Surveyors to get long lunch in 2011 or 2012
Engadget has a post on some research that suggests that there will be an almost 90 percent loss of GPS signals for a number of hours at the height of the next solar flare cycle in 2011-2012. While surveyors may be looking forward to a long lunch or afternoon off, you may want to avoid traveling by sea or plane that day just in case :-).
Solar flares to disrupt GPS for several hours in 2011 or 2012 – Engadget