The oceans and waterways can be unpredictable and challenging environments. That’s why, for most boaters, being in the water is exciting and the source of their joy and leisure time activities. To keep the fun in boating while increasing the safety, all sailors, from experienced to amateurs, should always have a couple of key skills up their sleeve. Here are 3 skills every boating lover should learn and keep on hand.
1. Dead Reckoning - Navigating
Before the modern navigational instruments such as the GPS and ECDIS, positions at sea were mostly determined through celestial and terrestrial methods. In the past, sailors used speed measured in knots, distance in nautical miles and time measured in minutes. They could plot their present position or project a future one from a previously known spot or fix. In other words, they just needed a paper chart and a compass in order to find their way home. Accuracy depended on the frequency of fixes and compensation for wind and current. Not a big deal!
Nowadays, learning this technique could save the day. It could bring you home safely in the event your chart plotter or GPS do not work, or simply increase the fun factor on your way back to port.
2. Docklines - Tying Up
Tying up at a dock is one of those elegant techniques every boater is proud to learn, but what about the docklines? Docklines limit a boat's movement, ensuring its safety when it is on a stop. The key is to be able to recognize how many docklines will limit your boat's motion, and decide on the most effective combination.
Spring lines limit how much the boat can move forward or backward. Breast lines limit how much the boat can move closer or away from the dock. Bow lines and stern lines may do both. The following image (figure A) shows all the possible docklines you could use. However, when tying up, the goal is to use only the ones needed to secure the boat.
For a short stop, you should be able to tie up with just three lines (Figure B). The best combination of docklines is typically at least one spring line, plus a bow line and a stern line.
For heavier weather and longer stays, add a second spring line in the opposite direction of the first, as shown in the next image. Don’t forget to adjust the line lengths to allow for tidal rise and fall.
When tying up in a slip (Figure C), try to avoid breast lines. Instead, run your bow lines forward a bit and cross your stern lines. In this case, four docklines are the optimum: two bow lines, and two stern lines. As for leaving room for the water to move up and down, the same caveats still apply. This way, all the lines are working together to limit motion forward, and side to side.
3. Shallow Water - Reading
Everyone loves a beautiful sunny day, and the set of blues the sea can dress itself up with. But be careful, don’t get distracted by the refreshing sea spray and beautiful blue water. Instead, use the water colors to assess the water you are in, looking for color-change and contrast too. Remember, colors are key to reading the water!
• Blue, green or turquoise water: bright colors normally indicate that the depth is probably acceptable for most pleasure boats to navigate.
• If the colors are very pale, the water could be too shallow and should be avoided.
• Brown water surrounded by blues or dark green is probably mud, sand or shell shoals.
• White water indicates a very shallow sand bank.
• Yellow water indicates a shallow bank, either of sand, marl (rocky hard sand) or rock.
• Light brown or yellowish-brown water indicates a shallow rocky bar.
• Darker or yellowish-brown, with some green or blue over it, also indicates a rocky bar but one that is deeper under the surface.
• Coral attaches only to rock, not sand. If the water is bright blue but you can see yellow, brown or other light colors just beneath the surface, there may be a very tall coral reef close to the surface.
Keep always in mind that there are several light situations that affect visibility, so it is a great idea to scan the chart plotter regularly to identify potential hazards well in advance.
"Fair Winds and Following Seas."
Bhattacharjee, S. (18 de May de 2017). What is Dead Reckoning Navigation Technique at Sea? Obtenido de Marine Insight : http://www.marineinsight.com/marine-navigation/what-is-dead-reckoning-navigation-technique-at-sea/
Murphy, T. (15 de July de 2015). Tying Up At The Dock. Obtenido de BoatUS: http://www.boatus.com/magazine/2015/june/tying-up-at-the-dock.asp
Soundings . (29 de April de 2005). Sea Savvy - Colors Are Key To Reading The Water. Obtenido de Soundings: https://www.soundingsonline.com/news/sea-savvy-colors-are-key-to-reading-the-water