Article · Wikipedia archive · Last revised May 31, 2026

Position line

A position line or line of position (LOP) is a line that can be both identified on a chart and translated to the surface of the Earth. The intersection of a minimum of two position lines is a fix that is used in position fixing to identify a navigator's location.

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May 31, 2026
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A position line or line of position (LOP) is a line (or, on the surface of the Earth, a curve) that can be both identified on a chart (nautical chart or aeronautical chart) and translated to the surface of the Earth. The intersection of a minimum of two position lines is a fix that is used in position fixing to identify a navigator's location.1

There are several types of position line:

  • Compass bearing – the angle between a compass point and the line passing through the compass and the point of interest2
  • Transit – a line passing through the observer and two other reference points3
  • Leading line – the line passing through two marks indicating a safe channel
  • Leading lights – the line passing through two beacons indicating a safe channel
  • Sector lights – the lines created by masked colored lights that indicate a safe channel
See also

See also

References

References

  1. "line of position". UNTERM. United Nations. Retrieved 2026-01-24.
  2. U.S. Army, Advanced Map and Aerial Photograph Reading, Headquarters, War Department, Washington, D.C. (17 September 1941), pp. 24-25 [1]
  3. Manley, Pat (2008), Practical Navigation for the Modern Boat Owner (PDF), Wiley Nautical, Chichester: John Wiley & Sons, Ltd, p. 68, ISBN 978-0-470-51613-3, retrieved 2016-05-08