ATC
U.S. Army Interest Suggests eLoran Might Have a Future as GPS Backup
The Army Contracting Command has issued a Request for Information (RFI) covering eLoran receivers for maritime, aviation and/or vehicular platforms.

On Sept. 10, 2001, the DOT’s Volpe Transportation Center in Cambridge, Mass., warned that the very low-powered signals of the global positioning system (GPS) were vulnerable to both unintentional and deliberate jamming. Tests showed that powerful jammers could overcome GPS signals at ranges of 300 to 400 miles from the jamming source. High-powered jammers are not the only threat: several years ago a small half-mile-range $50 “truckers’ special” jammer blocked FAA GPS landing guidance tests for more than a year at Newark Airport before being traced and confiscated. Those jammers are now illegal.