Ranges are aids to navigation systems employing dual beacons which, when the structures appear to be in line, assist the mariner in maintaining a safe course. The appropriate nautical chart must be consulted when using ranges to determine whether the range marks the centerline of the navigable channel and also to ascertain what section of the range may be safety traversed. Ranges are generally, but not always, lighted, and display rectangular daymarks of various colors.
[CGD 86-031, 52 FR 42640, Nov. 6, 1987; CGD 86-031, 52 FR 46351, Dec. 5, 1987]