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Why you need old-fashioned navigation skills

Why you need old-fashioned navigation skills

By Patrick Twohy

 

There’s been talk going around that navigation skills — the kind you’d learn in a Coastal Navigation class or a Celestial Navigation class — are no longer necessary. After all, each of us has a navigation device in our pockets, and most boats are packed with electronics.

Also, you may have heard someone proclaim that traditional navigation is ending now that the U.S. Coast Guard has ceased publishing traditional paper charts.

But that’s all wrong. Just ask the guys who run aground in well-marked channels. 

These are guys (it’s almost always guys!) whose faces are plastered to a screens. That only means they get to observe closely that their screens are lying to them as their boats crunch to an expensive and embarrassing stop.

This happens in Redwood Creek all the time. It also happens elsewhere in San Francisco Bay and on vacation charters far from home. All. The. Time.

But it’s so easy to avoid that fate.

Coastal Navigation Skills never go out or style

The most important navigational skill is one that doesn’t require any equipment. Keep Your Eyes Out of the Boat. That way, you’ll know, by observing aids to navigation on the waterway, that you’re about to cross the line from safe water to water too shallow to navigate in. 

Wouldn’t you get that information from your navigation software? Well, you might, if you know how to use it — which means you have mastered your navigation skills. But many people rely on navigation electronics without understanding what they’re looking at. 

Here are some of the pitfalls you could run into:

  1. Scale. You may see aids to navigation on you screen but assume you have room because you are misinterpreting distances and scales. 
  2. Errors in the software. There’s nothing to guarantee that an aid to navigation, or the depth, or anything out there is exactly what or where your screen says it is. 
  3. Misuse. There’s a famous case where a very well financed international racing team ran their multi-million dollar racing yacht onto a well-known reef because they didn’t see it on their screens. Why was that? Because they had their screen zoomed too far out. 

These are all failures on the part of navigators that could be avoided by simply looking at a printed chart. 

But what about the fact that traditional printed charts are no longer available? The key there is the word “traditional,” which means charts with a traditional layout. Paper charts are absolutely available today — and they’re arguably better than traditional charts because they can be customized to the navigator’s needs. 

But the navigator still needs to look at the chart, know what he or she is looking at, and understand how to proceed appropriately. 

Two basic concepts

Navigation consists of two basic ideas: Know Where You Are, and Know How to Safely Get Where You Want to Go. 

Knowing where you are is the result of the navigator fixing his or her position using any of a list of tools and skills. It often boils down to creating two lines of position and noting where they cross. 

What’s a line of position? Here’s an example: If you take a compass bearing of a known object, you won’t know where you are. But if, say, that object bears 290°,  you know you must be somewhere on the line that is 290° to that object. 

Now, take a bearing of another object. You’ll also be somewhere on that line. Since you must be on both lines, the only place you can conceivably be is where the two lines cross. 

That’s your fix — the Know Where You Are part of navigating.

And taking two compass bearings on known objects is only one of many ways to create that fix using lines of position. You could use a bearing and a distance off a known object; a bearing and a depth contour on your chart; a range line and a bearing; a range line and a depth; a range line and a distance off. And there’s more, some of which are wildly complicated.

You could also create two lines of position using bearings to a single known object taken at different times. You then advance your original line of position the distance and direction you moved until reaching the point where you took your second bearing. 

These skills that every navigator should have are among what’s taught in a Coastal Navigation course. 

You could use your sextant to create lines of position based on positions of stars, planets, the sun or the moon. This celestial navigation is a little more complicated that simply taking a bearing with a compass. But celestial navigation is reliable and requires only accurate time and no other electronics. 

Now that it’s fixed, don’t break it

The Know How to Safely Get Where You Want to Go part of navigating starts with knowing where you are. As with fixing a position, there are numerous tools and methods that to help the navigator know he or she is going the right direction, when to make turns, how to avoid obstacles and dangers, and how to confirm that the vessel is safe.

These skills, too, require the navigator to understand his or her tools and to be prudent in using them. 

None of this is to say that electronic navigational tools have no place on board. They do! And sometimes they’re vital. But they are there to augment and add confirmation to a navigator’s basic skills, not to replace them. 

Also, and this is the sweet finish to a somewhat preachy little article… These skills are a lot of fun. Back in elementary school school, a lot of us liked to draw pictures and play with goofy, slightly complicated toys. This is pretty much the same thing. So let’s have some fun!

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