AbstractLORAN‐C IS A HYPERBOLIC system of radionavigation, similar to Loran‐A, which can be used by ships and aircraft for position fixing in all weather, on the sea as well as over land. It operates in the frequency band of 90–110 kilocycles, which was allocated for long‐distance radionavigation systems by the, 1947 International Telecommunications Union Conference (ITU).The first Loran‐C throe‐station chain (triad) was implemented on the United States cast coast in 1957. Since that time much useful information has been learned about the system by employing ships and planes on probing trips into the service area. Results indicate that the system can unquestionably provide high‐accuracy, long‐distance radionavigation service.The United States Coast Guard is now looking toward dual‐frequency capabilities wherein a single Loran station will transmit both Loran‐A and Loran‐C signals. Then, if it appears timely in the future, it would be possible to gradually discontinue the Loran‐A operation with Loran‐C remaining as a single, precision, long‐r