Fin keels are the epitome of performance! They project out of the hull as a high aspect ratio appendage with a long leading edge to generate as much lift as possible with as little drag as possible. The narrow fin slices through the water with ease and its airfoil shape adds to its efficiency.
The long fin keel locates the mass of the ballast far from the hull, providing a long lever arm to aid in righting moment. This added leverage uses the ballast more efficiently which means that less ballast is needed. Less ballast also means less weight which directly relates to the yacht having a lighter displacement. Lighter displacement gives the sailboat greater speeds in light airs, and much greater speeds overall. Fin keels truly are the ideal underwater appendage from a performance standpoint!
If your dream yacht is a high performance machine that will zip through the water toward your destination, be sure that you size your keel accordingly to the waters you intend to navigate. The longer the keel, the better the yachts ability to point, but the yacht will also have a deeper draft.
If you plan to cruise in waters that average around 6 feet deep, then a 10 foot keel may be problematic. Your cruising grounds will be severely restricted and limited to only the deeper areas. If you went with a shorter fin keel, you will still have the performance benefits of a fin keel with the increased cruising realm of shallower waters.
It would behave you to look over the charts of your intended navigable waters and examine the charted depths. Identify the creeks and rivers you wish to sail into and record their water depths. By compiling the data by depth, you can see how different drafts will remove potential cruising waters.
Creek A, Creek B, and Creek C have depths of 4 feet;
Creek D, River E, and Bay F have depths 5 feet;
River G, Bay H, and Creek I have depths of 6 feet.
If you choose a boat with a draft less than 4 feet, you could cruise all the bodies of water that you have identified.
If you choose a boat with a draft less than 5 feet, you can no longer enter Creek A, B, or C.
If you choose a boat with a draft less than 6 feel, you can only cruise in River G, Bay H, and Creek I.
If you did not look at your local charts before you purchased your yacht with a 10 foot draft, you would be disappointed when you can not enter any of the cruising waters you wanted to explore!
While fin keels are excellent performers, be sure to size your keel accordingly to the waters you wish to cruise instead of solely focusing on the performance aspects of the keel length.