During a recent on-water technology test, I pressed a button, sat back and let the boat dock itself. The boat in question not only had automatic-docking technology with joystick controls, it had a full radar system, AIS, autopilot, collision alarms, charting software displaying our position in fine detail and cameras showing every angle of the boat on flush-mounted touchscreen displays.
The technology at our fingertips makes the job of captaining a boat easier and safer than it’s ever been. That said, there are still plenty of things that have nothing to do with electronics that you should know. Here’s a quick rundown of seamanship skills that don’t need AC/DC power, just brain power.
Reading Paper Charts
Today’s charting software lets you know exactly where you are on the water at all times, as well as your course heading and your deviation. You should still carry paper charts on board as a backup and, at the very least, know how to read the symbols and terminology on both a paper and electronic chart. The easiest way to learn it all is to head to NOAA’s Symbol Legend for US Nautical Charts, known as Chart No. 1, at nauticalcharts.noaa.gov/publications/us-chart-1.html. Download the file and get to know the difference between a green parallelogram and a green rectangle symbol.
Using a Compass
A dash-mounted compass used to be a standard feature aboard most boats. If you don’t have one, get one. You’ll need it to keep the proper heading on a paper chart. Every chart will have a compass rose, with an outer ring indicating true north, and an inner circle showing magnetic north, the direction to the magnetic pole. On the chart, magnetic north will have a smaller arrow pointing slightly off-kilter to the star that indicates true north. Your boat’s compass will follow magnetic north, allowing you to set a bearing based on 360 degrees—with 0 being north, 90 being east, 180 being south and 270 being west. When out of sight of land or any navigation markers, or when its dark or foggy, using the compass bearing helps ensure you’re heading in the right direction.
Rule of Thirds
In the old days of analog fuel gauges, the needle swinging between empty and full was always notoriously unreliable. For this reason, it was very important to know your engine’s fuel-burn rate in both miles per gallon and gallons per hour. Using these numbers, you could estimate how much fuel you burned on a given cruise and know how much fuel you needed for the rest of the day and to get home. Today’s digital displays accurately show how much fuel you have left in the tank and may even show your total range based on your engine’s rpm as you cruise. It’s still good practice to live by the rule of thirds: use a third of your tank to get where you’re going, keep a third in reserve to get home, and save the last third for variables and emergencies. Of note, we derived all our testing range numbers based on 90 percent of a fuel tank’s capacity, and you should do the same. This accounts for the last gallons in the tank that may fall below both the sending unit and the pickup tube.
Read Next: The Importance of Having a Co-Captain
Rule of 60
When using paper charts, this is a good one to know. The 60-to-1 rule is a principle used in navigation, both in aviation and in boating, stating that after traveling 60 nautical miles, a 1-degree error in your course will result in your being 1 nautical mile off track. It is a mathematical rule of thumb used to estimate angles for determining track and heading changes. For example, if you are 1 mile off course after boating for 10 miles, you are 6 degrees off course.
This rule is a technique that supports the fundamental responsibilities of safe vessel operation outlined in the Navigation Rules, or COLREGS. These rules, which include maintaining a proper lookout, proceeding at a safe speed, and determining the risk of collision, are vital to preventing accidents. The rule is particularly useful for correcting a course due to factors such as wind or current.
