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  • 1 Post By Michael Carr
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Old 10-28-2004
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Avoiding Heavy Weather


Avoiding bad weather is the first line of defense in dealing with it.
For sailors, weather has a strong influence over—even to the point of controlling—our emotions and behavior. I think all sailors know this to be a true statement, even though we often attempt to deny it. A boat's crew is happy and joyful when the sun is shining, the winds and seas are abaft the beam, and navigational fixes are ahead of DRs. On the other hand, we say prayers for a crew who has to beat to windward in breaking seas under gray skies and makes only gradual progress, since there is little joy on this boat.

It takes a fast boat, attention to detail, and humility to avoid bad weather consistently, but vigorous, low-pressure systems usually catch us all if we eventually spend enough time on the water. We can improve our odds of keeping morale up and emotions positive if we avoid fatigue, both mental and physical. Fatigue occurs when we are deprived of rest and sleep, which happens when we are exposed to prolonged heavy-weather sailing. It is not the fatigue itself that is so relevant, it is that fatigue diminishes—often dramatically—a person's ability to think coherently, to make simple decisions, and to engage in rational thought.

So what happens after a bad decision is made? Accidents! Coast Guard statistics show human error, not equipment failure or design, causes 80 percent of marine accidents. With many of these accidents, a dominant ingredient is fatigue. So it's clear that tired sailors make bad decisions and these bad decisions have a high likelihood of contributing to or causing accidents.


Once inside the two-degree-separation zone, mariners can expect conditions to deteriorate rapidly.

For example, if a bad routing decision exposes a vessel to sustained winds of Force 7 (28 to 33 knots) for more than three days, then waves and seas in that region will become dangerous, both in height and propensity to break. Breaking seas regularly occur along the edges of ocean currents (where large temperature gradients exist). A good rule of thumb for avoiding dangerous winds and seas is to minimize the duration of encounter with Force 7, or greater conditions,by allowing two degrees of separation between your vessel and the areas where these conditions exist.

Where did this two-degree separation strategy come from? Well, two degrees, or 120 nautical miles, take into account the error, what I would call "slop," in analyzing and forecasting weather systems. Consider this analogy: you are watching a truck move down a highway and you know its destination. With good information you can track its progress, predicting where this truck will be at a given time. What you probably do not know is what lane this truck will be in at any given time. Maybe it moves into the left lane and passes another vehicle, and then slides back into the center lane. Then it slows down in the right lane before speeding up again. These are microscale movements, which are difficult to track and predict, but they also occur with weather systems.

Our two-degree margin accounts for these microscale movements in weather systems, essentially averaging out the "wobble" or "slop" in their movement. Now, let's say despite your best efforts, you and your crew are caught in the wrong part of the ocean at the wrong time. Winds and seas are hammering you. You have two choices: (1) rig your storm sails and make slow but steady progress away from the weather system and toward your destination or (2) heave-to, wait for conditions to improve, and then resume sailing toward your destination.

For me, the obvious choice is to keep moving. Although, there may be equipment problems or other extenuating circumstances that would support the option of heaving-to, all things being equal, if you can keep moving you should! Why? Mostly for crew morale and the fact that we operate better when making progress toward a destination or goal.


Keeping your vessel on track and making progress will have a positive impact on crew morale.
There is a Chinese proverb that goes: "Everyone pushes a falling wall." What does this have to do with sailing? If you are making progress and your boat is moving, your crew will be thinking positively and will be able to tackle and solve problems. Morale will be high and there will be few crew squabbles and usually fewer equipment problems. On the other hand, try heaving-to for more than a day. You will likely have a mutiny on your hands. Crew members will eventually get on each other's nerves, and with crew below decks, personal space becomes an issue--the head begins smelling, and people start to lose interest and patience. Also fatigue often increases in these situations, which makes people become withdrawn and the Chinese "wall" of group cooperation—normally focused on accomplishing a voyage—begins to lean and fall, and everyone begins pushing.

So my advice is to keep the boat moving, keep people engaged, and demonstrate progress. Imagine this scene, you wake up after a few hours off watch and find you have made significant miles toward your landfall. Is that a good feeling? Compare this to the feeling of waking up to find you have lost the same number of significant miles. I wager the first feeling is one that would make you utter an enthusiastic 'Yes!, while the second scenario would have you saying little, but thinking about taking up camping.


These are conditions you definitely want to avoid, and knowing your vessel's performance characteristics can help you do that.

Traditionally, sailors as a breed relish overcoming difficulty and taking on challenges. Sitting hove-to is too passive. Inactivity breeds depression and frustration. The best solution is to keep a vessel moving, determine the boat's hull speed (1.3 multiplied by the square root of waterline length) and do all you can to maintain that speed.

To keep the boat moving you need to know its performance characteristics, what racers call polars (given this designation because "polars" are typically presented in a polar graph format). At a minimum, you must know your vessel's upwind and downwind velocity made good (VMG) targets, i.e. the best points of sail for going upwind or downwind at a specified wind speed. By knowing these optimal sailing angles to the true wind, you can maximize your vessel's sailing potential, sailing the minimum miles necessary to reach a destination.

What are a few extra miles you say? On an ocean crossing, a few extra miles every day will add up to hundreds of miles over a few weeks. When you hike a mountain or drive to a 7-11 for coffee do you take the shortest route? You bet you do, so why sail more miles than you need to. It is just unnecessary wear and tear on you, your crew, and your boat, and it increases your exposure to inappropriate weather conditions!

Ultimately, this discussion leads to a conclusion about the mixing of weather, boats, and people, which we call seamanship. Seamanship involves massaging, tweaking, and combining these elements to accomplish a voyage. I find myself drawn to a definition of seamanship penned by Captain Lincoln Colcord, a ship captain from Maine. Having spent his life at sea, Captain Colcord defined seamanship as "an attitude and way of life, which face facts, which deal in realities without evasion, which know that the only failure is dishonesty and that error is truth betrayed." That about says it all.

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