Definition
A method of navigation in which the pilot determines aircraft position by calculating from a known starting point using known true airspeed, true heading, wind direction and speed, and time elapsed. No external visual or electronic references to the ground are required once the calculations are set up.
Plain English
Working out where you are by starting from a known point and tracking how fast you've been flying, in what direction, for how long, and how the wind has pushed you. It is navigation by calculation rather than by looking at landmarks or instruments tied to ground stations.
Context Anchor
Seen in cross-country planning, navigation logs, pilotage-and-dead-reckoning lessons, and as a backup when GPS or other navigation references are unavailable or unreliable.
Derivation
The phrase 'dead reckoning' is widely thought to come from 'deduced reckoning' — shortened in old maritime logs to 'ded. reckoning' and later read as 'dead.' 'Reckoning' simply means calculating or working something out. So the term means navigating by deduced calculation, which is exactly what pilots do: deducing position from heading, speed, wind, and time.
Why Pilots Care
Provides a reliable backup when instruments fail or in areas without navigation aids, helping maintain situational awareness and reach a safe destination.
Analogy
It is like leaving a town in a car, driving west for one hour at 60 miles per hour, and estimating that you are about 60 miles west of where you started, while also allowing for any detours or delays.
Intuition Check
Dead reckoning navigation is not guessing, and it is not an emergency procedure. It is calculated navigation from a known starting point using direction, speed, time, and wind effect.
Example Sentence 1
On the cross-country flight plan, she used dead reckoning navigation to estimate her arrival time at each checkpoint based on forecast winds.
Example Sentence 2
When the GPS failed, the student reverted to dead reckoning navigation to continue the cross-country leg safely.