Definition
Radio signals transmitted between an aircraft and a ground station (or satellite) that are used to measure the distance between them. The system measures the time it takes for a signal to travel out and back, then converts that time into a distance.
Plain English
Signals used to figure out how far the aircraft is from a known point, by timing how long the signal takes to make the round trip.
Context Anchor
Seen in GPS navigation discussions, especially when explaining how a GPS receiver determines an aircraft’s position.
Derivation
From 'range,' meaning distance to a target — a usage that comes from gunnery and surveying, where 'finding the range' meant working out how far away something was. In aviation, ranging signals do the same job: they find the range to a navigation station.
Why Pilots Care
Gives pilots accurate distance readouts needed for timing, position awareness, and safe navigation during instrument approaches and en route flight.
Intuition Check
Ranging does not mean looking around or aiming the signal. Here, it means measuring distance from the GPS receiver to a satellite.
Example Sentence 1
The DME uses ranging signals to display how many nautical miles remain to the station.
Example Sentence 2
Ranging signals allowed the crew to know their exact position along the approach path.