Air Force mulls on-board commercial backbone

The Air Force is looking to Asynchronous Transfer Mode (ATM) and VMEbus backplane technology to upgrade on-board communications on command and control (C2) aircraft and to eliminate interoperability problems caused among the many nonstandard systems that are currently used.

Central to the new Airborne Command, Control, Communications, Computers and Intelligence (C4I) Architecture concept is the use of open systems, which will allow users "to bring on new technology quickly," said Maj. James Pettigrew, action officer with the Office of the Air Force Deputy Chief of Staff for Command, Control, Communications and Computers. Upgrades are now a "long and cumbersome process," he said.

The C4I concept was first tested last year with low data-rate ATM switches from commercial manufacturer Integrated Systems Technology during the Joint Warrior Interoperability Demonstration, Pettigrew said. Intelligence data was uplinked to the ATM switch aboard a test plane and was passed along military-developed, onboard, dual optical and copper backbones connected to an Ethernet local-area network, he said.

The next step in developing the concept is a full ATM backbone that Mitre Corp., Reston, Va., is putting together for the Speckled Trout, the Air Force's EC-135 testbed aircraft. It will use commercial 2 gigabit/sec ATM switches by Fore Systems Inc. and off-the-shelf VME boards in Mupack COTS VME chassis to interface between the ATM network and legacy aircraft systems, said Bob McKee, group manager for the Embedded Hardware Standards Specialty Group at Mitre.

The Air Force hopes to fly the system by April, Pettigrew said.

The overall idea behind the architecture is seamless "back-end communications," Pettigrew said, referring to the non-flight-critical information systems aboard the aircraft. Typically, these systems in the past have been "stovepiped," or developed independently, without the requirement to talk to each other.

Ultimately, Airborne C4I Architecture proponents would like to see the ATM backbone implemented widely on airborne command and control platforms.

Other programs considering the use of the ATM backbone are the Air Force's Agency-Wide Accounting and Control System, the Navy's TACAMO C2 aircraft and the National Airborne Operations Center, Pettigrew said.

His on-board technology demos are also the "airplane side" of the Pentagon's Battlefield Awareness Data Dissemination program, which is working to "move warrior information around the country in the most efficient way."

"We chose ATM because it's commercially available" and has a good performance level, McKee said.

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Adams is a free-lance writer based in Washington, D.C.