Definition
A ground-based radio navigation system that determines an aircraft's position by measuring the time difference between low-frequency radio signals received from a chain of synchronized transmitter stations. The system has been largely decommissioned in the United States, having been superseded by GPS for civilian aviation use.
Plain English
A navigation system that figured out where an aircraft was by timing how long radio signals took to arrive from several ground stations. Once those timings were compared, the aircraft's position could be plotted on a chart.
Context Anchor
Seen in older navigation equipment discussions, instrument training references, and FAA material that explains non-GPS navigation systems.
Derivation
The name is a straightforward description: it was built to provide navigation over long ranges, well beyond the reach of short-range systems like VOR.
Why Pilots Care
It provided reliable position information beyond the range of VOR or ADF signals, supporting safe flight over water and featureless terrain.
Analogy
LORAN is a little like figuring out where you are by listening for timed signals from several known towers. Because the towers’ locations are known, the timing of the signals can help place the aircraft on a map.
Intuition Check
Do not read “long range navigation” here as a general phrase meaning any navigation over a long trip. In this FAA context, LORAN means a specific radio navigation system that used ground-based transmitting stations.
Example Sentence 1
Before GPS became widespread, pilots flying long overwater routes often relied on LORAN to fix their position.
Example Sentence 2
After tuning the LORAN receiver, the pilot read the displayed latitude and longitude coordinates on the instrument panel.