Sumner Line

Sumner line

[′səm·nər ‚līn] (navigation) A line of position established by the Sumner method. Any celestial line of position (deprecated usage).

Sumner Line

 

a celestial line of position established by the Sumner method. Sumner lines are straight lines of equal altitude and are widely used in navigation to determine the position of a ship or airplane through observations of the altitudes of celestial bodies.