I am preparing for the Small Reach Regatta and want to make sure that I have what the organizers want for flotation. Postings here do not indicate how much added bouyancy is considered enough and the techniques suggested vary from gold plated to what seems inadequate to me. The Coast Guard has no regulation on small sail boats.
Flotation bags sold for whitewater canoes would be a quick and easy way to go. Ads for them on the Internet gave few details. The only one I found with an indication of the material said "light nylon." My thinking is that the heavy PVC/nylon portage bags I already have would be more rugged than that. Their seals may not be absolutely airtight. They seem so, but I would not trust them to hold for an extended time. By filling them with airtight containers (plastic bottles) many air chambers would have to be breached to cause a significant loss of bouyancy. Key to this idea would be in securing the bags in such a way that they would stay in place during an overturning, collision or other "event."
As for the amount of flotation needed I plan to calculate enough to float the ballast, anchor and chain, and other non-floatable items, the weight of the crew plus a safety factor. Ideally the swamped boat should float at or above the top of the centerboard trunk with the crew sitting on the seats but I don't know yet if that is feasable.
So, what do you advise?