John Sheridan

The U.S. Coast Guard and its parent, the Department of Homeland Security, on January 7 announced that U.S. loran-C stations will be progressively shut down between February and October, since everyone now uses GPS for navigation. The banks and the communications industry also moved from loran to the slightly more accurate GPS for split-second transaction timing for our ATMs and our cellphones. 
But timing users have retained their lorans for backup, because GPS isn’t always 100-percent accurate, which is why the FAA doesn’t permit GPS-only IFR in the continental U.S. 
The end of loran-C also worries professionals like Brad Parkinson, “the father of GPS,” who brought the satnav system into the world. Parkinson strongly advocates the need for a GPS backup, and has nominated 
<link ain-and-ainalerts>eLoran for that role. ELoran automatically tracks every loran transmitter within 2,000 miles and, like GPS, selects the best signals for navigation. Computer chip-size units inside a GPS receiver would instantly feed the FMS should GPS be lost, and switch out when it returns. 
GPS is pretty reliable, but handheld jammers can easily overcome its weak signals, along with those of other satnavs such as Europe’s Galileo. One expert described GPS/GNSS jammers as true weapons of mass destruction, should they be used in a coordinated terrorist attack on several major airports when there were 200-foot ceilings up and down the Northeast. Since eLoran is unjammable, the UK and the Europeans are moving ahead with it to back up satnav and to make jamming attacks pointless. 
However, the White House Office of Management and Budget bean counters won’t hear of it. Today, when programs are frequently measured in billions, and a trillion dollars no longer raises eyebrows, the unaffordable loran station network, gobbling up a total of $36 million a year, has got to go.
So is this the end of loran? Not necessarily. Simply mothballing the 20-odd stations would cost about $150 million. Dismantling and removing the stations will cost a few hundred million, but EPA site clean-ups are estimated at well over $1 billion. Smart thinkers therefore propose just mothballing the stations while eLoran is further developed to create a jamming-resistant satnav foundation for NextGen.&nbsp;

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