Been pretty quiet on the old GPS gadget front this week — it’s that time of year, though. Fortunately I’ve got a couple of different review units to play with and keep me off the streets. Except in the case of the Magellan 1470, which finally arrived yesterday — that will have be back on the street trying it out. In the meantime, GPS related news continues apace. By now you may have heard about the U.S. Congress’ General Accounting Office (GAO) report that expressed worry about the GPS satellite constellation.

The media picked up on it — my favorite reports came for the U.K. press — and made such a fuss that it prompted the U.S. Air Force to respond. Basically members of the Air Force, which maintain the GPS satellite constellation, have been telling everyone to please just chill the #%@! out; they got this, for reals.

Seriously, as a member of the media — before I blogged, I actually worked as a legitimate journalist for many, many moons — I tend to be by turns both its staunchest defender and its harshest critic. And it went seriously overboard in its coverage of the GAO report. One would have thought that the system was weeks away from imminent failure — one British tabloid termed it as a near systemic meltdown. For those of us that cover GPS, the hubbub has been pretty amusing.

If you haven’t been following this story, let me recap briefly: the first launch of the latest generation of GPS satellites is nearly three years behind schedule because of technical problems. At the same time there have been problems with a fuse that the Air Force’s launch contractor uses, a fuse that separates the satellites from the launch vehicle; this has delayed recent launches as well.

The satellite contractor building this particular generation of satellites, Boeing Co., says that design changes were necessary to this generation of GPS satellites — IIF, in the GPS lingua franca — to ensure the crafts’ reliability.

I should point out, too, that this is, in fact, rocket science. It gets a little complicated sometimes. Anyway, the first IIF launch is slated for November; a previous generation satellite is slated for launch in early 2010.

The GAO report expressed concern that these delays could create gaps in GPS coverage. “If the Air Force does not meet its schedule goals for development of GPS IIIA [the next generation after IIF] satellites, there will be an increased likelihood that in 2010, as old satellites begin to fail, the overall GPS constellation will fall below the number of satellites required to provide the level of GPS service that the U.S. government commits to,” the report stated. You can see the U.S. GAO GPS report summary here, and download the full report.

Now, it takes 24 satellites for GPS to operate globally with the accuracy we all know and have come to love. There are currently 30 healthy satellites on orbit in the constellation, in addition to three older, inactive satellites that could be reactivated if necessary. Assuming that the current launch schedule holds, no less than 11 satellites would have to fail between now and sometime in 2010 to create any gap in coverage.

The likelihood of this happening is infinitesimal, given the reliability of the constellation and ground control system exhibited for the past 30 some years. Even if such an unlikely series of events were to occur, it is not as if location accuracy would degrade all over the world simultaneously; it would be confined to certain regions depending on satellite orbits.

As Air Force Col. Dave Buckman, a spokesman for Air Force Space Command, said via Twitter (!):

No, GPS will not go down. GPS isn’t falling out of the sky. … Going below 24 won’t happen.

The GAO report does make some valid points however, that the Air Force and the gub’mint need to address if the reliability and accuracy for which GPS has become known is going to continue indefinitely. The big one in my humble opinion, as someone who used to write about this stuff, as stated in the report:

Of particular concern is leadership for GPS acquisition, as GAO and other studies have found the lack of a single point of authority for space programs and frequent turnover in program managers have hampered requirements setting, funding stability, and resource allocation.

But such is the nature of the beast. GPS started out as a purely military program, but it has morphed into quite a different animal. Until the 1990s and the Gulf War, there were even those in the military that questioned the need and expense for GPS; there have been shortsighted bigwigs that tried to put the axe to the program.

Since then, while its efficacy can’t be denied inside the military now, the growth of its use in the civilian sphere has been exponential, and this is what lies behind some of the problems the GAO report highlights — even since the 1990s, for example, the military has had to fight hard for funding from Congress for GPS, even as civilian government oversight of the program grew.

In that sense, the report and resulting media hullabaloo may be a good thing, in the long term.

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