Position line

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 interest ^[2]
• Transit – a line passing through the observer and two other reference points ^[3]
• 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

• Geography portal

• Coordinate line
• Intersection (aeronautics)
• Navigation
• Position circle
• Sight reduction

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
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