What Is DME? Definition & Meaning in Aviation
DME (distance measuring equipment) is a ground station that tells an aircraft how far it is from the station.
In plain language
The aircraft sends a radio pulse and the station replies; the delay gives the distance. DME is often paired with a VOR to give both bearing and distance.
Example
A pilot can fly an approach that uses DME distance to step down to the runway.
Why it matters
DME gives distance information that helps pilots fly precise approaches and step-down procedures, especially where other aids are limited. It is a quiet but important navigation tool.