Loran navigation system

LOng-RANge radio-based aid to Navigation. The current system (Loran C) consists of a master radio transmitter and two to four secondary transmitters situated within 1,000–2,000 km/600–1,250 mi. Signals from the transmitters are detected by the ship or aircraft's navigation receiver, and slight differences (phase differences) between the master and secondary transmitter signals indicate the position of the receiver. The system is accurate to within 500 m/1,640 ft at a range of 2,000 km/1,250 mi, and covers the North Atlantic and North Pacific oceans, and adjacent areas such as the Mediterranean and the Gulf.

The original Loran system (Loran A) was used to guide bombers on night raids in Europe and North Africa in 1944.