LORAN
Videos
LORAN was a hyperbolic radio navigation system developed in the United States during World War II. It was similar to the UK's Gee system, but operated at lower frequencies in order to provide an impro
The AN/APN-4 was an airborne LORAN receiver used into the 1960s. It was built in two parts to match the UK's Gee system, and could be swapped with Gee in a few minutes.
AN/APN-4 LORAN in RCAF Canso (PBY) aircraft
R-65/APN-9 in a B-17G aircraft
The signal from a single LORAN transmitter will be received several times from several directions. This image shows the weak groundwave arriving first, then signals after one and two hops off the ionosphere's E layer, and finally one and two hops off the F layer. Operator skill was needed to tell these apart.
Loran-C
Videos
Loran-C is a hyperbolic radio navigation system that allows a receiver to determine its position by listening to low frequency radio signals that are transmitted by fixed land-based radio beacons. Lor
LORAN
…and accuracy of hundreds of feet. When the Air Force turned their attention to inertial navigation systems, the Navy took over Cyclan and renamed it Loran-C. The United States Coast Guard took over operations of both LORAN systems in 1958. Despite the dramatically improved performance of Loran-C, LORAN, now…
A Loran-C receiver for use on merchant ships
LORAN Station Malone, Malone, Florida Great Lakes chain (GRI 8970)/Southeast U.S. chain (GRI 7980)
Cesium atomic clocks
LORAN transmitter bank