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Delay in launching new GPS satellites could decrease accuracy significantly

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Slight chance GPS satellite delays could upset service


GPS satellites originally scheduled to head skyward in 2006 are awaiting launch in 2010, a delay that means pieces of the high-altitude network could start falling out of service, fouling everything from the accuracy of U.S. bombs to the reliability of your neighborhood cash machine.


By Scott Canon


McClatchy Newspapers


KANSAS CITY, Mo. — The oldest of America's navigation satellites soared into the heavens just as the Mazda Miata first took to the road on Earth.


Like a rusty 1989 sports car, there may be more life left in those artificial moons. And like that old Mazda, they could give out any time.


GPS satellites originally scheduled to head skyward in 2006 in a $7 billion-plus program aimed at keeping the system going are awaiting launch in 2010.


The delay means pieces of the high-altitude network could start falling out of service as early as next year. Such decay in the system could foul everything from the accuracy of U.S. bombs to the reliability of your neighborhood ATMs.


"It's ubiquitous. It's like electricity," said Cristina Chaplain, of the Government Accountability Office (GAO). "Now we're not launching new satellites as quickly as they're expected to die."


Yet, it would take Chicken Little to predict that the wonders of the global positioning system are about to tumble into collapse.


The Air Force has 30 navigation satellites stationed above the planet. Two dozen are needed for tens of millions of military and civilian uses. Some of the oldest were rocketed into orbit 20 years ago. The newest went up last month.


Some of the extras can be shifted to replace satellites that fail.


Yet, a recent GAO report said, "There is a high risk that the Air Force will not meet its schedule for GPS." Next year, the GAO said, there's a 5 percent chance that fewer than 24 will be working. In 2011 and 2012, that jumps to 20 percent.


If another two-year delay is added to the launch of newer replacement satellites — something the GAO sees as possible — the probability of having fewer than two dozen working satellites from 2017 through 2019 shoots up to 90 percent.


GAO criticized the Air Force for delegating too much of the decision-making during the past several years to contractors and not making sure that work was progressing as quickly and as efficiently as needed.


The report cited one critical test in 2008 on new satellites to check their space-worthiness. That created another delay, part of a cost overrun that more than doubled the expense of one facet of the program to $1.6 billion.




Work has been complicated, Chaplain said, by contracts for different phases of the GPS program shifting between Boeing and Lockheed while new functions continually were added to the satellites.


"There was always that sense that we lost the recipe," Chaplain said. "Then you not only lost the recipe, but it was like you were making a whole new dish."


Delays in the program also add to the perception that the Air Force has trouble pulling off big space projects.


A space-based infrared system needed to track missiles and serve as an early-warning system is years behind schedule and 245 percent, or $7.8 billion, over budget. Defense Secretary Robert Gates recently killed the Air Force's transformational communications satellites system — that would have given the military laser-based mobile data hookups — after it ran into delays and budget problems.


As for GPS, the Air Force said users of the system had nothing to worry about.


"I have high confidence we will continue to sustain at least the 24 satellites required to maintain our current performance standard," said Gen. C. Robert Kehler, commander of Air Force Space Command.


Even with a reduced force of satellites, GPS would work for a while. But not as well.


Your Garmin or Tom Tom navigation device points you in the right direction by calculating signals from at least three satellites, each more than 12,000 miles away. By measuring the time it takes for signals to travel from each satellite to your location, relatively simple geometry identifies where you are.


More often, a GPS device captures signals from four or more satellites and its accuracy improves. If the fleet drops to, say, 18 satellites, your navigator might have to settle for directions accurate within a block rather than down to 10 feet.


The industry is not panicked.


"We don't think there's a real reason to fear a significant outage," said Ted Gartner, a spokesman for Olathe, Kan.-based Garmin. "It's just too important to the government."


Copyright © 2009 The Seattle Times Company

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A similar article came out a week or two ago in the Tacoma News Tribune from an AP story. It was your typical over-reaction scary headline and intro, with worst case scenario suppositions trhoughout, but at the end of the article you find out that there is already excess satellite coverage and that there is no real danger of any interruption. As the Garmin rep states at the end of the Seattle Times article, it's just too important to the government for there to be any significant outage.


For some strange reason, after reading articles like this I always just want to slap the reporter upside their head a little. Weird.

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