WASHINGTON (States News Service) -- Inspired by the flight patterns of migrating birds, Air Force researchers are developing a new generation of tiny satellites that would be able to fly in close formation.

Satellites of a Feather

Watch the satellites' orbital dance.

"This is a really revolutionary way of doing business," said Alok Das, the chief technologist for the U.S. Air Force Space Vehicles Directorate.

Multi-mission, formation-flying satellites such as these may some day replace today's conventional satellites.

Das compared the development of the satellite clusters to the move from mainframe computers to networked PCs. He said that by combining several smaller satellites, the combined system has greater flexibility and power than a single traditional satellite would.

Some observers, though, don't think that the program may be that innovative.

"This sounds like a solution in search of a problem," said John Pike, the space policy director for the Federation of American Scientists. "All of the things they are claiming about these little guys are generic to all small satellites."

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A closeup of a microsatellite

Maurice Martin, the microsatellite program director, acknowledged that much of the technology used in the new microsatellites has been deployed before, but said that the combination of the technology with the small size of the satellites gives the Air Force more flexibility in designing projects.

He cited a 1996 study that claimed clusters of smaller satellites could accomplish the same goals at a cost that would be about 70-percent lower than that of a traditional satellite system.

Part of the satellites' flexibility comes from the ease with which they can be reconfigured, Das said. Once aloft, the group can be reprogrammed or repositioned easily from a control station on Earth.

"The beauty of the whole thing is that different positions require different formations and with this system, you can just dial a new position in," Das said. "It brings in the upgradability that our computers have today."

If any member of the cluster fails, the other satellites will likely be able to cover the same territory.

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But the migrating birds' contribution is not limited to the clustering. Among the other innovations they inspired is a novel way to maximize the use of fuel aboard the satellites.

As a lead bird gets tired, it moves back within the flock and another bird assumes the lead position. As a result, no bird becomes more tired than the rest.

"This is a really revolutionary way of doing business."
     

So too with the clustered microsatellites. When the cluster's central satellite begins to burn through its fuel, another satellite senses that and takes the lead satellite's place. The result is that the satellites are able to conserve fuel and reduce wear.

Because the smaller satellites would be nearly identical to each other and can be nearly mass-produced, the manufacturing costs would be less.

The current generation of microsatellites is roughly 1 yard (1 meter) in diameter by one-half yard (meter) tall and weighs 220 pounds (100 kilograms), but Das believes that the weight, and possibly the height can eventually be reduced by as much as 20 percent.

Because the vehicles are so small, Das said that many of them could be "stacked like pancakes" into a single rocket, reducing the cost of launching a cluster of satellites.

The Air Force hopes to announce a contractor on the microsatellite project in the next week or two. Das said that microsatellite technology could hold a lot of potential for commercial use.

Martin said that the first launch of the rockets is tentatively scheduled for 2004. The first cluster of three satellites launched will likely be used to demonstrate that the Air Force satellite system works. Later missions will likely be used for surveillance, including monitoring the position of enemy troops.