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*** Special Notice Regarding LORAN Closure: *** In accordance with the DHS Appropriations Act, the U.S. Coast Guard will terminate the transmission of all U.S. LORAN-C signals effective 2000Z 08 Feb 2010. At that time, the U.S. LORAN-C signal will be unusable and permanently discontinued. This termination does not affect U.S. participation in the Russian American or Canadian LORAN-C chains. U.S. participation in these chains will continue temporarily in accordance with international agreements. You may read more and download pertinent documents via our LORAN-C page.
Local Notice to Mariners
Primary Mission Areas:
Maritime Information:
REPORTED GPS/AIS USER EQUIPMENT PROBLEMS INVOLVING PRN32

On February 27th, 2008 the GPS constellation increased to 32 satellites (PRN 32) thus providing a 5% increase in satellite availability and DOP (dilution of precision) world wide. It has come to our attention that some GPS equipment—particularly old equipment which is non-compliant with the GPS interface standard (IS-GPS-200)—cannot recognize this additional satellite and subsequently are unable to calculate a position (see listing below).

All GPS users are advised to monitor the operation of their GPS equipment and equipment embedded with GPS, e.g. Automatic Identification System (AIS) Equipment and to check with manufacturers for possible fixes/solutions to effected equipment. GPS and/or AIS problems should be reported to the USCG Navigation Center (NAVCEN) at www.navcen.uscg.gov or directly to the USCG Navigation Information Service at 1-703.313.5900.

List of affected equipment: