What nautical chart danger symbols do you need to know to protect your expensive hull, keel, shaft–and your anchor ground tackle? Discover a little-known sailing navigation technique you can use for safer sailing all season long!
There are more than a dozen specific wreck symbols shown on charts used by mariners throughout the world. All of these are covered in detail later in this chapter, but the three we will discuss first are the foundation–or “brick ‘n mortar”–of all wreck symbols and abbreviations.
Indeed, these three wreck symbols dominate charts in both US and International waters. The first two look like a fishbone and the other resembles a half-submerged hull. I believe the easiest way to find these symbols and abbreviations begins with a fast sketch of your intended route.
Plot your intended sailing track line (also called “course line”). In the illustration above, the dark blue line represents our track line. Next, form a virtual “box” around that line that extends out to port, starboard and ahead of the track. This encloses the track to create a safety zone to help account for leeway or steering errors (red dashed lines in the illustration above).
Base the box size on the chart scale being used and the proximity of dangers in the specific area. For example, on a 1:80,000 scale coastal chart (illustration above), you might sketch a box two miles or more on each side.