IO540, you trot out that old WW2 line every time someone on here suggests that pilots should be proficient at conventional nav techniques. As the laws of physics have not changed since the Second World War, then the techniques used for navigating aircraft back then still work just as well. These techniques remain part of the PPL and CPL syllabus and are assessed, so to suggest, as JXK did, that a GPS outage could reasonably cause an accident, and that somebody (presumably other than the pilot) would be to blame, is ridiculous.
It also shouldn't take too much imagination to guess why the MoD might be interested in a GPS jamming capability. Clue: every Tom, Dick and Ali in Iraq, Afghanistan, Libya etc can buy a handheld GPS receiver.
