A-cat Kipping?
I was sailing my (LR?) A-Class last week in moderate sea state, maybe 2', moderate breeze, around 10-13kts, enough wave height to get the boat tommyhawking a bit, noticed that because of the tommyhawking, I was having a hard time getting the boat to fly a hull. That is, until I started
kipping
the boat. Every time the bow went down into the next wave, I would shift my weight forward and then push forward with my forward foot. When I did this, within 2 kips the hull would fly and I would take off like a shot. The first time I did it, I was just screwing around playing with the waves. After getting the same result each time, figured I may be onto something.
I'm used to sailing much heavier boats and have never experienced this before. On the A , I normally try to keep pretty quiet on the wire. But this seemed to work wonders. Am I on to something? Or dreaming this up?
BTW, I think a floater is what I normally flush after talking on the phone.
It didn't feel ill legal
That didn't even cross my mind, seems like that creates a bit of a grey area.
More of a bend the front knee and straighten it at the bottom of the wave. But I see how it could be seen the same way. More shoving it through the trough of the wave than increasing apparent wind I would think. Like I said previously, winds were in a moderate range. I would think that ooching would be used in low wind range to increase apparent.
When I first read the original post, I thought this was an attempt at humor, with the LR and floater comments, etc.
However, since there appears to be a valid point here, keep in mind that RRS 42 can be changed by Class Rules. So, if the sailors in the class determine that some amount of kinetics are an acceptable price to pay to enable more foiling, the class can take the necessary steps to make it legal.
Mike
Several of us steer the boat to some degree with body weight and it makes a difference. For instance:
* pushing the bow down in a lull as you are doing AzCat rather than move the rudder
* stepping aft to help the bow turn up in a puff when going upwind
* standing back in the wire and yanking the mast on top of you to help the boat tack quickly and roll without using as much rudder
* using your back foot in the foot strap to steer the boat when trapezing downwind. This is super effective when foiling and virtually eliminates the need for the rudder.
Most of us weigh as much or more than the boat, so it is really sensitive to body movement and is a lot of fun to play with.
I don't think any of these are illegal if they are done as part of steering but I am not a judge. I have never seen it protested in a number of years of sailing in the class
Class Rules may change RRS 42, although I am not aware of any that do. Sailing instructions may NOT change RRS 42. See RRS 86.1 (a-c).
The Propulsion Basic Rule (RRS 42.1) says (in part),
Her crew may adjust the trim of sails and hull, and perform other acts of seamanship, but shall not otherwise move their bodies to propel the boat
. Moving your body weight to adjust boat balance (weather/lee helm) and thereby steer the boat is an act of seamanship that does not propel the boat and therefore is not prohibited by RRS 42.1.
* pushing the bow down in a lull as you are doing AzCat rather than move the rudder
* stepping aft to help the bow turn up in a puff when going upwind
* using your back foot in the foot strap to steer the boat when trapezing downwind. This is super effective when foiling and virtually eliminates the need for the rudder.
Moving your weight forward or aft to steer without the rudder is allowed - as long as it does not propel the boat.
RRS 42.3
Exceptions
(a) and (b) state
A boat may be rolled to facilitate steering
and
A boat's crew may move their bodies to exaggerate the rolling that facilitates steering the boat through a tack or gybe...
. Therefore, you may pull on the trapeze wire to help roll-tack (or gybe) a boat.
Moving your body to steer is generally ok. Using your body to propel the boat in ANY direction (including keeping it from drifting) is not. How many times have you seen a sailor stick his leg in the water to keep a boat in place on the starting line? Technically, that is illegal.
I've never seen a boat protest another under Rule 42, but I have done on-the-water enforcement (see RRS Appendix P). I've never penalized (nor seen another judge penalize) a boat for anything that wasn't a blatant violation. In my opinion, kinetics don't generally work for catamarans like they do for other boats (such as Lasers), and a lot of things that are technically illegal would never be called even under Appendix P.
I hope that helps,
Eric Rasmussen
US SAILING Certified Judge,
Area D Appeals Committee
Breakin the law is fun!
That didn't even cross my mind, seems like that creates a bit of a grey area.
More of a bend the front knee and straighten it at the bottom of the wave. But I see how it could be seen the same way. More shoving it through the trough of the wave than increasing apparent wind I would think. Like I said previously, winds were in a moderate range. I would think that ooching would be used in low wind range to increase apparent.
I agree with all of your points, Eric. But who suggested changing RRS 42 in SIs?
There are plenty of class rules which change RRS 42. Many dinghy classes and board classes, including Olympic classes do this. Collegiate procedural rules (treated like class rules, which is an interesting work-around) also change RRS 42.
Having said that, I also never said that this should be taken lightly. Careful consideration needs to be made to avoid unintended consequences. There is usually a trial period before committing to an actual change.
The only reason that I brought this up is to make people aware that the rules do allow (limited) flexibility in this regard.
Mike
The feeling I was getting , i.e., the feeling I got through the he boat, was that I was changing the timing of my weights potential kenetic movement , if that makes sense. If I kept my front leg more or less straight and use my back leg as a shock absorber, as the boat hit the trough it would stick the bows and momentarily slow down as the mast move forward and then back again as I climbed the next wave. Instead as I hit the bottom of the trough I kept both knees bent and then straightened my front leg basically changing the timing of when I would feel the boat slow(later) as it as the bow dug into the back of the next wave . Really, a matter of changing the timing and duration of the slowdown through weight placement.
Before I tried this I was reacting to the movement ov the boat.
Instead, I was anticipating the movement of the boat, and using my body weight to help the boat maintain a better average speed, stop tommyhawking(as much) , which increased slightly the apparent wind , more power , flying a hull.
Didn't think I was getting into a
rules
thing. Just adjusting the kenetics of the boat/operator unit.
Again, not reacting to a low wind situation, more the wave state
IMHO, I think the working mechanism behind this
trick
is obvious.
Weight movement induces always a(small)steering effect because of the shifting of the lateral surface.
Moving backward with your body means that you are bearing away (a little).
So what you describe is the common zig-zag course passing through waves as the most efficient way.
In big waves that is a must and you use the tiller for that purpose.
Using your weight in small waves in order to have just that instantaneous tiny effect on the very precise equilibrum of all the concerning forces, is a clever idea.
It therefor has nothing to do with rules.
Yes, that sounds right. With the weight of th Acat, that's very likely what I was doing. And the effect was to smooth out the ride, lessen bow slap/movement , allow the boat to turn slightly without being slowed down by the rudders.
Very dramatic effect on such a lite boat. It really took me by surprise when it happened the first time, and again when it repeated each time I tacked and took off on the new tack.
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