Tuesday, March 11, 2008


Two day beacons, located some distance apart on a specific true bearing, constitute a "day beacon range." Two lights, similarly located, are a "lighted range." When a ship reaches a position where the two lights or beacons are seen exactly in line, she is "on the range". Ranges are especially valuable for guiding ships along the approaches to or through narrow channels. Most steering through the Panama Canal is done on ranges.

Lights on ranges may show any of the three standard colors, and they may be fixed, flashing, or occulting. Most range lights appear to lose brilliance rapidly as a ship moves away from the range line of bearing.

When steering on a range, it is important to be sure the limit beyond which the range line of bearing cannot be followed safely. This information is available on the chart.