B-52 bombers upgraded with advanced radios.

A new multimode radio system now being installed in the Air Force B-52 bomber enables bomber crews to communicate more easily with Navy ships.

The Air Force will spend $18.5 million to upgrade all 94 B-52H bombers and B-52G trainers. The ability to communicate with the Navy is important, because one of the B-52's missions is to support naval operations, said Larry L. Gray, project engineer for B-52H at DynCorp Technical Services, in Fort Worth, Texas. The company is responsible for assembling and installing the radios. The Air Combat Command is the agency that oversees the program.

The radio is called the AN/ARC-210 multimode set, made by Rockwell Collins Corporation. It covers frequencies between 30-400 Megahertz. Besides the ability to connect with Navy ships, the radio allows the B-52 to communicate with commercial frequencies, such as those used by airports. That is especially important in Europe, where many of the air bases host both civilian and military aircraft. The new ARC-210s will have VHF (very high frequency), UHF (ultra high frequency) and SATCOM (satellite communications) capabilities. More than 40 types of U.S. and allied aircraft, ships and ground platforms are equipped with these radios.

Under the contract, DynCorp also will upgrade the radios with the Demand Assigned Multiple Access (DAMA) capability. The original AN/ARC-210 in the B-52 did not have DAMA, said Gray in an interview. The DAMA is a much-desired feature in a radio, he explained, because it helps manage the bandwidth and makes the network more efficient. There are about 200-250 satellite transponder channels, but more than 14,000 platforms that would like to use those channels. Before DAMA was available, a user had to call into a network control organization and reserve a channel and a time slot. That process was wasteful, because transmissions usually take a few minutes and users would have the channel tied up for a full hour.

"DAMA puts the network control operations under a computer based system and allows multiple people to sign on," Gray said. The computer assigns satellite channels in real time. "It goes from a wideband to a narrow band system, so each of the transponder channels can carry more information," he added. DAMA is a narrowband system.

So far, 61 bombers have received the DAMA upgrade. It will take two more years to complete the entire fleet. Every B-52 that flew sorties in Afghanistan (at least 10 of them were deployed) had to have the DAMA-capable AN/ARC-210. That request came directly from the commander of the operation, Army Gen. Tommy Franks.

There may be other communications upgrades in the future for the B-52, said Gray. Among them is a capability to transmit various forms of data to a weapon system via satellite.

The current SATCOM capability is just a voice terminal, said Gray, "but we are looking at the capability of upgrading it to a data terminal." That would give an operator real-time weather, real-time targeting data and automatic updates of weapon systems in flight.

A data terminal also could help reduce the risk of friendly fire. Fratricide may occur if, for example, the coordinates of a target are misspoken by the ground controller or mistyped into the mission computer by a pilot in the cockpit. "A data terminal would eliminate the possibility of verbal communication error," Gray said.

An Air Force official told National Defense that the B-52 fratricide incident in Afghanistan last year, which killed three U.S. and six Afghan friendly soldiers, is likely to have been caused by human error. At press time, the investigation had not yet been completed. "There can be human error on both ends," he said. "You can give the wrong coordinates or punch in the wrong coordinates." When a pilot receives an eight-digit grid coordinate, it means the target is within 10 meters. Six digits means it's within 100 meters, so missing just one digit can make a huge difference.

A possible fix for that problem, he noted, would be to "databurst coordinates from the ground controller's communications system up to the airplane and into the bomb automatically."