Monday, July 2, 2012

Heavy Weather Sailing


Heavy Weather Sailing - - Some Basics
Wind Force Matrix





Wind Speed
Beaufort
~Boat Speed
Pressure
300 sq ft
Water
Wind
Knots
Scale
Close Hauled
Per Sq Ft
Sail Area
State
Terminology
1 - 3
1
Steerageway
.003 - .03
9 lbs
Ripples
Light Airs
4 - 6
2
1 -3 knots
.05 - .12
36 lbs
Many Ripples
Light Breeze
7 - 10
3
4 - 5 knots
.16 - .33
99 lbs
Waves Begin
Gentle Breeze
11 - 16
4
6 - 7 knots
.40 - .85
353 lbs
Long Waves
Moderate Breeze
17 - 21
5
First Reef
.96 - 1.4
420 lbs
Whitecaps
Fresh Breeze
22 -27
6
Second Reef
1.6 - 2.4
720 lbs
Many Whitecaps
Strong Breeze
28 - 33
7
Heave To
2.6 - 3.6
1080 lbs
High Sea Running
Moderate Gale

“Heavy weather” is generally understood to be wind and water conditions where the boat becomes difficult to handle.  The boat might be heeling excessively (washing the windows); or the person on the helm might not be able to steer a given course (lots of pitching and yawing); or the boat does unexpected maneuvers (unexpected violent jibes or uncontrolled 360 degree spins).  Being inexperienced or unprepared for heavy weather is frightening at best and downright dangerous at worst. 

Take a look at the “Wind Force Matrix”.  Notice that up to Beaufort Scale of 3 or 4 everything is fine.  Sailing is wonderful - - - just what everyone loves about sailing.  Sometime during force 4 – and certainly into force 5 – the wind force becomes more than many sailors are comfortable with - - - let alone, happy about.  Notice the wind pressure equivalent on a 300 sq ft sail.  That pressure is being felt by the rig, sails, sheets and halyards.  Imagine trying to hold 350 to 420 lbs - - - let alone trying to control that force.

Interestingly, on inland lakes where the wind has insufficient fetch to develop an ocean wave pattern, one or even two forces should be added.  You might experience Force 3 wave action while experiencing Force 5 wind pressure.  This is particularly evident on large inland lakes like Pend Oreille and Coeur d’Alene in Northern Idaho.  If a Force 5 wind is blowing out of the southwest at Lake Pend Oreille for instance; there is very little wave action near Bayview at the south end of the lake.  Prudent skippers still reef their mainsails and/or shift down to smaller jib sails to decrease healing and keep their boats under control.  At the same time, twenty five miles north up the lake near Pearl Is. and Cottage Is. there will be a true ocean sea running.  The lake will be covered with many whitecaps and the waves will be quite large.

Experienced skippers need to keep many things in mind as the wind freshens and conditions begin to approach “heavy weather” so that the boat and its crew arrive at their destination safe and sound.  Some of these considerations are:
Appropriate clothing;
Safety harnesses, Life jackets, and Jack lines;
Rigging knives and other tools;
Health – including hypothermia, potential injury, and hypothermia;
Preparing the boat for heavy weather conditions;
Reefing the mainsail;
Rigging and setting a storm jib.


Here’s a photo of a twenty-eight-footer in heavy winds on Lake Pend Oreille during an August storm in 2009.  Even though the wind was blowing 25 to 30 knots and gusting as high as 40, note that the waves are not all that large.  This skipper though has reefed the mainsail and has a smaller working jib up.

What is “appropriate clothing” for heavy weather conditions?  Clearly, it is important to avoid hypothermia.  And, since wet clothing and strong winds quickly sap your body heat, waterproof clothing is a must.  This waterproof clothing is often called “foul weather gear” or “foul weather clothing”…… “foulies” for short.  At a minimum, your foul weather clothing should include:  waterproof pants, waterproof jacket, sea boots, and a sou’wester hat.  Buy your pants, jacket and boots larger than your “normal” size.  You will probably have multiple layers of clothing on under the pants and jacket; and you might want to wear heavier than normal socks (even two pairs of socks).  These extra layers take up space and make a “normal” size tight and quite uncomfortable.  The layers under the foul weather jacket and pants might include: long underware bottoms and top; fleece pants and sweater; wool or fleece jacket; snow skiing socks; and a wool or fleece stocking cap (watch cap).  To take up room in the oversized sea boots, buy a pair of felt liners.  The sou’wester (Gorton fisherman) hat is a must!!  The long back protects the back of your neck from water, and the front “bill” can be turned up or down depending on rain or spray hitting your face.  An unusual piece of foul weather clothing that some of us now have aboard is alpine ski goggles.  With wind-blown spray all over the place, these ski goggles protect your eyes and the lens can easily be wiped with a finger to provide good visibility.  Additionally, alpine ski goggles often come with a “no fog” coating on the inside of the lens that really works.  Two final thoughts about foul weather clothing:  buy your foul weather pants in a “bib overall” style that has suspenders.  These afford more protection, are warmer, and are just the right “fashion” to wear if you are the cook in the galley while under weigh.  And, don’t be a “tight-wad” when buying your foul weather gear.  I can speak from personal experience that it is a terrible experience to have a seam open up on your foul weather jacket in a heavy rain storm.  Can you spell WET, WET, WET???  I can……


Here we are - - all suited up in our “foulies”……

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