Your seamanship skills will be tested if you venture any distance offshore and encounter quick moving squalls.
Each body of water presents diverse sea conditions during storms — distance between waves, water depth, wind velocity and strong currents. Hull designs respond differently; outboards can be overtaken by stern waves. Inboards and I/O’s take a greater following sea, but all hull designs are difficult to control in a trough.
Some mariners use the same boat in various waters: inland lakes, Great Lakes and oceans. Waves of six feet on a large lake are treacherous, yet six-foot waves on an ocean passage can be navigated easily. Statistics note most loss of life and vessel damage is the result of operator error, not a boat’s ability to handle rough seas.
Anchoring without adequate scope causes many sinkings.
The anchor takes hold but the scope is too short to allow the boat to float freely. A short scope pulls the bow down allowing oncoming waves to wash over it. NEVER ANCHOR BY THE STERN. When the blunt surface of a boat’s stern is seaward, waves can forcefully break over it. This action can quickly sink a vessel.
When caught in a storm, do the following:
l. Have all passengers put on properly fastened life jackets.
2. Slow your vessel’s speed to maintain control
3. Evenly distribute weight of passengers and equipment in the lowest part of the boat.
Once you gain control, adjust the throttle slowly to a comfortable speed to maintain headway. Determine a course to safety; if it dictates heading into seas too dangerous for your boat, try tacking. Take the seas ahead at a 45-degree angle; first to one side then the other, allowing equal time for each tack thus maintaining the same average heading.
In a following sea, throttle up to control headway and ease back as your bow falls forward off a wave. Throttle up again as the bow rises on the next wave. Use extreme caution to keep the bow from burying in the wave ahead as well as keeping the stern ahead of the wave aft to avoid being overtaken.
When motoring in the trough, adjust your speed to reduce rolling. You may even have to tack, first taking the waves on a 45-degree angle to one side of the bow. You must then turn to take the waves 45 degrees to the opposite quarter. Good seamanship and precise control will be needed as you make your turn, requiring that you nearly stop, then power up as you turn. A burst of power will allow a quicker turn with less time spent in the trough.
The more you know about how your boat responds the smoother the ride. Take it out in adverse conditions (be sure to wear your PFD), and practice to learn how you and your vessel will react if caught in a storm.
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I’ve taken a whole bunch of courses including single motor boat handling, docking, close quarters maneuvering, fire prevention and others. I have also practiced operating boats in a city that has narrow canals with stone tunnels and sharp 90 degree turns.
Now, Boat Handling In Rough Seas is what I really want to go into to be prepared to face big waves and rough seas!!
I agree. I have a Camper-Nicholson 33 and she takes the waves and chop nicely within 20 degrees of the waves. Get a nice gentle rock even at a significant heel with main sail reefed an a working jib on head. Know your boat and keep your safety gear on hand! 🙂 –of course it helps to be on a boat that is built for oceanic races!
I have learned the rule from other Captains and in Coast Guard Aux classes to take a wave at a 45 degree angle.
My boat is a down east design hull which really cuts through the waves in 5 to 6 feet seas. I keep the my bow 10 to 15 degrees into the wave and have a very smooth and controllable ride. If I do the 45 degrees, the boat rocks back and forth and buckle up your seat belt for safety. Know your boat, sometimes general rules do not apply.
Well written article with valuable information. Also be sure the bilge pumps are working and easily accessible for the occasional pluggage