NELS Status Operational and political status

摘要

The North-west Loran-C system (NELS) has been in muddy waters since the early beginning in 1995. Loran-C in Europe was until 1995 operated by USCG, primarily for military purposes. US decided to continue to operate only Loran-C transmitters located on US territory and the European transmitters were offered to the European host nations. NELS was established and 6 European nations (Denmark, France, Germany, Ireland, The Netherlands and Norway) started operating Loran-C in Europe for civilian purposes in January 1995. NELS decided to establish TOE control and all USCG transmitters taken over by NELS were upgraded (TOE monitors at site as opposed to SAM monitors in the field) and additional infrastructure were installed. I addition to the former USCG stations, the two French stations, Lessay and Soustons (TOE stations) were included, two new stations along the Norwegian coastline were established and a new station in Ireland was planned. Because of this new configuration of station and chains - new GRIs (Group Repetition Intervals) had to be established. These were done successfully, except for the fact that several users decided not to upgrade their Loran-C receiver and switched instead to GPS or Decca. The Control Centre in Brest (CCB) was totally rebuilt and reconfigured to allow for TOE control of NELS as apposed to TOE control of the two French stations. In the mean time, the Control Centre in Bo was used as the NELS control centre. Finally in January 2000, CCB was declared operational and the NELS infrastructure was almost complete. Only the Irish mast is still well stored in France and the transmitter stored by Megapulse, US waiting for a legal permission from Ireland to erect the mast.