ANALYSIS OF LINES OF POSITION USED IN COASTAL NAVIGATION

Abstract

Coastal navigation requires continuous and accurate determination of a vessel’s position to ensure safety, efficiency, and adherence to the planned voyage. This thesis presents a systematic analysis of the Lines of Position (LOPs) used in coastal navigation, examining their principles, classifications, methods of application, and inherent limitations. The study addresses both bearing-based and non-bearing-based techniques, highlighting their continued relevance in navigational practice, particularly in situations where electronic systems are degraded or unavailable. Core concepts including bearings, ranges, cross bearings, running fixes, horizontal angles, transit lines, distance arcs, soundings, and lines of equal depth are discussed with emphasis on procedural accuracy and reliability. The research follows a structured methodological approach, beginning with a theoretical foundation of LOPs and progressing to detailed chart-work applications. Navigational instruments such as the compass, sextant, parallel rulers, dividers, station pointer, and transparent paper are evaluated in relation to their effectiveness in position fixing. Special attention is given to object selection, angle optimization, time management, and the correction of compass and observational errors, all of which significantly influence fix accuracy. General and systematic errors commonly encountered in coastal navigation are analyzed to enhance situational awareness and decision-making. A practical case study constitutes the core of the thesis, demonstrating the application of multiple LOP methods along a defined coastal route using real chart data and vessel particulars. The results confirm that traditional position-fixing techniques remain essential navigational skills. This thesis provides a comprehensive academic and practical reference work.