On Tue, 19 Apr 2005 23:12:12 -0400, Joe Bleau
wrote:

I just finished reading all 57 posts of a msg. which appeared in
February having to do with "whether or not a 45-ft. boat could survive
"severe" weather or something to that effect. I was both informed and
entertained by that thread--informed because there were some excellent
analyses which were enlightening to me and entertained by the quality
of the flames going back and forth.

This might provoke another flame war but I (and others) might learn
something in the process so here goes:

There is a discussion going on in a list-serve group I subscribe to as
to the benefit of adding bouyancy to the top of the mast through an
inflatable device which would automatically deploy were the mast to
become submerged in a roll over. I am fascinated by the concept and
would love to have the input from some of the excellent minds iin this
newsgroup who post on such matters..

Currently there is no such device being marked (but think of the
commericial potential--Waste Marine could make megabucks by having
them manufactured in Taiwan for $25.00 and selling them to their
victims (excuse me--customers) for $2500.00. Some posters suggested
something as simple as running an automatic PFD up to the top of the
mast on a halyard when conditions warranted. Others suggested
canister-type inflatable devices permanently mounted. Some claimed
such a device would cause the mast to break. Others claim the devices
would right the boat forthwith. There are elaborate calculations
"proving" that the 40 or so pounds of bouyancy offered by the PFD
would equal thousands of pounds in righting force.

And . . . for the final word from our panel of experts.

Suppose the boat is on its side. 4000 lbs of lead is centered 6 feet
from the center of buoyancy. 40 lbs of floatation is centered 60 feet
the other way.


I make that 24,000 lb-ft of righting moment from the keel, and 2400
lb-ft from the floatation. The ratio is not going to change much with
the masthead down in the water more.




Rodney Myrvaagnes NYC J36 Gjo/a

"Religious wisdom is to wisdom as military music is to music."