A simple and sensible chart plotting trick.

A spiders web is simply a pre-drawn array of bearing lines drawn on a paper chart from a common point, augmented by useful distance rings centred around the same point (Figure 1).

Figure 2 shows my well-worn chart for the approach to my home port of Christchurch Harbour. All I do is set the Christchurch Harbour entrance buoy as a waypoint on my Chart Plotter, and read off the bearing and distance to run from the electronics as I approach home, and then plot the position on my paper chart.

Many small vessels coming home from the west take the inner channel over Christchurch Ledge. There is a series of rocks just off the shore on the eastern side of Hengistbury Head, however, that has sheared off many a propeller leg. So you can see I have cross-hatched in the danger area on the chart to remind me not to add my props to the tally.