Join Date: Aug 2013
Thanked 19 Times in 19 Posts
Rep Power: 4
Re: To stop pitching, no not horseshoes.
The idea is not as bad as some of you want it to be. Those active in sailing some 3-4 decades ago may remember that about the same theory was quoted when pitching was to heavy during sailing - the cure was said to put something heavy (as a crew member) at the crosstrees in the mast.
And it worked - sometimes.
When pitching heavily there is a resonance, caused by wind, waves and the boat, mainly its moment of inertia. The moment of inertia can be changed be re-distribute weights on the boat, which might move the boat out of resonance with the waves & wind.
To this one should also note that the moment of inertia is proportional to the mass (weight) * r*r where r is the distance between the centre and the centre of the weight (google Steiners theorem if you want to know more). Thus ... distance is more important than weight, the further out the more moment of inertia is changed.
No 1000 pound is needed to make this change on a 40 ft boat. It is often perfectly enough with some few 100 pounds ... conclusion is given, eeh?
Now, all this is nice. In reality sea waves are not of one frequency, but have a wide distribution (a wide normal distribution if anything). In order to really avoid resonance effects, moment of inertia should be changed rather dramatically. So, these few 100 pounds, could they be kind enough to move up to the top of the mast?
OK, if all this works out well, what happens then when wind changes? Oh, new possibilities for resonances!
There are other methods, actually. But weights work, in theory and practice.