The establishment of minimum luminous range for existing lighthouses in the age of global navigation satellite system by limiting the luminous range within geographical range

Abstract

Long range marine aids to navigation is not required by current marine navigational practice, therefore luminous range of lighthouses should be reduced. The objective of this study is to determine a minimum luminous range for major lighthouses. The minimum luminous ranges is determined by conducting two steps, namely by modifying the existing geographical range formula and determine a strong linear correlation between light intensity and luminous range with the lowest gradient as possible in a linear graph. The application of minimum luminous range would eliminate the loom of light beyond the lighthouse's geographical range, which is not necessary for current navigational practice. This method is applied to seven major lighthouses in Peninsular Malaysia, which resulted minimum luminous range that ranging from 12.2 nm to 14 nm. The existing luminous ranges of these lighthouses are ranging from 18 nm to 25 nm. These new minimum luminous ranges are sufficient for mariners who primarily rely on GNSS, reduce service provider operational cost and may sustain lighthouses operation in the future.