Definition
The slant-range distance in nautical miles displayed by the aircraft's Distance Measuring Equipment, indicating how far the aircraft is from the selected DME ground station.
Plain English
The number shown on the cockpit instrument that tells you how far you are from a particular ground station, measured in nautical miles.
Context Anchor
Seen during instrument flying when a holding pattern is based on DME distances instead of only timing.
Derivation
DME stands for Distance Measuring Equipment. 'Readout' simply means the value the instrument displays — what you read out of it. Together: the distance figure shown on the DME indicator.
Why Pilots Care
Provides the exact distance needed to identify holding fixes and ensure proper pattern entry and timing.
Grounding Statement
If the DME display says 12.0, the aircraft is about 12 nautical miles in a straight line from the selected DME station.
Intuition Check
Do not assume the DME readout is distance along the ground track or time remaining. It is the displayed straight-line distance from the selected DME station.
Example Sentence 1
The controller cleared the aircraft to hold southwest of the VOR on the 220° radial, with 10 NM legs flown by the DME readout.
Example Sentence 2
With the DME readout showing 5.3 nautical miles, the crew began the turn to the inbound leg.