Bad news: further evidence that the worldwide GPS system, which is run by the US government and on which everything from airline navigation to iPhone mapping apps relies, is at risk of "browning out." Earlier mention of the problem, back in May, here, based on this government report. Update this month, from Avionics magazine, here. Talk about your deteriorating critical infrastructure! Headline below gives you the gist.

"Fixing GPS

"Almost half of the current constellation of GPS satellites are at or approaching 'single thread' operation, where a critical system failure could render a satellite inoperative. What are the options for replacing GPS satellites?"

Now, the better news. Assuming that the GPS network gets tuned up in time, Scott McCartney, of the WSJ, explains some of the potential for better, more efficient, and safer airline navigation -- including over the vast oceanic "big blue data void" into which Air France 447 disappeared. The "NextGen" navigation systems McCartney describes have their strong supporters and critics, when it comes to specific configurations and timetables for the program. But a shift to some version of the new system is as inevitable, and McCartney explains clearly what the benefits can be.

This article available online at:

http://www.theatlantic.com/technology/archive/2009/10/bad-news-good-news-on-the-air-traffic-beat/28889/