Quote:
Originally Posted by genieskip
Two points.
You don't have to be dropped off a wave to have the steering damaged. The force of the wind under the kinds of conditions discussed in this thread, combined with the slacking of the parachute rode because of an out-of-synch moment, are enough to make a boat "hit reverse" with enough speed to damage the steering.
The problem with the JSD is that to be truly effective it should be secured to something equivalent to chain plates on each quarter with metal hardware. I haven't figured this one out yet. After sewing up some 120 GD little cones and feeling like I did time in a sweatshop I am scratching my head trying to work this out without adding hardware that would change the look of the boat.
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Genie, Joms, Val, etc. - okay, bear with me here. One thing I may not be getting right in all this is the
direction of force with breaking waves. How about some pretzel logic?
To try keep this straight - let's have the boat be bow-on for this example...
I understand that when the boat comes onto the face of a wave (as pointed out earlier) it moves in the same direction of that wave. In my mind, this is force 1. And I can totally understand that if the boat is bow-on and gets taken by force 1 strongly enough with a steep enough face, the rudder blows because you do a reverse surf. The direction of the greatest force at that point is from stern to bow because the boat is moving backwards.
We do know that waves can be pretty damn steep and pretty damn high - and as long as they don't break, a boat can ride them relatively safely as long as we avoid the force 1 scenario above. And we know that an anchoring/drogue device deals with this particular force very well. Right?
But here's where it seems to me that things get tricky...
In the event of a breaker atop that wave, you now have force 2 - which is far more powerful than 1. And it's this second force that typically dooms a boat because it's so violent. Correct?
Okay - now
if the boat is somewhat stationary because of an anchoring/drogue device and that force 2 hits the boat at 20 knots, with white water smacking into, around, and past it...this particular force is actually moving from bow to stern (because we are essentially held in place bow-to the wave)...right? And this second force is far greater than force 1 - especially if the boat is indeed being held in virtually the same position by the device.
If this is accurate, this is why it seemed to me that the rudder, etc. would suffer less with a breaking wave strike bow-on than it would stern-on because if the device was actually doing it's job keeping the boat in place bow-on to the wave, this huge blast of water would flow past the rudder in the direction it's intended to. If you were stern-to, this blast would actually do what we're trying to avoid with force 1 above, but with far more damaging results because of the greater force of 2.
It seems like when you use any anchor/drogue device that does it's job and you have breakers, you're actually dealing with
TWO forces that go in opposite directions. If so, then it comes down to which force is more dangerous. That's the one you have to plan for.
Does this make any sense?