net" with three main layers. The core layer is a constellation of flying surveillance and command and control (C2) platforms. Fighters, bombers, unmanned combat air vehicles (UCAV), airlifters, tankers and individual weapons form a middle layer interconnected by internet-based datalinks. Finally, tactical aircraft, including some coalition machines, are added via the Link 16 protocol in the third layer.

This vision is called ConstellationNet, the air force's component of a larger plan by the US Department of Defense to fully network the battlefield. Much of its success will hinge on new technologies, estimated to cost from $40-50 billion, with many being developed outside the service's control.

At the heart of the C2 constellation - the innermost layer of ConstellationNet - is the future Northrop Grumman E-10A Multi-sensor Command and Control Aircraft (MC2A). Its onboard processing suite, dubbed battle management command and control (BMC2), will serve as the hub of the airborne network, but has been the focus of a year-long cost-cutting push. As a result, the contract to develop the BMC2 suite, expected to be awarded this week, has been stripped to a set of core requirements and refocused on the E-10A's role in pursuing time-sensitive targets such as cruise missiles.

Airborne application

Meanwhile, one of the underlying ConstellationNet technologies is also under intense review, with US air force and Navy officials working on a new set of requirements for an airborne-specific internet protocol (IP)-based waveform. The requirement came after navy and air force aviation staff judged the ground-based wideband networking waveform (WNW), in development for the US Army, may not offer sufficient range and speed for airborne applications.

Linked to the development of ConstellationNet is a bid to harness the networking capability of existing systems. In a series of experiments, the USAF has proved it is possible to download information directly from a fighter's 1553B avionic databus and patch together a reliable airborne C2 net with existing aircraft.

"We really knocked our socks off," says Lorraine Martin, Lockheed Martin vice- president and deputy, joint command, control and communications systems, observing results from two key events - the Joint Expeditionary Force Experiment (JEFX) 2004 and the network-centric capabilities demonstration.

Details of ConstellationNet's three-layer strategy have been outlined by top USAF officials in international forums this year, including a presentation in June by Lt Gen William Hobbins, chief of warfighting integration, who addressed the IQPC Network Centric Warfare Europe 2004 conference in Stockholm.

"I would like us to become much like the internet is today but smarter, a street-smart architecture that anticipates what we, the warfighter, need," says Hobbins. "It learns from me everyday when I log in to the internet and it knows what it is that I am interested in and it feeds me the information from the new domains as they become part of this vast network. We will move this cursor over the target and it is not just about putting the bomb on the target, it is about finding the information and deciding how you would use it."

Hobbins outlined the 15-year ConstellationNet strategy for shifting the service's airborne networks from pairs of aircraft to clusters of space, air and surface-based nodes, each serving as an IP-based receiver, transmitter and router of information. Each node, which could be an aircraft, a weapon or a forward air controller, will be admitted to the network within seconds and "publish" video imagery and masses of data for the benefit of any person or machine with access to the network. Says Hobbins: "The IP network of the future is going to move information in packets from one place to another. And, as long as you have lots of dynamic routers and nodes with which to move it, you can send it out, as the packets of information can go out in any manner and be brought back together with the right keying material - much as a train is formed, with the cars of a train and the front and back being arranged in the right way so that now we can unwrap it and say what it is."

Future air net

The first elements of the ConstellationNet vision are now taking shape, even as the plan to develop the IP-based waveform underpinning the entire network architecture comes under review. By the end of next year, the "air net" of the future will have taken a first small step. The air force will have three aircraft types - the Boeing E-4 Air Force One, Gulfstream C-37 VIP jet and Boeing E-3 AWACS - creating an IP-based, air-to-ground network using the Inmarsat and Iridium satellite constellations. The IP network is provided by Connexion by Boeing, not the future waveform which is still in development, but it will provide the first taste of internet links between the air and ground.

Rather, the air force's primary focus next year for ConstellationNet is making more aircraft compatible with Link 16, the 1990s-era datalink standard for the US military and its allies. It was conceived in military laboratories in the mid-1970s, but truly came of age nearly 20 years later. Now operational on 18 different aircraft types in the US military, it is the airborne network of choice for transmitting voice and data.

At the end of fiscal year 2005, there will be 18 aircraft types on the Link 16 network, although significant connectivity gaps will still exist. Among fighters, the Boeing F-15, F/A-18, AV-8B and Grumman F-14 will be Link 16-compatible, but the Lockheed Martin F-16 will not be in FY05. Instead, some F-16s already have network capability provided by the US Army's Enhanced Position Location Reporting System. The F-16 Block 40/50 also has an improved data modem that can share data between special operations forces and the Boeing RC-135 Rivet Joint.

In FY05, Rockwell B-1 and Northrop Grumman B-2 bombers will have Link 16 capability, but not the Boeing B-52 - an omission that should be addressed by FY09. Also, most unmanned air vehicles are not directly tied to the Link 16 network.

By 2009, the network begins to broaden in significant ways. Says Hobbins: "There are more and more of our platforms becoming Link 16 capable and you can see [by FY09] that we have launched these AEHF [Advanced Extremely High Frequency] satellites that allow us to transmit at four times the rate the Milstar now does. We have also launched the Wideband Gapfiller [satellite], and the MUOS [Mobile User Objective System] satellites, which allow us to exchange amounts of data with surface mobile forces and allows us to use our UAVs on this Wideband Gapfiller."

The addition of satellites provides new channels for ground and surface forces to exchange data with the air fleet, but another significant event will have occurred by 2009 that changes the airborne networking architecture altogether.

