After a brief overview of Loran-C system operation and
performance, the present situation of
the system in Europe is described. Loran-C is now in operation under the
NELS agreement
in north-western Europe in newly established chain configurations with
old and new
transmitter positions. Parallel to Loran-C the Russian equivalent, Chayka,
is also operating,
with three chains in Europe. There is an agreement between Norway and Russia
concerning
cooperation and possibly joint chain operations between the two system
providers in the
north; similar agreements in the Baltic and Mediterranean/Black Sea
areas are being worked
on. The situation around the Iberian peninsula has not yet been clarified.
Being the only
long/medium-range terrestrial system in Europe in the 2000+ time frame,
Loran-C could be
seen as a supplement to satellite systems. Due to the good penetration
properties of its
low-frequency signals, it can be used in many circumstances where satellite
systems fail because
of limited satellite visibility. Integration of Loran-C and
(differential) satellite receivers, where
Loran-C is calibrated by the satellite system as long as there
are enough visible satellites, could
in fact give the best of both worlds. For this reason, Loran-C is being
considered in the
perspective of a future international, civil satellite navigation system,
initiated in Europe.