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Old 02 November 2010, 12:40   #1
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10 - 15 degress of the Bow

I have read HMS book regarding powerboating in heavy weather. I enjoyed the book untill it got soaked in water and poo (bathing a new baby boy).

I noticed that in several places it refered to heading into a head sea 10 -15 degrees of the bow. I allways take a head sea directly on the nose. I am correct or should I be 10 -15 degree of the bow. I notice that the ride can be harst at times.

Your opinions and why please

TSM
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Old 02 November 2010, 13:21   #2
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It can help by lengthening the distance between waves especially in swell where the sea is smooth but rolling. A boat of a certain length will crash in to the next wave at certain speeds in a certain wave frequency, basically the wrong timing. By adjusting angle you can reduce the frequency of the swell and avoid crashing in to each wave and actually increase speed by getting on to the plane for example.

However if the waves are very large and potentially breaking, going at an angle risks broaching. In that case you need to square up to it in my view to punch through the lip. There are diagrams in the HMS book showing the boat punching through and out the back of the wave. Just ensure your deck drainers are down and you have your eyes closed!

Only imho, i am no expert.
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Old 02 November 2010, 13:26   #3
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I guess that depends on the boat & the state of the sea you are ploughing into.

I've stayed seated & taken the Humber at 20 odd knots straight into stuff I would be "tacking" through while using much throttle movement & wheel turning and having to stand to keep my front teeth intact in the SR4.

On the contrary, I've headed straight into stuff with the SR that my mate in his 5.3 Ribcraft was finding very uncomfortable.

The Dory, however, is more like 45 degrees plus into pretty much anything unless you happen to have a gum shield to hand!
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Old 02 November 2010, 13:40   #4
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Wave punching can be very dangerous if you lose your bottle,or miss time it better to go for the waves shoulder and tack around the big breakers.
Re heading into the waves (long swells) much better to bear away to an angle that increases the wave length and reducing the height giving you that smoother ride .The angle will differ according to the sea conditions bow ballast can help or just dropping the revs to drop the bows for a second or two to allow the bows to slice through the waves (smaller ) rather than climb over it and land with a crash.
AIMHO of course .
Tim
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Old 02 November 2010, 14:07   #5
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When I went from handling our club 5.5m delta to the new 6.8 ribcraft the change in size took me by surprise. Previously I drive up the face of the wave and have to time a momentary throttle back-off well to make the ride comfortable. Just 1.3 meters more boat and weight means you can crash through or squash waves that appeared more scary in the smaller boat.

Your actions are very much dependant on the boat and the conditions. At times, crossing waves at an angle could be a little hairy in the Delta.
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