"Now we bring on what we call the Joint Tactical Radio System, or JTRS, which gives us an IP waveform," says Hobbins. He showed a chart with a two-layer air net - a circle of Link 16-compatible aircraft and a second cluster of aircraft "that are able to become dynamic routers of information," says Hobbins. "We don't care where the information comes from, all that we care about is that they are able to transfer this information in an IP waveform."

By 2009, if funding is approved, the addition of hundreds of aircraft retrofitted with JTRS radios will create a core network of IP-capable strike, surveillance and command and control aircraft. All told, there will be 17 aircraft types inside the JTRS-based "air net" by 2007. These include the Lockheed Martin/Boeing F/A-22 and the Lockheed Martin F-35 Joint Strike Fighter, still in the latter part of its development. The B-1, B-2, B-52, Fairchild A-10 and F/A-18 also are on board. Surveillance assets have joined the IP-based network, with the Northrop Grumman E-2C, RC-135, Lockheed Martin EP-3E and Northrop Grumman RQ-4A Global Hawk also equipped with JTRS radios. But the heart of this network lies with three "big-pipe aircraft" - the E-3 AWACS, Northrop Grumman E-8 JSTARS and KC-135s equipped with roll-on, roll-off beyond-line-of-sight (ROBE) relay systems.

These "are able to gather in what I call 'the haystack', the big imagery pictures, and narrow down the pixels they will send to the smaller aircraft in the JTRS circle", says Hobbins. The "big pipe" aircraft's higher transmission rate is enabled by the wideband multi-platform Common DataLink.

Satellite upgrades

Meanwhile, 15 US military aircraft types will still lack significant datalink or IP network capability by FY09. That includes the air force's existing fleets of tankers and airlifters. Also excluded are the bulk of the non-army helicopter fleet, including Sikorsky HH-60s, SH-60s, MH-53Es, Bell UH-1Ys and AH-1Zs. In the ConstellationNet vision, there are no plans to bring the Lockheed F-117 stealth fighter on the network.

The JTRS-enabled middle layer of ConstellationNet will continue to expand in the four years after its introduction in FY09. Notably, the Boeing C-17 will receive a JTRS networking capability, allowing it to participate in the IP-based network. The UH-1Y and AH-1Z fleets, meanwhile, will be provided with Link 16 connectivity, but the bulk of the tanker and airlifter fleet will remain off the net.

In FY13, the next revolutionary connectivity leap will be achieved with the arrival of two major satellite communications upgrades. A full constellation of AEHF spacecraft will become the temporary space-based hub of the IP network, providing direct IP-based networking with 11 aircraft types, army ground stations and the DoD Global Information Grid.

AEHF will be able to send more information at faster speeds to C2 aircraft at the core of the IP-based layer that are equipped with the Boeing-developed Family of Advanced Beyond-Line-of-Sight Terminals (FAB-T). By FY13, this will include a new fleet of E-10As with a ground targeting sensor and onboard BMC2 suite.

But AEHF's role at the centre of the constellation will be short-lived, as the satellite constellation is expected to greatly diminish in significance in the seven years after FY13. Indeed, the next major communication system - the Transformational Satellite (TSAT) - will just be beginning to come online in FY13. In that year, current plans call for TSAT to be linked directly to only two aircraft - the USArmy's Lockheed Martin Aerial Common Sensor, which just entered a development phase, and the US Navy's Broad Area Maritime Surveillance UAV, which has been indefinitely postponed. In FY13, TSAT also will be connected to the larger network through links to the AEHF, Advanced Polar satellite system and the Distributed Common Ground Station (DCGS) Block 10.2.

Another key networking improvement planned to arrive by FY13 will provide internet connectivity to thousands of advanced weapons. As nodes in the IP-based layer of the constellation, the weapons will receive updated targeting information while in flight. Imagery and data from the weapon's sensors, in turn, will be transmitted on the network.

Says Hobbins: "We go one step further and talk about weapons datalinks - Small Diameter Bomb [Block 2]; Joint Air to Surface Standoff Missiles (JASSM); Joint Standoff Weapon (JSOW); the Tactical Tomahawk of the future; combined effects munitions. All of these will be on a network-centric environment so that you can have an IP address for a weapon and allow turnover of that weapon to ground forces."

The last elements of the three-layer ConstellationNet strategy are to be in place by 2020. In the air force plan, there is only one aircraft - the navy's Boeing C-40 - that lacks IP connectivity or a datalink by then. The constellation includes several coalition aircraft, including the UK's BAE Systems Nimrod in the core layer and the Panavia Tornado F-3 in the outer layer with Link 16 connectivity.

More significantly, 18 aircraft are now linked to the TSAT system. Only fighters and helicopters appear to be absent from the TSAT-based web of wideband nodes. The TSAT system includes direct links to UAVs, such as the RQ-4A and future UCAV fleet, all three air force bombers, the future Airborne Laser and the bulk of the aircraft involved in the C2 constellation, although a notable absentee will be the navy's Multi-mission Maritime Aircraft.

Link 16 is the last of the current non-internet-based networks to survive in USAF's plan for 2020. Global network connectivity for the airborne network is largely based on a new fleet of satellites capable of communicating at 6,000Gb/s. On the ground are five air operations centres relying on a fibre-optic network transmitting at a rate of 10Gb/s.

"Ideally the TSAT satellite, which is going to give us 6,000Gb/s, when we hit 2020 it enables us to become self-healing and self-forming; it allows us to send any information anywhere in the world," says Hobbins, "form up this air network and be able to communicate beyond line of sight."

STEPHEN TRIMBLE / WASHINGTON DC

ADDITIONAL REPORTING BY PETER LA FRANCHI